STSC Hazard Identification and Control 2 — Questions and Answers

Question 1: The hierarchy of hazard controls lists controls in what order from most to least effective?

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

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

NIOSH's hierarchy of controls ranks from most effective (elimination) to least effective (PPE), guiding hazard control selection.

NIOSH's Hierarchy of Controls ranks control strategies from most to least effective: (1) Elimination — physically remove the hazard; (2) Substitution — replace the hazardous material or process; (3) Engineering controls — isolate workers from the hazard (guards, ventilation, barriers); (4) Administrative controls — change how work is done (procedures, rotation, scheduling); (5) PPE — protect the worker from the hazard (last resort). Employers should implement higher-level controls whenever feasible, using PPE only when other controls are not sufficient or while controls are being implemented.

Question 2: A Job Hazard Analysis (JHA) or Job Safety Analysis (JSA) is most effective when:

Completed by management only without worker input
Developed by the supervisor and workers who perform the task (Correct answer)
Performed once for each type of job site
Filed in the safety office and referenced only after incidents

Correct answer: Developed by the supervisor and workers who perform the task

JHAs are most effective when developed collaboratively with workers who actually perform the task, as they have firsthand knowledge of the hazards.

A Job Hazard Analysis (JHA) is a systematic process to identify hazards associated with each step of a job task and determine appropriate controls. It is most effective when: developed collaboratively with workers who perform the task (they know the real hazards); reviewed before each task begins; updated when tasks or conditions change; used as a training tool; and signed by workers to confirm they understand the hazards and controls. Worker participation increases hazard identification quality and worker buy-in for the controls.

Question 3: An 'engineering control' for controlling a noise hazard would be:

Requiring workers to wear earplugs
Installing sound-dampening enclosures around loud machinery (Correct answer)
Rotating workers to limit noise exposure time
Posting 'Noise Hazard Area' warning signs

Correct answer: Installing sound-dampening enclosures around loud machinery

Engineering controls physically modify the work environment to reduce hazard exposure — in this case, enclosing the noise source.

Engineering controls for noise include: enclosing the noise source in a sound-dampening cabinet; mounting machinery on vibration-dampening mounts; installing mufflers on engines and pneumatic tools; using quieter alternative equipment; installing sound-absorbing barriers; and isolating noise sources from workers. These controls reduce noise at the source before it reaches workers. Administrative controls (rotation, scheduling) and PPE (earplugs, earmuffs) are less preferred because they rely on human compliance rather than passive protection.

Question 4: When should a pre-task safety plan be reviewed on a construction site?

Only before the project begins
Every morning at the beginning of each shift (toolbox talk) (Correct answer)
Monthly during safety committee meetings
Only after an incident or near miss

Correct answer: Every morning at the beginning of each shift (toolbox talk)

Pre-task safety briefings (toolbox talks) should occur at the start of each shift to address daily hazards specific to that day's work.

Construction sites are dynamic environments where hazards change constantly (new work activities, weather conditions, equipment positions, personnel). Pre-task safety briefings (toolbox talks, daily safety meetings) conducted at the start of each shift ensure workers are informed about: that day's specific hazards; changes in site conditions; new workers on site; weather-related hazards; current JHAs for tasks being performed; and any near misses or incidents from previous shifts. This practice is a cornerstone of proactive safety culture.

Question 5: The term 'near miss' in construction safety refers to:

A close call where no injury or damage occurred but could have (Correct answer)
A minor injury that didn't require medical treatment
A construction defect caught during inspection
Equipment that barely passed its inspection criteria

Correct answer: A close call where no injury or damage occurred but could have

A near miss is an unplanned event that did not result in injury or damage but had the potential to do so under slightly different circumstances.

Near misses (also called close calls or dangerous occurrences) are events where no harm occurred but where the potential for injury, illness, or damage existed. Research (Heinrich's Triangle and subsequent studies) shows that for every serious injury there are many more minor injuries, and many more near misses. Investigating and correcting near miss events is one of the most cost-effective safety interventions because it addresses root causes before they result in injuries. Workers must be encouraged to report near misses without fear of punishment.

Question 6: OSHA's General Duty Clause (Section 5(a)(1) of the OSH Act) requires employers to:

Follow only specific OSHA standards applicable to their industry
Provide a workplace free from recognized hazards likely to cause death or serious physical harm (Correct answer)
Post OSHA 300 logs at all times
Conduct quarterly safety audits

Correct answer: Provide a workplace free from recognized hazards likely to cause death or serious physical harm

The General Duty Clause requires employers to address recognized hazards even when no specific OSHA standard covers that hazard.

Section 5(a)(1) of the OSH Act (the General Duty Clause) states that each employer shall furnish a place of employment free from recognized hazards that are causing or are likely to cause death or serious physical harm to employees. OSