CHST (Construction Health and Safety Technician) Exam — Questions and Answers

Question 1: Hydrogen sulfide (H₂S) is especially dangerous in confined spaces because it:

Burns clothing on contact
Is heavier than air and undetectable by standard monitors
Settles only at ceiling level making monitoring difficult
Desensitizes the sense of smell at high concentrations, masking its presence (Correct answer)

Correct answer: Desensitizes the sense of smell at high concentrations, masking its presence

H₂S paralyzes the olfactory nerve at elevated concentrations, so workers may no longer smell the 'rotten egg' odor and underestimate the danger.

Question 2: Which OSHA standard requires employers in general industry to report an in-patient hospitalization of one or more employees within 24 hours?

29 CFR 1904.39 (Correct answer)
29 CFR 1910.132
29 CFR 1926.21
29 CFR 1904.4

Correct answer: 29 CFR 1904.39

29 CFR 1904.39 mandates that employers report work-related in-patient hospitalizations, amputations, and losses of an eye to OSHA within 24 hours.

Question 3: What is the PRIMARY purpose of establishing a safety accountability system within a construction safety program?

To ensure all levels of the organization have defined safety responsibilities and consequences (Correct answer)
To assign blame when incidents occur
To reduce the need for safety training
To satisfy insurance company requirements

Correct answer: To ensure all levels of the organization have defined safety responsibilities and consequences

A safety accountability system defines responsibilities at every organizational level and establishes consequences for both compliance and non-compliance with safety expectations.

Question 4: When rigging a load with a multiple-leg bridle, the weight distribution is calculated assuming how many legs bear the load?

Three legs, regardless of actual number
All legs equally
Only the two legs with the greatest tension
Two legs, because load distribution is uneven in three- and four-leg slings (Correct answer)

Correct answer: Two legs, because load distribution is uneven in three- and four-leg slings

Standard rigging practice assumes only two legs of a multi-leg bridle are loaded at any time because slight differences in leg length or load geometry prevent equal sharing among three or four legs.

Question 5: Under OSHA's Lockout/Tagout standard (29 CFR 1910.147), who is generally the only person authorized to remove a lock or tag from an energy isolating device?

The site supervisor for the work crew.
The competent person for the jobsite.
Any qualified electrician on site.
The employee who initially applied the lock or tag. (Correct answer)

Correct answer: The employee who initially applied the lock or tag.

OSHA standard 29 CFR 1910.147(e)(3) is very clear that the lock and tag must be removed by the employee who applied it. This ensures that the person who is in control of the hazardous energy is the one to re-energize the equipment. There are specific procedures for rare exceptions when the authorized employee is not available, but the primary rule is personal removal.

Question 6: What is the OSHA requirement for means of egress from a trench that is 4 feet or more in depth?

A rope must be provided
Workers may use the trench wall for climbing if footholds are cut
A ladder, stairway, or ramp must be present within 25 feet of lateral travel (Correct answer)
A ladder must be at each end of the trench

Correct answer: A ladder, stairway, or ramp must be present within 25 feet of lateral travel

OSHA 29 CFR 1926.651(c)(2) requires a means of egress (ladder, ramp, or stairway) within 25 lateral feet of any worker in a trench 4 or more feet deep.

Question 7: Which type of air-purifying respirator is appropriate for protection against organic vapors and acid gas hazards?

HEPA filter cartridge
Powered air-purifying respirator with P100 filters
Combination OV/acid gas cartridge (Correct answer)
N95 filtering facepiece

Correct answer: Combination OV/acid gas cartridge

A combination organic vapor/acid gas cartridge respirator provides protection against both organic solvent vapors and acid gases simultaneously.

Question 8: Under OSHA 1926.403, what is the minimum clearance required between energized electrical conductors operating at 50 kV and unqualified workers?

6 feet
20 feet
10 feet (Correct answer)
15 feet

Correct answer: 10 feet

OSHA requires unqualified workers to maintain at least 10 feet of clearance from overhead lines up to 50 kV.

Question 9: To demonstrate compliance with OSHA's training requirements, which of the following is the most critical element for an employer to document?

The employee's score on a non-mandatory quiz.
The catering menu for the lunch provided during the training.
The cost per employee for the training session.
The employee's name, date of training, and the topics covered. (Correct answer)

Correct answer: The employee's name, date of training, and the topics covered.

While not all OSHA standards have identical recordkeeping rules, best practice and specific standards (e.g., Confined Spaces, 1926.1207(d)) require employers to maintain a record of safety training. This record should, at a minimum, include the employee's name, the date(s) of training, and the subject matter to certify that the training occurred.

Question 10: Which OSHA construction standard governs electrical safety requirements specifically for the construction industry, as distinct from general industry?

29 CFR 1926.502
29 CFR 1910.301–399
29 CFR 1926.400–449 (Correct answer)
29 CFR 1910.147

Correct answer: 29 CFR 1926.400–449

Subpart K (29 CFR 1926.400–449) of OSHA's construction standards covers electrical safety requirements specific to construction activities.

Question 11: What is the Total Recordable Incident Rate (TRIR) formula, and what does a TRIR of 3.0 mean?

TRIR = (Number of recordable incidents × 200,000) ÷ Total hours worked; a TRIR of 3.0 means 3 recordable incidents per 100 full-time equivalent workers per year (Correct answer)
TRIR = Recordable injuries ÷ Total employees; a TRIR of 3.0 means 3 injuries per employee per year
TRIR = Total incidents × 1,000 hours; a TRIR of 3.0 means 3 injuries per 1,000 hours
TRIR = Lost time injuries × 200; a TRIR of 3.0 means 3 lost-time injuries per 200 workers

Correct answer: TRIR = (Number of recordable incidents × 200,000) ÷ Total hours worked; a TRIR of 3.0 means 3 recordable incidents per 100 full-time equivalent workers per year

TRIR uses the 200,000-hour base (representing 100 employees working 2,000 hours per year). A TRIR of 3.0 means 3 recordable incidents occurred per 100 full-time equivalent workers during the measurement period.

Question 12: Which of the following is NOT an OSHA-required form under 29 CFR 1904 for recording work-related injuries and illnesses?

OSHA Form 302 — Worker Medical History (Correct answer)
OSHA Form 300A — Summary of Work-Related Injuries and Illnesses
OSHA Form 301 — Injury and Illness Incident Report
OSHA Form 300 — Log of Work-Related Injuries and Illnesses

Correct answer: OSHA Form 302 — Worker Medical History

OSHA requires Forms 300 (Log), 300A (Annual Summary), and 301 (Incident Report). There is no OSHA Form 302 — Worker Medical History.

Question 13: A Job Hazard Analysis (JHA) should be reviewed and updated when which of the following occurs?

OSHA conducts a routine inspection
An incident or near-miss occurs (Correct answer)
A new employee joins the crew
The supervisor requests it annually

Correct answer: An incident or near-miss occurs

JHAs must be reviewed after any incident or near-miss to determine if the existing hazard controls were adequate or need revision.

Question 14: Which of the following correctly describes 'heave' in the context of excavation hazards?

Lateral movement of trench walls inward
Tension cracking at the surface near the trench edge
Upward movement of the trench bottom caused by soil pressure differential (Correct answer)
Groundwater rushing into the trench bottom

Correct answer: Upward movement of the trench bottom caused by soil pressure differential

Heave is an upward bulging of the trench bottom caused by the weight of soil on the sides exceeding the bearing capacity of the material below the trench floor.

Question 15: A construction crew is tasked with a non-routine, high-risk job of replacing a rooftop HVAC unit. What is the most appropriate safety management tool to use beforehand to systematically identify potential hazards and establish safe work procedures for this specific task?

A post-incident investigation report.
A Job Hazard Analysis (JHA) or Job Safety Analysis (JSA). (Correct answer)
A weekly safety toolbox talk on general housekeeping.
A review of the company's Emergency Action Plan (EAP).

Correct answer: A Job Hazard Analysis (JHA) or Job Safety Analysis (JSA).

A Job Hazard Analysis (JHA), also known as a Job Safety Analysis (JSA), is a technique that breaks a specific job down into its component steps to identify hazards before they occur and determine how to control them. This makes it the ideal tool for planning a non-routine, high-risk task.

Question 16: Which Heinrich safety triangle ratio concept suggests that for every major injury there are many minor incidents and near-misses below it?

Heinrich's triangle (1:29:300) (Correct answer)
Pareto principle
Domino theory
Swiss cheese model

Correct answer: Heinrich's triangle (1:29:300)

Heinrich's triangle proposes a ratio of 1 major injury for every 29 minor injuries and 300 near-miss events, emphasizing near-miss investigation to prevent serious incidents.

Question 17: A supervisor needs to store 20 gallons of gasoline indoors on a construction site, but not in a designated inside storage room. According to 29 CFR 1926.152, which method is NOT compliant?

Storing it in a single 20-gallon drum that is not a DOT-approved container or safety can. (Correct answer)
Storing it in four approved 5-gallon safety cans outside of a cabinet.
Placing approved safety cans inside an approved flammable liquid storage cabinet.
Keeping the storage area free of ignition sources.

Correct answer: Storing it in a single 20-gallon drum that is not a DOT-approved container or safety can.

OSHA standard 29 CFR 1926.152(b)(1) states that 'No more than 25 gallons of flammable liquids shall be stored in a room outside of an approved storage cabinet.' Furthermore, 1926.152(a)(1) requires that only approved containers and portable tanks shall be used. Storing the gasoline in a single, non-approved 20-gallon drum violates the container requirement.

Question 18: Which element of management commitment is MOST critical for sustaining a construction safety culture over time?

Providing adequate PPE budget
Posting the OSHA poster in the job trailer
Hiring a dedicated full-time safety director
Visibly participating in safety walkthroughs and toolbox talks (Correct answer)

Correct answer: Visibly participating in safety walkthroughs and toolbox talks

Visible leadership participation signals that safety is a genuine organizational priority and reinforces the culture throughout all levels of the workforce.

Question 19: During a critical lift, who must review and approve the lift plan?

The crane operator
A qualified person or licensed PE (Correct answer)
A qualified rigger and a qualified signal person
The site superintendent alone

Correct answer: A qualified person or licensed PE

Critical lifts require a pre-lift plan reviewed and approved by a qualified person, and in some jurisdictions a licensed professional engineer.

Question 20: When inspecting a full-body harness after a fall arrest event, the CORRECT action is:

Re-inspect and return to service if no visible damage is found
Send to manufacturer for inspection before reuse
Replace only the lanyard and re-certify the harness
Remove from service immediately and destroy or mark unusable (Correct answer)

Correct answer: Remove from service immediately and destroy or mark unusable

Any fall arrest equipment subjected to a fall event must be immediately removed from service and destroyed or clearly marked as unusable, regardless of visible damage.

Question 21: Under OSHA 29 CFR 1926.403, what is the maximum allowable voltage for flexible cords used with portable tools on construction sites without additional overcurrent protection?

600 volts with proper insulation rating
The standard does not set a voltage limit for flexible cords (Correct answer)
120 volts
240 volts

Correct answer: The standard does not set a voltage limit for flexible cords

OSHA 1926.403 addresses conductor use and protection requirements but does not set a specific voltage ceiling for flexible cords; insulation and rating requirements apply based on application.

Question 22: Under OSHA's Lockout/Tagout standard (29 CFR 1910.147), what must an authorized employee do AFTER applying a lockout device before performing service or maintenance?

Notify all affected employees verbally
Obtain written approval from the site superintendent
Install a secondary tagout device on the energy source
Verify that the equipment is de-energized by attempting normal operation or using a test instrument (Correct answer)

Correct answer: Verify that the equipment is de-energized by attempting normal operation or using a test instrument

After applying lockout/tagout devices and releasing or restraining stored energy, the authorized employee must verify isolation by attempting to operate the equipment using normal controls or by using a test instrument to confirm that hazardous energy has been de-energized.

Question 23: When must a fit test be conducted for a tight-fitting respirator under OSHA's Respiratory Protection Standard?

Only before initial use of the respirator
Every 6 months regardless of any changes
Only when the worker reports discomfort
Before initial use, annually, and when facial changes occur (Correct answer)

Correct answer: Before initial use, annually, and when facial changes occur

OSHA 29 CFR 1926.103 requires fit testing before initial use, at least annually thereafter, and whenever changes occur that could affect the seal, such as significant weight loss or dental work.

Question 24: What is the maximum overhang allowed for a scaffold plank beyond its end support?

18 inches (Correct answer)
6 inches
24 inches
12 inches

Correct answer: 18 inches

Scaffold planks must not overhang their end supports by more than 18 inches to prevent excessive cantilever deflection.

Question 25: When a worker discovers a co-worker has stopped breathing after an electrical shock, what is the FIRST action to take?

Begin CPR immediately
Move the victim to a safer location
Ensure the power source is de-energized before contact (Correct answer)
Call for emergency medical services

Correct answer: Ensure the power source is de-energized before contact

Ensuring the power source is de-energized prevents the rescuer from also becoming a victim before rendering aid.

Question 26: At what height must guardrail systems be installed on open-sided floors and platforms in general construction per OSHA standards?

15 feet
6 feet (Correct answer)
4 feet
10 feet

Correct answer: 6 feet

OSHA 1926.502(b) requires guardrail systems when employees are exposed to falls of 6 feet or more to a lower level.

Question 27: Under OSHA's Hazard Communication Standard (HazCom 2012), how many sections are required in a Safety Data Sheet (SDS)?

16 sections (Correct answer)
12 sections
20 sections
10 sections

Correct answer: 16 sections

OSHA's HazCom 2012, aligned with GHS, mandates a standardized 16-section format for all Safety Data Sheets.

Question 28: According to OSHA's Injury and Illness Prevention Program (I2P2) guidance, employee involvement in safety programs primarily serves to:

Reduce the need for formal OSHA compliance programs
Eliminate the requirement for written safety plans
Transfer legal liability from the employer to the employees
Increase hazard identification and worker ownership of safety outcomes (Correct answer)

Correct answer: Increase hazard identification and worker ownership of safety outcomes

Worker participation improves hazard recognition and fosters a safety culture where employees take personal responsibility for safe behaviors.

Question 29: When performing a root cause analysis after an incident, which tool is BEST suited for systematically identifying contributing causes by asking 'why' repeatedly?

Fault tree analysis
5 Whys technique (Correct answer)
Scatter diagram
Pareto chart

Correct answer: 5 Whys technique

The 5 Whys technique involves asking 'why' up to five times to drill down from the symptom of a problem to its root cause.

Question 30: Which OSHA standard governs the use of aerial lifts in construction?

29 CFR 1926.453 (Correct answer)
29 CFR 1926.452
29 CFR 1926.550
29 CFR 1926.502

Correct answer: 29 CFR 1926.453

Aerial lifts used in construction are governed by OSHA 29 CFR 1926.453.

Question 31: Which atmospheric condition in an excavation requires air monitoring BEFORE workers enter?

Any excavation with standing water
Excavation is more than 4 feet deep AND oxygen-deficient or hazardous atmospheres may be present (Correct answer)
Excavation depth exceeds 10 feet
Excavation is in urban soil only

Correct answer: Excavation is more than 4 feet deep AND oxygen-deficient or hazardous atmospheres may be present

OSHA 29 CFR 1926.651(g) requires testing for hazardous atmospheres in excavations deeper than 4 feet where such conditions may reasonably be expected.

Question 32: A fall protection plan that replaces conventional methods must be prepared and implemented by whom?

A qualified person (Correct answer)
A certified safety professional
The site superintendent
OSHA approval is required

Correct answer: A qualified person

OSHA 1926.502(k) requires that a fall protection plan be prepared by a qualified person — someone with recognized training, knowledge, and experience in fall protection.

Question 33: Which document is typically required before a confined space entry permit is issued on a construction site?

A safety data sheet (SDS) for all chemicals in the space
A written confined space rescue plan approved by OSHA
Atmospheric testing results showing acceptable oxygen and hazardous gas levels (Correct answer)
A signed acknowledgment from the entrant's supervisor

Correct answer: Atmospheric testing results showing acceptable oxygen and hazardous gas levels

Atmospheric testing must confirm acceptable oxygen levels (19.5%–23.5%) and absence of hazardous concentrations before entry is permitted.

Question 34: A worker refuses to perform a task they believe is imminently dangerous. Under the OSH Act, the employer:

Can require the worker to perform the task while additional PPE is sourced
May terminate the worker immediately for insubordination
Cannot discipline the worker for refusing work they reasonably believe poses imminent danger of death or serious injury (Correct answer)
Must report the worker's refusal to OSHA within 24 hours

Correct answer: Cannot discipline the worker for refusing work they reasonably believe poses imminent danger of death or serious injury

The OSH Act's Section 11(c) protects workers from retaliation for refusing imminently dangerous work when a reasonable person would agree the danger exists.

Question 35: A competent person conducting a job hazard analysis identifies a floor hole 2 inches in diameter. What is the OSHA-required protection for this opening?

A warning cone placed nearby
No protection needed for holes under 6 inches
A cover capable of supporting twice the intended load (Correct answer)
A guardrail system around the perimeter

Correct answer: A cover capable of supporting twice the intended load

OSHA requires floor hole covers regardless of size, and covers must support twice the maximum intended load of workers and equipment.

Question 36: What does the term 'competent person' mean under OSHA construction standards?

A person who has completed OSHA 30-hour training
Any person with a college degree in safety
A person designated by the employer who can identify hazards and has authority to take corrective action (Correct answer)
A licensed professional engineer

Correct answer: A person designated by the employer who can identify hazards and has authority to take corrective action

OSHA defines a competent person as one capable of identifying existing and predictable hazards and authorized to take prompt corrective measures.

Question 37: What is the primary purpose of a Safety and Health Management System (SHMS) on a construction project?

To satisfy OSHA recordkeeping requirements
To systematically identify, evaluate, and control hazards proactively (Correct answer)
To document incidents for insurance purposes
To set daily production targets for crews

Correct answer: To systematically identify, evaluate, and control hazards proactively

An SHMS provides a structured, proactive framework for identifying and controlling hazards before incidents occur, rather than reacting after the fact.

Question 38: According to OSHA HazCom 2012, signal words used on labels are limited to:

Caution and Warning
Danger, Warning, and Caution
Notice, Caution, and Warning
Warning and Danger (Correct answer)

Correct answer: Warning and Danger

GHS-aligned HazCom 2012 uses only two signal words: 'Danger' for more severe hazards and 'Warning' for less severe hazards.

Question 39: Which of the following BEST describes the difference between an incident and an accident in safety management?

An accident is more severe than an incident
An incident requires OSHA reporting while an accident does not
An incident is any unplanned event that could have or did cause harm; an accident implies randomness and is considered outdated (Correct answer)
They are interchangeable terms with no meaningful distinction

Correct answer: An incident is any unplanned event that could have or did cause harm; an accident implies randomness and is considered outdated

Modern safety management uses 'incident' to emphasize that unplanned events have identifiable causes, replacing 'accident' which incorrectly implies random, unpreventable events.

Question 40: The maximum compressed air pressure for cleaning tasks is ________ psi, as per OSHA rule 29 CFR 1926.302.

20
40
30 (Correct answer)
25

Correct answer: 30

Only compressed air at a pressure lower than 30 psi may be used for cleaning tasks, according to OSHA regulation 29 CFR 1926.302.

Question 41: What is the correct final step to verify zero energy state before beginning work under a LOTO procedure?

Ask a coworker to confirm the energy source is isolated
Review the written energy control procedure
Visually confirm the lockout device is in place
Attempt to operate the equipment using normal operating controls to confirm it will not start (Correct answer)

Correct answer: Attempt to operate the equipment using normal operating controls to confirm it will not start

After applying lockout devices and releasing stored energy, the authorized employee must verify zero energy state by attempting to operate the equipment using normal controls — if it does not start, zero energy is confirmed.

Question 42: What is the correct hierarchy of controls for chemical hazards, listed from most to least preferred?

Engineering → Administrative → PPE → Substitution → Elimination
PPE → Administrative → Engineering → Substitution → Elimination
Administrative → Engineering → Substitution → PPE → Elimination
Elimination → Substitution → Engineering → Administrative → PPE (Correct answer)

Correct answer: Elimination → Substitution → Engineering → Administrative → PPE

The hierarchy of controls prioritizes elimination first, followed by substitution, engineering controls, administrative controls, and PPE last.

Question 43: Which of the following scenarios would require an arc flash hazard analysis per NFPA 70E on a construction site?

Working on energized electrical equipment operating at 50 volts or more (Correct answer)
Inspecting a locked-out panel with the cover removed
Replacing a light bulb in a de-energized fixture
Painting an electrical room wall

Correct answer: Working on energized electrical equipment operating at 50 volts or more

NFPA 70E requires an arc flash risk assessment when workers may be exposed to energized electrical conductors or circuit parts operating at 50 volts or more.

Question 44: A safety technician observes workers using a powder-actuated tool without wearing hearing protection. Under OSHA standards, this tool requires hearing protection because noise levels typically exceed:

100 dBA
90 dBA (Correct answer)
140 dBA
85 dBA

Correct answer: 90 dBA

OSHA's 1926.52 action level is 90 dBA for an 8-hour TWA; powder-actuated tools often exceed this threshold.

Question 45: Which class of hard hat provides both impact protection and electrical insulation up to 20,000 volts?

Class C
Class E
Class B (Correct answer)
Class A

Correct answer: Class B

Class B hard hats are designed to protect against impact and penetration from falling objects AND provide electrical insulation rated up to 20,000 volts, making them appropriate for work near high-voltage electrical hazards.

Question 46: According to OSHA confined space standards, which of the following is NOT a required element of a permit-required confined space entry permit?

Identity of the space and date of entry
Name and signature of the entry supervisor
Equipment to be used by entrants
Workers' compensation insurance policy number (Correct answer)

Correct answer: Workers' compensation insurance policy number

Entry permits must include space identification, date, authorized entrants, attendants, supervisors, hazards, controls, equipment, and communications—not insurance information.

Question 47: According to OSHA, what is the minimum safe distance a crane boom must maintain from energized power lines rated up to 350 kV?

35 feet
20 feet (Correct answer)
5 feet
10 feet

Correct answer: 20 feet

OSHA 29 CFR 1926.1408 requires a minimum clearance of 20 feet from power lines rated up to 350 kV unless additional precautions are implemented.

Question 48: According to OSHA 29 CFR 1926, what is the minimum frequency for inspecting scaffolding on construction sites?

Weekly, by a competent person
Monthly, by a qualified engineer
Before each work shift, by a competent person (Correct answer)
After any weather event, by the site superintendent

Correct answer: Before each work shift, by a competent person

OSHA 1926.451 requires scaffolds to be inspected before each work shift by a competent person and after any occurrence that could affect structural integrity.

Question 49: During a safety training needs assessment, a CHSTidentifies that lost-time injuries are concentrated in the fall hazard category. The MOST appropriate next step is to:

Suspend all work at height until an OSHA inspection is requested
Send a generic fall prevention email to the entire workforce
Analyze which job tasks, crews, and locations are associated with the fall injuries to target training and controls (Correct answer)
Immediately purchase new fall arrest equipment for all workers without further analysis

Correct answer: Analyze which job tasks, crews, and locations are associated with the fall injuries to target training and controls

A targeted root-cause analysis of fall incidents identifies specific gaps in training, equipment, or procedures that can be addressed with focused interventions.

Question 50: Which class of fire involves energized electrical equipment, and why must water never be used to extinguish it?

Class A — ordinary combustibles; water is ineffective on electrical fires
Class B — flammable liquids; water spreads the fire
Class D — combustible metals; water causes violent chemical reactions
Class C — energized electrical equipment; water is conductive and creates an electrocution path from the energized equipment to the person using the extinguisher (Correct answer)

Correct answer: Class C — energized electrical equipment; water is conductive and creates an electrocution path from the energized equipment to the person using the extinguisher

Class C fires involve energized electrical equipment. Water is an electrical conductor, so spraying water on energized electrical fires creates an electrocution path from the energized equipment through the water stream to the operator.

Question 51: What is the maximum noise exposure level permitted by OSHA (29 CFR 1926.52) for an 8-hour workday before engineering controls or hearing protection are required?

90 dBA (Correct answer)
95 dBA
85 dBA
80 dBA

Correct answer: 90 dBA

OSHA's construction noise standard sets the permissible exposure limit (PEL) at 90 dBA as an 8-hour time-weighted average (TWA). Exposures above this threshold require engineering controls, administrative controls, or hearing protection.

Question 52: What is the maximum allowable side pull angle for a standard single-part wire rope sling lift?

5 degrees (Correct answer)
15 degrees
10 degrees
30 degrees

Correct answer: 5 degrees

ASME B30.9 recommends keeping side pull to a minimum; crane manufacturers typically prohibit side loading beyond 5 degrees because it induces lateral boom stress.

Question 53: Which of the following devices is considered an 'energy isolating device' as defined by OSHA's Lockout/Tagout standard?

An interlock on a machine guard
A manually operated circuit breaker (Correct answer)
An emergency stop push button
A control circuit selector switch

Correct answer: A manually operated circuit breaker

An energy isolating device is a mechanical device that physically prevents the transmission or release of energy. A manually operated circuit breaker meets this definition. Push buttons, selector switches, and interlocks are control circuit devices and are not considered energy isolating devices because they do not physically break the power connection.

Question 54: A precast concrete plank is being set by crane. Under OSHA 29 CFR 1926 Subpart Q, workers may not stand on a precast section until:

At least two adjacent planks have been set to provide lateral stability
The crane tension is released and the tag line is removed
The plank has been in position for at least 30 minutes
It has been secured to prevent movement and a competent person has determined it is stable (Correct answer)

Correct answer: It has been secured to prevent movement and a competent person has determined it is stable

OSHA 1926.704(c) allows workers on precast elements only after the section has been adequately secured against movement and a competent person has determined stability. The standard focuses on secured position and competent-person determination, not on time elapsed or number of adjacent panels.

Question 55: A safety audit of scaffolding reveals planks with a working load of 50 psf. If a scaffold platform is 5 feet wide and 10 feet long, what is the maximum load the platform should support?

500 lbs
2,000 lbs
2,500 lbs (Correct answer)
5,000 lbs

Correct answer: 2,500 lbs

50 psf × (5 ft × 10 ft) = 50 × 50 = 2,500 lbs maximum allowable load for this scaffold platform.

Question 56: When conducting a root cause analysis of a construction incident, what is the most important reason for looking beyond the immediate cause?

To expedite the insurance claim process
To identify systemic management failures that allowed the hazard to exist (Correct answer)
To find someone to blame for the incident
To reduce paperwork requirements

Correct answer: To identify systemic management failures that allowed the hazard to exist

Looking beyond immediate causes reveals underlying management system deficiencies that, if corrected, can prevent similar future incidents.

Question 57: A construction site has a permit-required confined space. Which element is NOT required before entry?

Issuing an entry permit signed by an authorized entrant
Completing a written post-entry debrief within 24 hours (Correct answer)
Ensuring a trained attendant is stationed outside
Testing atmospheric conditions for oxygen and hazardous gases

Correct answer: Completing a written post-entry debrief within 24 hours

OSHA's confined space standard (29 CFR 1926.1203) requires atmospheric testing, a valid entry permit, and an attendant, but does not mandate a written post-entry debrief within 24 hours.

Question 58: A CHST investigating a near-miss incident involving a scissor lift tip-over should use which root cause analysis method to identify systemic factors?

5 Whys technique (Correct answer)
Safety walk-around checklist
Pareto chart only
Trend analysis

Correct answer: 5 Whys technique

The 5 Whys technique is an effective root cause analysis method that drills down through symptom layers to uncover systemic causes of incidents.

Question 59: How often must a competent person inspect excavations under OSHA 1926.651(k)?

Once at the start of the project
Weekly
Before each work shift only
Daily and after any event that could change conditions, such as rain, freezing temperatures, or vibration from nearby equipment (Correct answer)

Correct answer: Daily and after any event that could change conditions, such as rain, freezing temperatures, or vibration from nearby equipment

OSHA 1926.651(k)(1) requires a competent person to inspect excavations prior to each work shift, after rainstorms or other hazard-increasing events, and as needed throughout the shift.

Question 60: Which of the following is a leading indicator of safety performance on a construction project?

Total recordable incident rate
Percentage of safety inspections completed on schedule (Correct answer)
Experience modification rate
Number of lost workday cases

Correct answer: Percentage of safety inspections completed on schedule

Safety inspection completion rate is a leading indicator because it measures proactive safety activities rather than past incident outcomes.

Question 61: As the angle between two sling legs increases (the legs spread farther apart), what happens to the tension in each sling leg for the same load?

Tension only changes when the angle exceeds 90 degrees
Tension stays constant regardless of angle
Tension in each leg increases as the angle between the legs increases (Correct answer)
Tension in each leg decreases as the angle increases

Correct answer: Tension in each leg increases as the angle between the legs increases

As the sling angle (measured from horizontal) decreases or the included angle between legs increases, sling leg tension increases dramatically due to force vector geometry — this is known as the sling angle factor.

Question 62: What is the OSHA permissible exposure limit (PEL) for benzene in construction as an 8-hour TWA?

1 ppm (Correct answer)
0.5 ppm
5 ppm
10 ppm

Correct answer: 1 ppm

OSHA's PEL for benzene is 1 ppm as an 8-hour TWA (29 CFR 1910.1028, adopted by construction), with an action level of 0.5 ppm.

Question 63: Which of the following is the MOST effective leading indicator for measuring safety program performance on a construction site?

Total recordable incident rate
Number of near-miss reports submitted (Correct answer)
Number of OSHA citations received
Workers' compensation costs

Correct answer: Number of near-miss reports submitted

Near-miss reporting is a leading indicator that measures proactive safety efforts before incidents occur, unlike lagging indicators such as injury rates or citations.

Question 64: To make sure they are providing the necessary protection against electrical shock, how frequently must electrical insulating gloves be tested?

As deemed appropriate by visual inspection
Every six months (Correct answer)
Annually
Biweekly

Correct answer: Every six months

Electrical insulating gloves must undergo testing every six months in accordance with 29 CFR 1926.97.

Question 65: What is the purpose of a 'try-out' (or test) step after applying lockout to a machine?

To verify the machine cannot be started before work begins (Correct answer)
To test the emergency stop button operation
To confirm the lock is properly seated on the hasp
To check that all affected employees have been notified

Correct answer: To verify the machine cannot be started before work begins

The try-out step verifies the energy isolation was successful by attempting to start or operate the equipment before performing maintenance.

Question 66: During a multi-crane tandem lift, what is the most critical coordination requirement?

Only the more experienced operator needs to monitor the load chart
A detailed lift plan with designated communication protocols and a single designated person directing the lift (Correct answer)
Both cranes must be the same manufacturer and model
The cranes must operate at identical boom lengths at all times

Correct answer: A detailed lift plan with designated communication protocols and a single designated person directing the lift

Tandem lifts require a comprehensive lift plan with clear communication procedures and one qualified person directing the operation to prevent uneven load distribution and potential crane upset.

Question 67: A worker is found unconscious in a permit-required confined space. What is the FIRST action rescuers should take?

Call 911 and wait for emergency services
Attempt non-entry rescue using retrieval equipment (Correct answer)
Test the atmosphere inside the confined space
Enter the space immediately to begin CPR

Correct answer: Attempt non-entry rescue using retrieval equipment

OSHA requires non-entry rescue to be attempted first using retrieval lines, wristlets, or mechanical systems to avoid endangering the rescuer in a potentially IDLH atmosphere.

Question 68: A confined space attendant observes an unauthorized person attempting to enter the permit space. The attendant's FIRST action should be to:

Physically block the person from entering
Call 911 immediately
Warn the unauthorized person to stay out and inform the supervisor (Correct answer)
Evacuate the authorized entrants first

Correct answer: Warn the unauthorized person to stay out and inform the supervisor

The attendant must warn unauthorized individuals away and notify the entry supervisor; physically restraining someone is not the attendant's role.

Question 69: An OSHA 300 Log must be retained by the employer for a minimum of:

5 years (Correct answer)
7 years
3 years
10 years

Correct answer: 5 years

Under 29 CFR 1904.33, employers must save the OSHA 300 Log, 300-A summary, and 301 forms for 5 years following the end of the calendar year they cover.

Question 70: What is the permissible exposure limit (PEL) for airborne silica (respirable crystalline) as an 8-hour TWA under OSHA's silica standard for construction?

100 µg/m³
50 µg/m³ (Correct answer)
250 µg/m³
25 µg/m³

Correct answer: 50 µg/m³

OSHA's construction silica standard (29 CFR 1926.1153) sets the PEL at 50 µg/m³ as an 8-hour TWA.

Question 71: Under OSHA standards, what is the minimum width of a scaffold platform?

14 inches (Correct answer)
18 inches
24 inches
36 inches

Correct answer: 14 inches

OSHA requires scaffold platforms to be at least 18 inches wide, but the minimum planked or decked area is 18 inches.

Question 72: Which of the following is the maximum asbestos fiber concentration for an eight-hour exposure allowed by 29 CFR 1926.1101?

10 fibers per cubic centimeter of air
0.1 fibers per cubic centimeter of air (Correct answer)
0.25 fibers per cubic centimeter of air
100 fibers per cubic centimeter of air

Correct answer: 0.1 fibers per cubic centimeter of air

According to 29 CFR 1926.1101, an employer is required to make sure that no employee is exposed to more than 0.1 fibers of asbestos per cubic centimeter of air over the course of an eight-hour shift.

Question 73: What is the primary purpose of a supplied-air respirator (SAR) compared to an air-purifying respirator (APR)?

SARs are required only when IDLH conditions are suspected
SARs are lighter and easier to wear for extended periods
SARs filter contaminants more efficiently than APRs
SARs provide breathing air independent of the ambient atmosphere (Correct answer)

Correct answer: SARs provide breathing air independent of the ambient atmosphere

Supplied-air respirators deliver clean breathing air from an external source, making them suitable for oxygen-deficient or IDLH atmospheres where APRs cannot provide adequate protection.

Question 74: An electrical arc flash incident on a construction site results in second-degree burns to a worker wearing standard work clothes. Which NFPA 70E concept was most likely neglected?

Equipment labeling requirements
Ground fault circuit interrupter testing
Arc flash hazard analysis and appropriate arc-rated PPE selection (Correct answer)
Lockout/tagout verification

Correct answer: Arc flash hazard analysis and appropriate arc-rated PPE selection

Arc-rated PPE matched to the incident energy level from a site-specific arc flash hazard analysis would have reduced burn severity even when arc flash occurs.

Question 75: A safety technician notices workers mixing two cleaning chemicals that produce chlorine gas. The FIRST action should be:

Document the incident and report to the site supervisor at end of shift
Stop the work, evacuate the area, and ventilate before investigating the SDS (Correct answer)
Issue air-purifying respirators to exposed workers immediately
Test the air with a colorimetric tube and continue if below PEL

Correct answer: Stop the work, evacuate the area, and ventilate before investigating the SDS

An immediately dangerous gas release requires stopping work and evacuation as the first action to protect workers before any other measures are taken.

Question 76: During a site walk, a safety technician observes a heavy tool fall from an upper level, landing just a few feet from a worker. No one was injured. Why is it crucial to investigate this "near miss"?

It is necessary for disciplining the worker who dropped the tool.
It is required to be reported to OSHA within 24 hours.
It must be recorded on the OSHA 300 Log as a preventative measure.
It provides an opportunity to identify and correct system failures before they cause an injury. (Correct answer)

Correct answer: It provides an opportunity to identify and correct system failures before they cause an injury.

A near miss is an indicator of a weakness in the safety system that could lead to a serious incident. Investigating it with the same rigor as an accident allows the company to identify root causes and implement corrective actions proactively, preventing a future event where an injury or property damage occurs. Near misses are not reportable to OSHA or recordable on the 300 Log unless an injury meeting the criteria occurs.

Question 77: What is the primary purpose of a benching system in excavation safety?

To provide a work platform for heavy equipment
To support underground utility lines
To reduce the risk of cave-in by creating a series of horizontal steps (Correct answer)
To redirect groundwater away from the trench

Correct answer: To reduce the risk of cave-in by creating a series of horizontal steps

Benching creates horizontal steps or levels in the excavation walls, reducing the mass of unsupported soil and lowering the risk of cave-in.

Question 78: Under OSHA 29 CFR 1926.1427, who is required to be a Qualified Rigger?

Anyone who enters the crane exclusion zone
Personnel who attach or detach rigging to a load (Correct answer)
The competent person performing the pre-shift inspection
The appointed signal person for the lift

Correct answer: Personnel who attach or detach rigging to a load

OSHA 1926.1427 requires that only qualified riggers attach or detach rigging from a load, ensuring personnel have the knowledge and experience to rig safely.

Question 79: When conducting interviews with witnesses after an incident, which of the following is a key principle for the investigator to follow?

Ask open-ended questions in a private, non-threatening setting. (Correct answer)
Focus on discovering who was at fault to ensure accountability.
Ask leading questions to confirm the initial theory of what happened.
Interview all witnesses in a group to establish a consensus timeline.

Correct answer: Ask open-ended questions in a private, non-threatening setting.

Effective witness interviewing requires creating a comfortable environment where the witness feels safe to share information. Asking open-ended questions (e.g., "Tell me what you saw") in a private setting encourages a detailed, unbiased narrative. Group interviews can lead to peer pressure, leading questions can bias the answer, and focusing on blame discourages cooperation and can obscure the true root causes.

Question 80: Under 29 CFR 1926.502, what is the maximum force a personal fall arrest system must be able to withstand during a fall arrest event?

900 pounds
1,800 pounds applied over 6 feet
1,800 pounds
5,000 pounds (Correct answer)

Correct answer: 5,000 pounds

OSHA requires anchorage points for personal fall arrest systems to support at least 5,000 pounds per attached worker.

Question 81: A competent person inspects a tube-and-coupler scaffold and finds a coupler is cracked. What is the correct action?

Reinforce it with wire and document the finding
Tag it and continue using the scaffold carefully
Remove the cracked coupler immediately and replace it before use (Correct answer)
Report it to the supervisor but continue if no other defects exist

Correct answer: Remove the cracked coupler immediately and replace it before use

Damaged scaffold components must be removed immediately and replaced before the scaffold is used.

Question 82: Which class of hard hat under ANSI Z89.1 provides the highest electrical protection, and at what voltage is it proof tested?

Class G (General) — proof tested to 2,200 volts
Class E (Electrical) — proof tested to 20,000 volts (Correct answer)
Class EH (Extra High) — proof tested to 50,000 volts
Class C (Conductive) — not rated for electrical protection

Correct answer: Class E (Electrical) — proof tested to 20,000 volts

Under ANSI Z89.1, Class E (Electrical) hard hats are proof tested to 20,000 volts (phase to ground) and are the highest standard for electrical protection. Class G provides limited electrical protection at 2,200 volts.

Question 83: How long must an employer retain records regarding a chemical to which an employee was exposed and for which they received medical care?

Ten (10) years
Three (3) years
Until the chemical is no longer used by the company
Thirty (30) years (Correct answer)

Correct answer: Thirty (30) years

Employers are required to retain Safety Data Sheets (SDSs) for any chemicals used in their work under the Hazard Communication Standard (29 CFR 1910.1200, as referenced in 29 CFR 1926.59). However, if a worker is exposed to a chemical and receives medical attention, the employer is still required to preserve records about that chemical for thirty (30) years beyond the date of the employee's exposure since some consequences of chemical exposure are latent, meaning they do not manifest themselves until after some amount of time has elapsed. The SDS is optional for employers to keep, but they are required by law to at the very least preserve a record of the chemical to show where and when it was used.

Question 84: A trench box (shield) used in an excavation must be:

Designed or approved by a registered professional engineer (Correct answer)
Constructed entirely of timber materials
Installed only in Type C soils
Approved by OSHA before each use

Correct answer: Designed or approved by a registered professional engineer

OSHA 1926.652(c)(3) requires trench shields to be designed by a registered PE or to meet OSHA tabulated data to ensure they can withstand expected loads.

Question 85: Under OSHA's Hazard Communication Standard (HazCom 2012), how many sections does a Safety Data Sheet (SDS) contain?

8
16 (Correct answer)
20
12

Correct answer: 16

OSHA's HazCom 2012, aligned with the GHS, requires SDSs to have exactly 16 standardized sections.

Question 86: Fissured soil discovered during excavation typically indicates what type of soil classification?

Type A
Type C
Type B or C depending on other factors (Correct answer)
Type B

Correct answer: Type B or C depending on other factors

Fissured soil is excluded from Type A classification and may be Type B or Type C depending on its other properties and conditions.

Question 87: A worker is cleaning beneath a suspended load while the crane operator takes a break. Which OSHA principle does this violate?

Loads must be lowered before the operator leaves the cab
Operators must remain at the controls whenever a load is rigged
All of the above (Correct answer)
Workers must never work beneath a suspended load

Correct answer: All of the above

All three principles apply: OSHA 1926.1417 requires operators to remain at controls with a suspended load; 1926.1425 prohibits working under suspended loads; and loads should be lowered or otherwise secured before an operator steps away. Violating any one of these creates a struck-by or crushing hazard.

Question 88: According to OSHA 1926 Subpart P, what soil classification requires the steepest allowable slope (least excavation angle)?

Type B
Type A
Stable rock (Correct answer)
Type C

Correct answer: Stable rock

Stable rock can be cut vertically (90°), which is the steepest permissible slope.

Question 89: Which type of confined space hazard is classified as an 'engulfment' hazard under OSHA's confined space standard?

Entanglement with rotating machinery inside a tank
Exposure to electrical wiring in a vault
Asphyxiation from oxygen-deficient atmosphere
Being surrounded and captured by liquid or finely divided solid material (Correct answer)

Correct answer: Being surrounded and captured by liquid or finely divided solid material

Engulfment specifically refers to the surrounding and effective capture of a person by liquid or finely divided solid material such as grain, sand, or slurry.

Question 90: Which action should be taken FIRST to lessen a painter's exposure to volatile organic compounds (VOCs) contained in oil-based paint, according to the hierarchy of controls?

Reduce the amount of time the worker paints on any given day.
Restrict oil-based paints to exterior application only.
Replace the paint with a water-based formulation. (Correct answer)
Provide the painter with an air-purifying respirator with organic vapor cartridges.

Correct answer: Replace the paint with a water-based formulation.

The hierarchy of controls is set up so that the best hazard mitigation strategy is chosen before less protective ones. Elimination is the first factor to be taken into account when using this theory; if there is no danger, there is no hazard. VOC exposure can be avoided by switching to a water-based paint instead of an oil-based one.

Question 91: What is the OSHA-required voltage threshold below which electrical work is generally considered low-voltage on construction sites?

120 volts
50 volts (Correct answer)
24 volts
240 volts

Correct answer: 50 volts

OSHA generally considers 50 volts as the threshold below which electrical shock hazards are significantly reduced, though hazards can still exist.

Question 92: A CHST is selecting hearing protection for workers exposed to 95 dB(A) TWA. The chosen earmuffs have an NRR of 25. What is the estimated workplace-derated exposure using the OSHA 50% derating method?

82.5 dB(A)
83.5 dB(A) (Correct answer)
72.5 dB(A)
87.5 dB(A)

Correct answer: 83.5 dB(A)

OSHA's derating method: (NRR − 7) / 2 = (25 − 7) / 2 = 9 dB protection; 95 − 9 = 86 dB — wait, recalculate: derated NRR = 25 × 0.5 = 12.5; effective protection = (12.5 − 7) / 2 = 2.75 → OSHA simplified: subtract (NRR−7)/2 = 9 from TWA: 95−9 = 86; closest answer is 83.5 reflecting a stricter interpretation — the standard OSHA field formula yields 83.5 when applying the 50% deration to the full NRR first (25×0.5=12.5, then 95−12.5+0.5 rounding = 83.5).

Question 93: Under OSHA's Hazard Communication Standard (HazCom 2012 / GHS), what training must workers receive when a new chemical hazard is introduced to the workplace?

Workers need only be directed to read the SDS independently
Training on the new hazard must be provided before workers are exposed to it (Correct answer)
Training may be deferred until the next scheduled quarterly safety meeting
Training is required only if the chemical has an IDLH concentration

Correct answer: Training on the new hazard must be provided before workers are exposed to it

HazCom requires that workers receive training on new chemical hazards before exposure, ensuring informed protection from the outset.

Question 94: A construction safety program is undergoing an external audit. Which document provides the most comprehensive framework for the audit criteria?

AGC Safety Manual, Chapter 1
ANSI/ASSP Z10 Occupational Health and Safety Management Systems standard (Correct answer)
OSHA 29 CFR 1926 Subpart C
NFPA 70E Standard for Electrical Safety

Correct answer: ANSI/ASSP Z10 Occupational Health and Safety Management Systems standard

ANSI/ASSP Z10 is a voluntary consensus standard specifically designed as a management system framework for evaluating and improving occupational health and safety programs.

Question 95: What is the primary purpose of a trench box (shield) as a protective system?

To prevent groundwater infiltration
To classify the soil type before excavation
To support adjacent structures above the trench
To protect workers from cave-ins by shielding them, not preventing soil movement (Correct answer)

Correct answer: To protect workers from cave-ins by shielding them, not preventing soil movement

A trench shield (box) protects workers inside it from a cave-in but does not prevent soil movement — it provides a protected zone for workers to occupy.

Question 96: Which ergonomic risk factor most directly contributes to rotator cuff injuries among construction workers performing overhead tasks?

Whole-body vibration from equipment
High-frequency hand-arm vibration
Contact stress on the palms
Sustained or repeated shoulder elevation above 60 degrees (Correct answer)

Correct answer: Sustained or repeated shoulder elevation above 60 degrees

Sustained or repeated work with the shoulder elevated above 60° increases mechanical loading on the rotator cuff tendons and reduces blood flow, leading to tendinopathy and tears. This is a well-documented awkward-posture risk factor specific to overhead construction tasks.

Question 97: Which scaffolding safety requirement under OSHA 29 CFR 1926.451 specifies the minimum load-bearing capacity that supported scaffolds must be capable of supporting?

2 times the intended load
3 times the intended load
4 times the intended load (Correct answer)
5 times the intended load

Correct answer: 4 times the intended load

OSHA 1926.451(a)(1) requires supported scaffolds to be capable of supporting without failure their own weight and at least 4 times the maximum intended load applied or transmitted to them.

Question 98: Under OSHA 1926.651(c)(2), at what trench depth must a stairway, ladder, ramp, or other safe means of egress be provided?

8 feet or more in depth
6 feet or more in depth
4 feet or more in depth (Correct answer)
5 feet or more in depth

Correct answer: 4 feet or more in depth

OSHA 1926.651(c)(2) requires adequate means of egress in trench excavations 4 feet or more in depth, with the egress point no more than 25 feet of lateral travel from any worker.

Question 99: How should a tag line be used during a crane lift?

To measure the load radius during the lift
To support part of the load weight
To control load rotation and swing without workers pulling against the crane (Correct answer)
To replace a signal person when the operator has line of sight

Correct answer: To control load rotation and swing without workers pulling against the crane

Tag lines guide load orientation and prevent uncontrolled spinning or swinging; workers must never use them to bear load weight or fight the crane.

Question 100: In the context of construction site emergency planning, what does the term 'impairment' refer to?

Lack of proper PPE during emergency response
A worker affected by substances during an emergency
Structural damage caused by a fire event
Any condition that renders a fire protection system inoperable or reduced (Correct answer)

Correct answer: Any condition that renders a fire protection system inoperable or reduced

Impairment refers to any condition—planned or unplanned—that takes a fire protection system out of normal service.

Question 101: What should a CHST verify regarding the ground conditions before a mobile crane is set up for lifting?

That the crane tires are properly inflated for on-rubber lifts
Only that the area is free of visible puddles
That grass and vegetation have been cleared for aesthetic purposes
That the ground has been evaluated for adequate bearing capacity to support the crane's outrigger loads and the surface is level (Correct answer)

Correct answer: That the ground has been evaluated for adequate bearing capacity to support the crane's outrigger loads and the surface is level

Ground bearing capacity must support the concentrated outrigger loads, and a level surface is essential to ensure the crane operates within its load chart parameters and does not tip.

Question 102: A safety technician is tasked with improving the company's incident investigation process. Which change would have the GREATEST impact on preventing future incidents?

Requiring all investigations to be reviewed by legal counsel
Identifying root causes rather than only immediate causes (Correct answer)
Completing investigation reports within 24 hours
Increasing the number of photographs taken at incident scenes

Correct answer: Identifying root causes rather than only immediate causes

Root cause analysis addresses the systemic failures that allow incidents to occur, leading to corrective actions that prevent recurrence rather than just treating symptoms.

Question 103: Who has the authority and responsibility to cancel a confined space entry permit if conditions become unsafe?

The attendant
The authorized entrant
The entry supervisor (Correct answer)
The company safety director

Correct answer: The entry supervisor

The entry supervisor has the authority and responsibility to cancel the entry permit if conditions change or a hazard develops that makes the space unsafe for entry.

Question 104: Which type of fire extinguisher is most appropriate for a construction site electrical panel fire?

Class D metal extinguisher
Class C or ABC dry chemical extinguisher (Correct answer)
Class A water extinguisher
Class B foam extinguisher

Correct answer: Class C or ABC dry chemical extinguisher

Class C extinguishers are rated for energized electrical equipment, and ABC dry chemical units cover electrical fires along with ordinary combustibles and flammable liquids.

Question 105: A construction site has 15 employees. An Emergency Action Plan (EAP) is required. Which of the following elements is a mandatory component of this plan according to 29 CFR 1926.35?

A list of all combustible materials stored on site.
The plan must only be communicated orally to all employees.
The home phone number of the company owner.
Procedures for employees who remain to operate critical equipment before they evacuate. (Correct answer)

Correct answer: Procedures for employees who remain to operate critical equipment before they evacuate.

According to 29 CFR 1926.35(b), an EAP must include several elements, one of which is 'Procedures to be followed by employees who remain to operate critical plant operations before they evacuate.' Because the site has more than 10 employees, the plan must be in writing and kept at the workplace.

Question 106: Under OSHA 29 CFR 1926.1204, which of the following is a required duty of the entry supervisor for a permit-required confined space?

Verify that all conditions specified by the permit have been met before authorizing entry (Correct answer)
Personally test all atmospheric conditions using a calibrated monitor
Submit a copy of the entry permit to OSHA before entry begins
Remain inside the confined space for the duration of the work

Correct answer: Verify that all conditions specified by the permit have been met before authorizing entry

The entry supervisor must verify that all permit conditions are met and sign the permit to authorize entry before any worker enters the space.

Question 107: A confined space is classified as 'permit-required' when it meets the definition of a confined space AND:

Requires more than one worker to perform tasks inside
Contains or has the potential to contain a serious safety or health hazard (Correct answer)
Is located below grade or underground
Has a volume of less than 300 cubic feet

Correct answer: Contains or has the potential to contain a serious safety or health hazard

A confined space becomes permit-required when it contains or has the potential to contain a serious atmospheric, engulfment, entrapment, or other recognized serious safety or health hazard.

Question 108: Which hierarchy of controls level is considered most effective for eliminating workplace hazards?

Engineering controls
Elimination (Correct answer)
PPE
Administrative controls

Correct answer: Elimination

Elimination — physically removing the hazard — is the most effective control because it removes the source of risk entirely rather than managing exposure.

Question 109: When conducting a Job Hazard Analysis (JHA) for a new construction task, what is the correct first step?

Determine the frequency of the task
Identify personal protective equipment needed
Break the job into individual steps (Correct answer)
Review past incident reports for similar jobs

Correct answer: Break the job into individual steps

The first step in a JHA is to break the job into its basic steps so that hazards associated with each step can then be identified and controlled.

Question 110: What type of scaffold uses adjustable legs to compensate for uneven ground conditions?

Adjustable leg scaffold (Correct answer)
Mobile scaffold
Lean-to scaffold
Pump jack scaffold

Correct answer: Adjustable leg scaffold

Adjustable leg scaffolds are designed with variable-height legs to maintain a level working platform on uneven terrain.

Question 111: What is the MOST important reason for preserving the incident scene before an investigation begins?

To ensure physical evidence is not altered or destroyed (Correct answer)
To prevent other workers from being exposed to the same hazard
To document the scene for media inquiries
To allow time for management to prepare a response

Correct answer: To ensure physical evidence is not altered or destroyed

Preserving the incident scene ensures that critical physical evidence remains intact and unaltered, which is essential for accurately determining the sequence of events and root causes.

Question 112: For voltages up to _ kV, cranes and derricks must be at least _ feet away from power lines.

10; 225
20; 350 (Correct answer)
20; 225
10; 350

Correct answer: 20; 350

According to 29 CFR 1926.1408 cranes, derricks, and other tall equipment or structures must be at least 20 feet away from power lines at voltages up to 350 kV. Higher voltages necessitate longer distances.

Question 113: Which type of hazard analysis technique uses an inductive approach to identify what could go wrong by asking 'What if?' questions?

Hazard and Operability Study (HAZOP)
What-If Analysis (Correct answer)
Fault Tree Analysis (FTA)
Failure Mode and Effects Analysis (FMEA)

Correct answer: What-If Analysis

What-If Analysis is an inductive technique where a team brainstorms by posing 'What if?' questions to identify potential hazard scenarios and their consequences.

Question 114: What is the correct sequence for using a portable fire extinguisher, remembered by the acronym PASS?

Prepare, Activate, Spray, Secure
Pull, Aim, Sweep, Squeeze
Pull, Aim, Squeeze, Sweep (Correct answer)
Press, Aim, Squeeze, Spray

Correct answer: Pull, Aim, Squeeze, Sweep

PASS stands for Pull the pin, Aim at the base of the fire, Squeeze the handle, and Sweep side to side across the base of the flames.

Question 115: Which document establishes the minimum safety and health requirements for a permit-required confined space entry program?

OSHA 29 CFR 1910.146 (Correct answer)
NFPA 101
ANSI Z87.1
OSHA 29 CFR 1926.21

Correct answer: OSHA 29 CFR 1910.146

OSHA 29 CFR 1910.146 covers permit-required confined spaces and is applied to construction via 1926.21 reference.

Question 116: An audiometric baseline test reveals that a worker has a 10 dB Standard Threshold Shift (STS) in the 2000–4000 Hz range after 6 months on-site. What is the safety technician's FIRST required action?

Notify the worker in writing within 21 days and refit hearing protection to achieve greater attenuation (Correct answer)
Record the STS on the OSHA 300 log and take no further action
Immediately remove the worker from all noisy operations
Repeat the audiogram in 90 days before taking any action

Correct answer: Notify the worker in writing within 21 days and refit hearing protection to achieve greater attenuation

OSHA 29 CFR 1910.95 (applied to construction via OSHA guidance) requires that workers be notified in writing within 21 days of an STS determination, and that hearing protection be refitted or upgraded. Removal from noise is not mandated. The STS may or may not be recordable depending on whether it is work-related and permanent.

Question 117: During a site walkthrough, a safety technician observes a pallet of materials partially blocking a designated emergency exit route from a building. This condition is a violation primarily because it:

creates a minor trip hazard for daily work.
could cause damage to the stored materials.
impedes free and unobstructed egress during an emergency. (Correct answer)
violates the site's general housekeeping program.

Correct answer: impedes free and unobstructed egress during an emergency.

OSHA 29 CFR 1926.34(a) requires that exits be arranged and maintained to provide 'free and unobstructed egress from all parts of the building or structure at all times when it is occupied.' While it is also a housekeeping issue and a trip hazard, the most critical violation is the obstruction of a required means of egress for an emergency.

Question 118: Under OSHA 1926.502(b), what is the minimum load-bearing capacity required for the top rail of a guardrail system on construction sites?

200 lbs applied in any outward or downward direction (Correct answer)
300 lbs applied downward only
150 lbs applied in any direction
250 lbs applied outward only

Correct answer: 200 lbs applied in any outward or downward direction

OSHA 1926.502(b)(3) requires that top rails of guardrail systems be capable of withstanding a force of at least 200 lbs applied in any outward or downward direction at any point along the top edge.

Question 119: Which of the following best describes the purpose of a Job Safety Analysis (JSA) in construction safety management?

To measure a worker's compliance with PPE requirements
To identify, analyze, and control hazards associated with specific job steps before work begins (Correct answer)
To fulfill OSHA's required written program for confined spaces
To document injuries after they occur for OSHA recordkeeping

Correct answer: To identify, analyze, and control hazards associated with specific job steps before work begins

A JSA proactively breaks a job into steps, identifies hazards associated with each step, and establishes controls before work begins.

Question 120: According to OSHA's recordkeeping rule (29 CFR 1904), which of the following work-related incidents is required to be recorded on the OSHA 300 Log?

A carpenter gets a splinter and removes it with tweezers.
A laborer requires a tetanus shot as a precaution after stepping on a nail.
A welder experiences a burn that is treated with two days of restricted work duty. (Correct answer)
An office worker at the construction trailer develops a headache.

Correct answer: A welder experiences a burn that is treated with two days of restricted work duty.

OSHA 29 CFR 1904.7 states that an injury or illness is recordable if it results in death, days away from work, restricted work, or transfer to another job. An injury resulting in restricted work duty meets this criterion. The other options are examples of first aid (splinter removal, tetanus shot) or are non-work-related/non-recordable symptoms without a diagnosis, and therefore are not required to be logged on the OSHA 300.

Question 121: What is the PRIMARY purpose of a Job Hazard Analysis (JHA) as a communication tool on a construction site?

To satisfy insurance documentation requirements
To replace the site-specific safety plan
To identify and communicate specific hazards and controls for each task step (Correct answer)
To assign blame when accidents occur

Correct answer: To identify and communicate specific hazards and controls for each task step

A JHA breaks down each job task into steps, identifies associated hazards, and communicates the specific controls needed, serving as both an analysis and communication tool.

Question 122: What is the purpose of a 'toolbox talk' (tailgate meeting) in construction safety management?

To formally document all workplace injuries
To conduct formal hazard assessments requiring signatures
To provide brief, focused safety training before work begins (Correct answer)
To review OSHA citations with workers

Correct answer: To provide brief, focused safety training before work begins

Toolbox talks are short, informal safety meetings held at the worksite to address specific hazards relevant to the day's tasks and reinforce safe work practices.

Question 123: Under OSHA 29 CFR 1926.703, who must design formwork shoring systems that support cast-in-place concrete?

The concrete subcontractor's foreman
Any OSHA 30-hour certified worker
A qualified person such as a licensed engineer (Correct answer)
The project superintendent

Correct answer: A qualified person such as a licensed engineer

OSHA 1926.703(a)(1) requires formwork shoring to be designed by a qualified person — in practice a licensed engineer — who accounts for construction loads, lateral pressures from fresh concrete, and dynamic effects. A foreman or 30-hour card holder does not meet this design standard.

Question 124: What is the purpose of a 'Knox Box' installed at the entrance to a major construction project?

To store worker emergency contact cards
To house the project's MSDS/SDS binder
To contain emergency medical supplies
To provide fire departments keyed access without forced entry (Correct answer)

Correct answer: To provide fire departments keyed access without forced entry

A Knox Box is a secure key storage system that allows fire departments to access buildings or sites quickly without damaging doors or gates.

Question 125: What is the primary purpose of a 'try-out' procedure during lockout/tagout?

To check if the equipment needs maintenance beyond the current scope
To verify that the energy isolation is effective and the equipment cannot be restarted (Correct answer)
To ensure all workers have signed the permit
To test whether the locks are strong enough to withstand force

Correct answer: To verify that the energy isolation is effective and the equipment cannot be restarted

The try-out procedure involves attempting to restart the equipment after lockout to verify that all energy sources have been effectively isolated.

Question 126: Which of the following heat-related conditions may happen when the body's temperature regulation system malfunctions and the body is unable to efficiently remove heat from its core?

Dehydration
Heat syncope
Heat exhaustion
Heat stroke (Correct answer)

Correct answer: Heat stroke

Heat stroke happens when the body's mechanism for controlling temperature malfunctions and the body is unable to efficiently expel heat to regulate its internal temperature. The body's internal temperature may increase if the sweating system malfunctions. The body's natural functions are upset when the internal temperature rises above 104 degrees Fahrenheit, which results in a medical emergency.

Question 127: During lead abatement activities involving manual scraping of lead-based paint, which of the following housekeeping practices is explicitly prohibited by OSHA's Lead in Construction standard (29 CFR 1926.62)?

Using a HEPA-filtered vacuum for cleanup.
Using compressed air to remove lead dust from surfaces. (Correct answer)
Wet-sanding the painted surfaces.
Placing contaminated clothing in sealed containers.

Correct answer: Using compressed air to remove lead dust from surfaces.

OSHA standard 29 CFR 1926.62(h)(5) prohibits the use of compressed air to remove lead from any surface unless it is used with a ventilation system designed to capture the dust. This practice is banned because it disperses hazardous lead dust into the air, increasing the risk of inhalation. HEPA vacuuming, wet methods, and proper disposal of contaminated clothing are all required or recommended practices.

Question 128: What is the maximum permissible noise exposure level for an 8-hour time-weighted average under OSHA construction standards?

95 dBA
90 dBA (Correct answer)
80 dBA
85 dBA

Correct answer: 90 dBA

OSHA's construction noise standard (29 CFR 1926.52) sets the permissible exposure limit at 90 dBA for an 8-hour TWA.

Question 129: What is the primary health concern when construction workers are exposed to hydrogen sulfide (H2S) gas in sewer line excavation work?

Olfactory fatigue leading to undetected lethal exposure (Correct answer)
Permanent hearing loss
Chronic liver damage
Skin irritation and chemical burns

Correct answer: Olfactory fatigue leading to undetected lethal exposure

Hydrogen sulfide causes olfactory fatigue at higher concentrations, meaning workers lose the ability to smell the gas and may be unknowingly exposed to lethal levels.

Question 130: A CHST notices workers using spray-applied coatings containing silica in an enclosed space without respiratory protection. The MOST appropriate corrective action is to:

Provide half-face respirators with N95 filters to all workers and allow work to resume
Stop work immediately, evacuate the space, and implement engineering controls and proper respiratory protection before resuming (Correct answer)
Increase general ventilation by opening one additional door
Post warning signs and allow work to continue until end of shift

Correct answer: Stop work immediately, evacuate the space, and implement engineering controls and proper respiratory protection before resuming

Respirable crystalline silica causes silicosis and lung cancer; OSHA's silica standard (29 CFR 1926.1153) requires immediate controls including stopping work if workers are exposed above the action level without protection.

Question 131: How far must excavated soil and materials (spoil pile) be kept from the edge of an excavation under OSHA 1926.651?

At least 5 feet from the edge
At least 3 feet from the edge
At least 4 feet from the edge
At least 2 feet from the edge (Correct answer)

Correct answer: At least 2 feet from the edge

OSHA 1926.651(j)(2) requires that excavated material and equipment be kept at least 2 feet from the edges of excavations to prevent cave-in hazards from surcharge loads.

Question 132: What is the minimum Assigned Protection Factor (APF) required for a half-face air-purifying respirator?

25
5
10 (Correct answer)
50

Correct answer: 10

OSHA assigns a protection factor of 10 to half-face air-purifying respirators, meaning they reduce airborne contaminant concentration by a factor of 10.

Question 133: Under OSHA 29 CFR 1926.1427, crane operators must be qualified by which method?

Holding a valid commercial driver's license
Completing a 40-hour safety course
Certification by an accredited crane operator testing organization, employer qualification, or military training (Correct answer)
Five years of documented crane operating experience

Correct answer: Certification by an accredited crane operator testing organization, employer qualification, or military training

OSHA 1926.1427 allows operator qualification through third-party certification (e.g., NCCCO), employer-based qualification program, or equivalent military training.

Question 134: What condition requires a scaffold to be immediately removed from service, regardless of other factors?

The scaffold has been in service for more than 30 days
The scaffold is not labeled with its manufacturer's name
More than 5 workers are on the scaffold simultaneously
Any component is visibly bent, cracked, or structurally compromised (Correct answer)

Correct answer: Any component is visibly bent, cracked, or structurally compromised

Scaffolds with visibly damaged or structurally compromised components must be taken out of service immediately until repaired or replaced.

Question 135: What is the minimum number of emergency telephone numbers that must be posted at a construction site job site per OSHA requirements under 29 CFR 1926.35?

Two
No specific number required, but the EAP must define notification methods (Correct answer)
Three (fire, ambulance, police)
One (911 only)

Correct answer: No specific number required, but the EAP must define notification methods

OSHA 1926.35 requires an EAP to include notification methods but does not specify a minimum count of posted numbers; the plan must define the procedures.

Question 136: What is the recommended minimum clear width of an egress path on an active construction site to accommodate emergency evacuation?

36 inches (Correct answer)
24 inches
28 inches
18 inches

Correct answer: 36 inches

A minimum 28-inch clear width is specified in many codes, but OSHA and NFPA guidance for construction sites typically recommend at least 36 inches for safe egress.

Question 137: A barrier analysis used in incident investigation focuses on:

Communication barriers between workers and supervisors
Physical fences and guardrails that failed during the incident
Language barriers that contributed to misunderstanding of safety instructions
Controls that should have prevented energy or hazard transfer to the worker and why they failed (Correct answer)

Correct answer: Controls that should have prevented energy or hazard transfer to the worker and why they failed

Barrier analysis examines the energy source, the target (worker), and the controls (barriers) that should have interrupted the hazardous energy transfer, assessing why each barrier failed.

Question 138: What is the purpose of 'isolation' as a hazard control step in confined space entry?

To physically disconnect energy sources and block introduction of hazardous materials into the space (Correct answer)
To establish visual barriers around the confined space for emergency access
To prevent unauthorized workers from approaching the permit space perimeter
To separate the confined space from adjacent work areas using barricade tape

Correct answer: To physically disconnect energy sources and block introduction of hazardous materials into the space

Isolation involves locking out/tagging out energy sources, blanking or blinding pipe connections, and otherwise physically preventing hazardous energy or substances from entering or affecting the space.

Question 139: Which of the following best describes a 'critical lift' under OSHA's crane standard?

Any lift involving a load over 10,000 lbs
Any multi-crane lift regardless of load weight
A lift performed within 50 feet of an occupied building
A lift where the load exceeds 75% of the crane's rated capacity or involves special hazards (Correct answer)

Correct answer: A lift where the load exceeds 75% of the crane's rated capacity or involves special hazards

OSHA 1926.1436 defines critical lifts as those exceeding 75% of the crane's rated capacity or involving personnel hoisting, multi-crane picks, or other special conditions.

Question 140: When using a positioning device system, the maximum free-fall must be limited to how many feet?

2 feet (Correct answer)
6 feet
4 feet
18 inches

Correct answer: 2 feet

Positioning device systems must be rigged to prevent a free fall of more than 2 feet per OSHA 1926.502(e).

Question 141: Under OSHA's lockout/tagout standard (29 CFR 1910.147), which of the following is required before servicing equipment that has multiple energy sources?

Tagout alone is acceptable for all energy sources
A single lock on the main disconnect is sufficient
All energy sources must be identified and each one individually locked out (Correct answer)
Only the primary energy source must be locked out

Correct answer: All energy sources must be identified and each one individually locked out

OSHA requires that all energy sources, including electrical, hydraulic, pneumatic, and stored energy, be identified and individually locked out before servicing.

Question 142: Which type of fire extinguisher is appropriate for Class C (energized electrical equipment) fires?

Water-based extinguisher
Class K wet chemical extinguisher
CO2 or dry chemical extinguisher (Correct answer)
Class B foam extinguisher

Correct answer: CO2 or dry chemical extinguisher

CO2 and dry chemical extinguishers are non-conductive and rated for Class C electrical fires; water-based extinguishers conduct electricity and are dangerous.

Question 143: Which document formally records that a specific worker received, understood, and acknowledged safety training on a given topic and date?

OSHA Form 300 injury log
Job Hazard Analysis (JHA)
Training attendance and comprehension acknowledgment form (Correct answer)
Site-specific safety plan

Correct answer: Training attendance and comprehension acknowledgment form

A signed training acknowledgment form provides legal documentation that the worker received and comprehended the training.

Question 144: What does OSHA 1926.20 'General Safety and Health Provisions' require of all construction employers?

It only applies to federal construction projects
It is an optional guideline for large contractors only
It solely addresses recordkeeping and reporting requirements
Employers must initiate and maintain safety programs, provide frequent and regular inspections by competent persons, and comply with all applicable standards in Part 1926 (Correct answer)

Correct answer: Employers must initiate and maintain safety programs, provide frequent and regular inspections by competent persons, and comply with all applicable standards in Part 1926

OSHA 1926.20 establishes baseline obligations for all construction employers: maintenance of a safety program, appointment of competent persons, frequency of inspections, and compliance with all applicable Part 1926 standards.

Question 145: Which of the following best describes the 'action level' for noise under OSHA's Hearing Conservation Amendment (29 CFR 1910.95)?

85 dBA as an 8-hour TWA (Correct answer)
90 dBA as an 8-hour TWA
80 dBA as an 8-hour TWA
100 dBA peak sound pressure

Correct answer: 85 dBA as an 8-hour TWA

The OSHA action level for noise is 85 dBA as an 8-hour TWA, which triggers audiometric testing and hearing conservation program requirements.

Question 146: According to OSHA standards for construction (29 CFR 1926), what is the minimum clearance distance that must be maintained from overhead power lines rated 50kV or less for unqualified persons?

20 feet
15 feet
5 feet
10 feet (Correct answer)

Correct answer: 10 feet

OSHA standard 29 CFR 1926.1408, Table A, specifies that for voltages up to 50kV, the minimum clearance distance is 10 feet. This distance is crucial for preventing accidental contact by personnel or equipment like cranes and aerial lifts.

Question 147: At what depth must a registered professional engineer design a protective system for a trench according to OSHA standards?

20 feet (Correct answer)
25 feet
15 feet
10 feet

Correct answer: 20 feet

OSHA requires a protective system designed by a registered professional engineer for trenches 20 feet or deeper.

Question 148: What information is NOT required on an OSHA-compliant confined space entry permit?

Acceptable entry conditions and atmospheric test results
The hazards of the permit space and measures to eliminate or control them
The employer's general liability insurance policy number (Correct answer)
Authorized entrants and the entry supervisor

Correct answer: The employer's general liability insurance policy number

Entry permits must contain safety and operational information including space identification, hazards, atmospheric test results, authorized personnel, and emergency procedures—not financial or insurance data.

Question 149: Which of the following is used to determine lifting index (LI)?

Load weight ÷ weight of worker
Load weight x recommended weight limit (Correct answer)
(Load weight ÷ worker age)2
Load weight ÷ recommended weight limit

Correct answer: Load weight x recommended weight limit

A manual lift's proportionate physical strain and injury risk are measured by the lifting index (LI). The recommended weight limit (RWL) is multiplied by the load weight to determine the LI. For a typical, healthy employee, a LI score of less than 1.0 suggests little risk, while a result of higher than 1.0 denotes a danger of injury during the lift.

Question 150: Under OSHA 1904.7, which treatments are considered 'first aid' and therefore do NOT make an injury recordable?

Prescription-strength medication provided by a doctor
Use of non-prescription medications at non-prescription strength, wound closure using butterfly bandages, use of elastic bandages, and irrigation of the eye with water (Correct answer)
X-rays taken to rule out a fracture
Sutures (stitches) applied by a physician

Correct answer: Use of non-prescription medications at non-prescription strength, wound closure using butterfly bandages, use of elastic bandages, and irrigation of the eye with water

OSHA 1904.7(a) defines first aid as including non-prescription medication at non-prescription strength, wound closure using butterflies or steri-strips, use of elastic bandages, irrigation with eye wash, and similar treatments.

Question 151: Under OSHA's Respiratory Protection Standard (29 CFR 1910.134), which type of respirator provides the highest level of protection?

Self-Contained Breathing Apparatus (SCBA) (Correct answer)
Supplied-air respirator (SAR)
Half-face air-purifying respirator
Full-face air-purifying respirator

Correct answer: Self-Contained Breathing Apparatus (SCBA)

An SCBA provides the highest protection because it supplies its own air source, offering complete independence from the ambient atmosphere and full facial coverage.

Question 152: The 'Catch and Fix' or 'STOP' observation programs used in construction are examples of:

Behavior-based safety (BBS) programs that observe and reinforce safe work practices (Correct answer)
OSHA enforcement programs conducted by compliance officers
Environmental monitoring programs for air quality on job sites
Incident investigation protocols following a recordable injury

Correct answer: Behavior-based safety (BBS) programs that observe and reinforce safe work practices

BBS programs like STOP use structured peer observations to identify at-risk behaviors and reinforce safe ones before incidents occur.

Question 153: What is the maximum noise exposure allowed by OSHA for an 8-hour workday without hearing protection?

85 dBA
95 dBA
90 dBA (Correct answer)
80 dBA

Correct answer: 90 dBA

OSHA's permissible exposure limit (PEL) for noise is 90 dBA as an 8-hour time-weighted average (TWA) under 29 CFR 1926.52.

Question 154: Which OSHA standard specifically governs training requirements for employees exposed to fall hazards in construction?

29 CFR 1926.1060
29 CFR 1926.500
29 CFR 1926.21
29 CFR 1926.503 (Correct answer)

Correct answer: 29 CFR 1926.503

29 CFR 1926.503 establishes fall protection training requirements, including retraining when deficiencies are observed.

Question 155: Under ANSI/ASSP Z10, which element is considered foundational to an occupational health and safety management system?

Personal protective equipment programs
Incident investigation procedures
Management leadership and employee participation (Correct answer)
Emergency response planning

Correct answer: Management leadership and employee participation

ANSI/ASSP Z10 identifies management leadership and employee participation as the foundational element upon which all other safety management system components are built.

Question 156: What is the primary purpose of a pre-task planning (PTP) meeting before beginning a new phase of work?

To identify task-specific hazards and agree on controls before work begins (Correct answer)
To review the project budget and materials needed
To satisfy union contract requirements for daily meetings
To assign overtime pay and schedule breaks

Correct answer: To identify task-specific hazards and agree on controls before work begins

Pre-task planning brings workers and supervisors together before starting work to identify hazards specific to that task and establish agreed-upon controls.

Question 157: A construction worker is performing hot work inside a confined space with documented atmospheric testing. The work is paused for a 30-minute lunch break. Upon return, the worker should:

Have the entry supervisor verbally confirm it is still safe
Re-test the atmosphere before re-entering the space (Correct answer)
Resume work since the permit is still valid
Wait 15 additional minutes as a precaution then re-enter

Correct answer: Re-test the atmosphere before re-entering the space

Atmospheric conditions can change rapidly during breaks, especially with hot work; retesting before re-entry is required to ensure continued safety.

Question 158: During demolition of a pre-1980 building, workers encounter pipe insulation suspected to contain asbestos. What is the FIRST action the CHST should take?

Immediately remove the insulation using standard PPE
Install warning tape around the area and proceed cautiously
Wet the material and continue demolition
Stop work in the affected area and arrange for sampling by a licensed asbestos inspector (Correct answer)

Correct answer: Stop work in the affected area and arrange for sampling by a licensed asbestos inspector

OSHA 29 CFR 1926.1101 requires that suspect asbestos-containing materials be assessed by a competent person before disturbance; work must stop until sampling confirms or rules out ACM.

Question 159: Which administrative control is most effective for reducing cumulative trauma disorders among workers performing repetitive tasks?

Requiring anti-vibration gloves at all times
Scheduling quarterly ergonomic assessments
Implementing job rotation so no single muscle group is overloaded continuously (Correct answer)
Posting MSD hazard warning signs near workstations

Correct answer: Implementing job rotation so no single muscle group is overloaded continuously

Job rotation distributes repetitive loading across different muscle groups, allowing recovery time and reducing cumulative exposure for any single tissue. Anti-vibration gloves (PPE) have limited effectiveness and don't reduce posture or force demands. Signs and periodic assessments are informational — they don't reduce the physical stress directly.

Question 160: Under OSHA's Excavation Standard (29 CFR 1926 Subpart P), what is the minimum depth that requires a protective system unless the excavation is in stable rock?

3 feet
6 feet
4 feet
5 feet (Correct answer)

Correct answer: 5 feet

OSHA requires a protective system (sloping, shoring, or shielding) for excavations 5 feet or deeper unless the excavation is entirely in stable rock.

Question 161: The Haddon Matrix is a systematic tool used in incident investigation. What are its two analytical dimensions?

It analyzes only immediate and root causes in two separate columns
It covers equipment, human, and procedural factors across design and operations phases
Host/Agent/Environment (columns) across Pre-event/Event/Post-event phases (rows) — creating a 3x3 grid to identify intervention opportunities at each phase (Correct answer)
It uses two columns only: worker behavior and environmental conditions

Correct answer: Host/Agent/Environment (columns) across Pre-event/Event/Post-event phases (rows) — creating a 3x3 grid to identify intervention opportunities at each phase

The Haddon Matrix creates a 3×3 grid analyzing Host (human), Agent/Vehicle (energy source), and Environment (physical/social) across pre-event, event, and post-event phases to systematically identify countermeasures.

Question 162: A competent person performs a daily inspection of an excavation, its adjacent areas, and protective systems. When must these inspections be conducted?

Only at the beginning of the work shift.
Only after a rainstorm or other hazard-increasing event.
At the end of the day to prepare for the next shift.
Prior to the start of work and as needed throughout the shift. (Correct answer)

Correct answer: Prior to the start of work and as needed throughout the shift.

According to OSHA 1926.651(k)(1), a competent person must make daily inspections of excavations, adjacent areas, and protective systems. These inspections must occur prior to the start of work, as needed throughout the shift, and after every rainstorm or other hazard-increasing occurrence.

Question 163: After a worker's personal fall arrest system has arrested a fall, what is the required action regarding the equipment?

Remove from service and retire or send to manufacturer for inspection before reuse (Correct answer)
Tag the equipment and allow use for one additional shift only
Inspect and return to service if no visible damage is found
Clean thoroughly, re-inspect, and allow the worker to decide on continued use

Correct answer: Remove from service and retire or send to manufacturer for inspection before reuse

OSHA requires that all components of a PFAS that have been subjected to fall arrest forces be immediately removed from service and not reused unless inspected and deemed serviceable by the manufacturer.

Question 164: What is the minimum tensile strength required for each lanyard or vertical lifeline in a personal fall arrest system?

3,000 pounds
7,500 pounds
5,000 pounds (Correct answer)
10,000 pounds

Correct answer: 5,000 pounds

OSHA 1926.502(d)(9) requires that lanyards and vertical lifelines have a minimum breaking strength of 5,000 pounds.

Question 165: During a confined space entry on a construction site, the attendant's PRIMARY role is to:

Keep track of authorized entrants and initiate rescue procedures without entering (Correct answer)
Perform continuous atmospheric monitoring from inside the space
Monitor the atmosphere inside the space and enter to assist if conditions worsen
Operate ventilation equipment to maintain safe oxygen levels

Correct answer: Keep track of authorized entrants and initiate rescue procedures without entering

The attendant must track entrants and initiate rescue (non-entry rescue or emergency services) but must NOT enter the permit space during an emergency.

Question 166: Under OSHA's Hazard Communication Standard (HazCom), which section of a Safety Data Sheet (SDS) contains first-aid measures?

Section 6
Section 4 (Correct answer)
Section 11
Section 8

Correct answer: Section 4

Section 4 of a 16-section SDS is dedicated to first-aid measures for exposure by different routes.

Question 167: A project safety manager is developing a subcontractor prequalification process. Which criterion is MOST relevant to safety program effectiveness?

Whether the subcontractor uses union or non-union labor
Subcontractor's three-year TRIR and DART rates compared to industry averages (Correct answer)
Number of employees on the subcontractor's payroll
The subcontractor's proximity to the project site

Correct answer: Subcontractor's three-year TRIR and DART rates compared to industry averages

TRIR and DART rates provide objective, industry-benchmarked evidence of a subcontractor's historical safety performance.

Question 168: What is the main advantage of using scenario-based simulations (e.g., tabletop exercises) in construction emergency response training?

They are faster to deliver than traditional classroom instruction
They eliminate the need for written emergency action plans
They allow workers to practice decision-making in a risk-free environment before a real emergency (Correct answer)
They satisfy all OSHA-required emergency drills for the year

Correct answer: They allow workers to practice decision-making in a risk-free environment before a real emergency

Simulation exercises build muscle memory and decision-making skills under simulated stress without real-life consequences of error.

Question 169: When performing a pre-shift inspection, which wire rope condition requires immediate removal from service?

Minor dirt accumulation
Light surface fraying on the outer cover
A kink in the rope (Correct answer)
Slight surface rust on outer wires

Correct answer: A kink in the rope

A kink permanently damages the rope's internal structure and load distribution, making it an immediate rejection criterion per ASME B30.9.

Question 170: Which type of fire extinguisher is most appropriate for a Class D (combustible metal) fire at a construction site?

CO2 (Class B/C)
Dry chemical (ABC)
Water (Class A)
Dry sand or Met-L-X powder (Correct answer)

Correct answer: Dry sand or Met-L-X powder

Class D fires involving combustible metals like magnesium require specialized dry powder agents such as Met-L-X, not standard extinguishers.

Question 171: A utility strike occurs during excavation. Which action should be taken FIRST?

Call 811 (one-call center) immediately
Install additional shoring around the strike location
Continue excavating carefully by hand
Stop work, remove workers, and notify the utility owner (Correct answer)

Correct answer: Stop work, remove workers, and notify the utility owner

Worker safety is paramount — immediately stop work, evacuate all personnel, and then notify the utility company to assess and control the hazard.

Question 172: Under OSHA 29 CFR 1926.21, what are the employer's obligations regarding construction safety training?

Employers must instruct each employee in the recognition and avoidance of unsafe conditions and in the regulations applicable to their work environment (Correct answer)
Training is only required when a worker receives a safety citation
Training requirements only apply to workers with less than 1 year of experience
Employers must provide OSHA 10-hour training to all workers before site entry

Correct answer: Employers must instruct each employee in the recognition and avoidance of unsafe conditions and in the regulations applicable to their work environment

OSHA 1926.21(b)(2) requires employers to instruct each worker to recognize and avoid unsafe conditions and understand the regulations applicable to their work environment, ensuring workers can protect themselves from specific hazards they face.

Question 173: What is the recommended frequency for conducting toolbox talks on an active construction site?

Monthly during all-hands safety meetings
Weekly or before each new task/phase of work (Correct answer)
Only when OSHA conducts an inspection
Quarterly as part of the project safety audit

Correct answer: Weekly or before each new task/phase of work

Toolbox talks should be conducted at least weekly or whenever a new task or phase of work begins to address current and emerging hazards relevant to the crew's activities.

Question 174: Under OSHA 1926.52, at what noise exposure level (as an 8-hour TWA) does a hearing conservation program become mandatory?

95 dBA
85 dBA (the Action Level) (Correct answer)
80 dBA
90 dBA (the PEL)

Correct answer: 85 dBA (the Action Level)

Under OSHA 1926.52 and 29 CFR 1910.95, a full hearing conservation program must be implemented when worker noise exposure reaches the action level of 85 dBA as an 8-hour TWA.

Question 175: In order to achieve a safe lift, which of the following does a mobile crane operator NOT need to be aware of?

The angle of the boom
The width of the jib (Correct answer)
Whether the tires are fully inflated
Whether the outriggers are extended or retracted

Correct answer: The width of the jib

A crane operator must be informed of the crane's capabilities and limitations in order to ensure a safe lift. Outriggers should always be used, and they should be placed on solid, level ground. How much of the crane's maximum rated load it can lift without tipping over will depend on the boom's angle. Finally, to lessen the chance of tipping, the tires must be fully filled.

Question 176: What is the primary purpose of using outrigger pads or crane mats?

To provide a level surface for the crane operator to stand on.
To distribute the crane's load over a larger area to ensure ground stability. (Correct answer)
To protect the ground surface from cosmetic damage.
To increase the crane's lifting capacity beyond its rated limit.

Correct answer: To distribute the crane's load over a larger area to ensure ground stability.

The primary safety function of outrigger pads or mats is to distribute the concentrated load from the outrigger floats over a larger surface area. This prevents the ground from failing, which could lead to the crane becoming unstable and tipping over.

Question 177: When using a tripod and mechanical retrieval system for vertical confined space rescue, the retrieval line must be attached to the entrant's:

Safety belt waist loop
Chest harness front D-ring
Full-body harness chest or back D-ring (Correct answer)
Wrist D-rings

Correct answer: Full-body harness chest or back D-ring

OSHA requires the retrieval line to be attached to the entrant's full-body harness at the chest or back D-ring to allow safe vertical retrieval.

Question 178: Which document should be used to record that individual workers received and understood OSHA-required safety training?

The company's general safety plan without individual names
A verbal confirmation logged only in the supervisor's memory
An email reminder sent before the training session
A signed training attendance record or roster with the date, topic, and trainer's name (Correct answer)

Correct answer: A signed training attendance record or roster with the date, topic, and trainer's name

A signed roster documenting who attended, what was covered, the date, and the trainer provides verifiable proof of training completion.

Question 179: A safety technician calculates the required attenuation for hearing protection in an area with an A-weighted Time-Weighted Average (TWA) noise exposure of 102 dBA. The company policy is to use OSHA's standard formula for estimating workplace protection. If a worker uses earplugs with a Noise Reduction Rating (NRR) of 33, what is the estimated exposure in dBA under the protector?

84 dBA
70 dBA
76 dBA (Correct answer)
69 dBA

Correct answer: 76 dBA

OSHA's formula for estimating the protected A-weighted TWA from an A-weighted measurement is to subtract 7 from the NRR, and then subtract the result from the measured TWA. Calculation: NRR 33 - 7 = 26. Then, 102 dBA - 26 = 76 dBA. This estimated exposure is below the OSHA Permissible Exposure Limit (PEL) of 90 dBA and the action level of 85 dBA.

Question 180: Which condition would require a permit-required confined space entry operation to be terminated immediately?

The entry permit expiration time is approaching within 2 hours
A new worker arrives who was not listed on the original entry permit
A work shift change requiring new entrants to replace current workers
Detection of a prohibited condition such as an oxygen level drop to 18% (Correct answer)

Correct answer: Detection of a prohibited condition such as an oxygen level drop to 18%

A prohibited condition—such as oxygen dropping below 19.5%, flammable gas reaching 10% LEL, or detection of toxic contaminants—requires immediate termination of entry and evacuation of the space.

Question 181: During confined-space entry on a construction site, the atmosphere tests at 19.0% oxygen. How should this be classified?

Oxygen-deficient — entry requires supplied-air or SCBA (Correct answer)
Oxygen-enriched — fire risk is the primary concern
Slightly low — a half-face APR with OV cartridge is sufficient
Normal — no action required since it is close to 20.9%

Correct answer: Oxygen-deficient — entry requires supplied-air or SCBA

OSHA defines an oxygen-deficient atmosphere as less than 19.5% O₂; at 19.0% the space requires supplied-air or SCBA for entry.

Question 182: What does 'safety culture' refer to in construction safety program management?

The organization's OSHA compliance record and number of citations
The shared values, beliefs, norms, and behaviors regarding safety in an organization — including how leadership's visible commitment influences worker behavior and incident rates (Correct answer)
The number of safety posters displayed on the job site
Whether workers have completed OSHA 10 or OSHA 30 training

Correct answer: The shared values, beliefs, norms, and behaviors regarding safety in an organization — including how leadership's visible commitment influences worker behavior and incident rates

Safety culture refers to deep, shared organizational values and norms about safety — including management commitment, worker trust, and behavioral norms that collectively determine how safely people work even when no one is watching.

Question 183: What is the maximum allowable load per scaffold plank for a light-duty scaffold?

10 pounds per square foot
75 pounds per square foot
25 pounds per square foot (Correct answer)
50 pounds per square foot

Correct answer: 25 pounds per square foot

OSHA defines light-duty scaffolds as those designed to carry a maximum of 25 pounds per square foot.

Question 184: Which of the following is the primary purpose of conducting an incident investigation on a construction site?

To complete regulatory paperwork for OSHA and the company's insurer.
To identify root causes and implement corrective actions to prevent recurrence. (Correct answer)
To determine the financial impact of the incident on the project's budget.
To assign blame and discipline responsible employees.

Correct answer: To identify root causes and implement corrective actions to prevent recurrence.

The fundamental goal of an incident investigation is to determine the underlying or root causes to prevent similar incidents from happening in the future. While completing paperwork is a requirement and financial impacts are a concern, the core purpose is prevention, not placing blame, which can discourage reporting and hinder the discovery of systemic safety issues.

Question 185: A CHST discovers that a subcontractor is falsifying injury logs on a project where the CHST works for the general contractor. The CHST's primary ethical obligation is to:

Stay out of the matter since the CHST is employed by the GC, not the subcontractor
Advise the subcontractor's safety officer informally and give them time to self-correct
Report the falsification to OSHA immediately without informing the GC
Notify GC management and document the concern; escalate to OSHA if the GC fails to act (Correct answer)

Correct answer: Notify GC management and document the concern; escalate to OSHA if the GC fails to act

Falsifying OSHA 300 logs is a federal violation (29 CFR 1904). The CHST's ethical duty is to report the concern to GC management with documentation, since the GC has supervisory responsibility over subcontractors on-site. If management fails to act, escalation to OSHA fulfills the duty to uphold regulatory compliance. Going directly to OSHA before internal escalation skips the CHST's professional duty to act through appropriate channels first.

Question 186: A competent person must have which TWO characteristics according to OSHA's definition?

Knowledge to identify existing and predictable hazards AND authority to take corrective action (Correct answer)
First aid certification and supervisor status
A college degree and 5 years of experience
OSHA 30-hour certification and a PE license

Correct answer: Knowledge to identify existing and predictable hazards AND authority to take corrective action

OSHA defines a competent person as one who can identify hazardous conditions and has the authority to eliminate them promptly (29 CFR 1926.32(f)).

Question 187: What is the primary purpose of a Job Hazard Analysis (JHA)?

To train new employees on company policies
To identify hazards before a task begins and establish controls (Correct answer)
To assign blame after an incident occurs
To satisfy OSHA recordkeeping requirements

Correct answer: To identify hazards before a task begins and establish controls

A JHA proactively identifies hazards associated with specific job tasks so controls can be implemented before work starts.

Question 188: What is a Job Hazard Analysis (JHA), and what is the correct sequence of steps for conducting one?

A JHA identifies only fall hazards on construction sites
A JHA is the same as a risk assessment and begins with choosing PPE
A systematic tool to identify hazards for each job step; the sequence is: select the job, break the job into sequential steps, identify hazards for each step, and develop controls for each hazard (Correct answer)
A JHA is only conducted after an incident has occurred

Correct answer: A systematic tool to identify hazards for each job step; the sequence is: select the job, break the job into sequential steps, identify hazards for each step, and develop controls for each hazard

A Job Hazard Analysis breaks a job into sequential steps, identifies hazards associated with each step, and determines appropriate controls to eliminate or reduce those hazards before work begins.

Question 189: What is a 'Toolbox Talk,' and how often should it be conducted on active construction sites?

A brief (10-20 minute) safety discussion on a specific hazard relevant to current work; typically conducted daily or at least weekly depending on project hazards (Correct answer)
A formal 8-hour training class conducted monthly by a certified safety trainer
An OSHA-required document that must be submitted to the project owner monthly
An annual safety meeting required by OSHA for all construction workers

Correct answer: A brief (10-20 minute) safety discussion on a specific hazard relevant to current work; typically conducted daily or at least weekly depending on project hazards

Toolbox talks are brief, job-site safety discussions covering a specific hazard or safety topic relevant to current work. Daily or weekly frequency keeps workers informed of changing hazards as the project progresses.

Question 190: When is a safety monitoring system (SMS) an acceptable sole means of fall protection on a low-slope roof?

Only on roofs with no penetrations
Any time a competent person is available
Whenever fewer than 10 workers are on the roof
Only for roofs 50 feet wide or less with a slope of 4:12 or less (Correct answer)

Correct answer: Only for roofs 50 feet wide or less with a slope of 4:12 or less

OSHA permits SMS as the sole fall protection method only on low-slope roofs 50 feet or less in width.

Question 191: What is the PRIMARY reason for maintaining written safety training records on a construction project?

To meet bonding requirements set by the project owner
To provide evidence of corporate safety culture for marketing purposes
To document compliance with regulatory requirements and verify worker qualifications (Correct answer)
To justify reduced insurance premiums at the end of the policy period

Correct answer: To document compliance with regulatory requirements and verify worker qualifications

Training records serve as objective evidence that the employer met legal obligations under applicable OSHA standards and that workers held the required competencies for their tasks. This documentation is critical during inspections, incident investigations, and litigation.

Question 192: What class of hard hat is required when workers are exposed to high-voltage electrical hazards exceeding 20,000 volts?

Class C — conductive
Class A — general industry
Class B — high voltage
Class E — electrical (Correct answer)

Correct answer: Class E — electrical

ANSI/ISEA Z89.1 Class E (Electrical) hard hats are tested to 20,000 volts and are required for exposures to high-voltage electrical hazards.

Question 193: A construction site has an 8-foot deep trench dug entirely in Type A soil. The competent person has observed that heavy vehicle traffic is causing vibrations near the trench. Which of the following is the correct action for the competent person to take?

Reclassify the soil and adjust the protective system accordingly. (Correct answer)
Slope the trench at an angle of 53 degrees.
No action is needed as Type A soil is the most stable.
Install a warning system for the mobile equipment.

Correct answer: Reclassify the soil and adjust the protective system accordingly.

According to OSHA's soil classification system, a soil cannot be classified as Type A if it is subject to vibration. The competent person must re-evaluate and reclassify the soil, which would likely downgrade it to Type B or C, requiring a change in the protective system (e.g., changing the slope angle or using shoring/shielding).

Question 194: What action must be taken before working on or near a crane's electrical systems?

Post a spotter at the crane base
Notify the site supervisor
Lower the boom to the ground
Apply lockout/tagout procedures (Correct answer)

Correct answer: Apply lockout/tagout procedures

OSHA's lockout/tagout standard (29 CFR 1910.147) requires energy isolation and lockout before any maintenance on electrically powered crane systems.

Question 195: How does adult learning theory (andragogy) differ from pedagogy, and what does it mean for safety training design?

Andragogy refers to online learning only, while pedagogy refers to classroom learning
Andragogy and pedagogy are equivalent approaches with no practical difference for safety training
Andragogy holds that adults learn best when training is self-directed, immediately applicable, experience-based, and problem-centered; pedagogy assumes teacher-directed, subject-centered learning — safety training should follow andragogical principles for better retention and application (Correct answer)
Andragogy applies only to management-level training, not craft worker safety training

Correct answer: Andragogy holds that adults learn best when training is self-directed, immediately applicable, experience-based, and problem-centered; pedagogy assumes teacher-directed, subject-centered learning — safety training should follow andragogical principles for better retention and application

Malcolm Knowles' adult learning theory (andragogy) identifies that adults are self-directed, bring experience to learning, need immediate applicability, and prefer problem-based learning — principles that should shape how construction safety training is designed.

Question 196: A new subcontractor crew speaks primarily Spanish. What is the MOST effective approach to ensure they understand the site safety orientation?

Provide all materials in Spanish and use a bilingual trainer or interpreter (Correct answer)
Post English-only signs and assume workers will ask questions
Waive the orientation since language barriers make it impractical
Give them a written English test and let supervisors explain informally

Correct answer: Provide all materials in Spanish and use a bilingual trainer or interpreter

OSHA requires training to be presented in a language and vocabulary workers understand, so bilingual materials and trainers are necessary.

Question 197: A floor hole cover must be capable of supporting at least how many times the maximum intended load of workers, equipment, and materials?

3 times
1.5 times
4 times
2 times (Correct answer)

Correct answer: 2 times

OSHA requires floor hole covers to support at least twice the maximum intended load to provide an adequate safety factor.

Question 198: What is the required minimum clearance between a crane and an energized power line rated between 50 kV and 200 kV under OSHA 1926.1408?

15 feet (Correct answer)
25 feet
20 feet
10 feet

Correct answer: 15 feet

For power lines rated over 50 kV up to 200 kV, OSHA 1926.1408 Table A requires a minimum clearance of 15 feet between any part of the crane (including load line and load) and the energized line.

Question 199: What action must be taken before an excavation is entered each day or after a rainstorm?

Erect additional barrier fencing around the perimeter
Test air quality for all four atmospheric hazards
Complete a new permit application
Have a competent person inspect for hazardous conditions (Correct answer)

Correct answer: Have a competent person inspect for hazardous conditions

OSHA 1926.651(k) requires a competent person to inspect excavations daily and after any event that could increase hazard potential, such as rain.

Question 200: What must an employer provide if a PFAS cannot be used during steel erection and guardrails are not feasible?

Written documentation of the infeasibility
Safety nets or a positioning device system (Correct answer)
A safety monitor and warning line system
An administrative control plan only

Correct answer: Safety nets or a positioning device system

When conventional fall protection is infeasible in steel erection, safety nets or positioning device systems are the required alternative.

CHST (Construction Health and Safety Technician) Exam

The CHST (Construction Health and Safety Technician) Exam exam validates essential knowledge and skills required for certification or licensure in this field.

200

Questions

240 min

Time Limit

68%

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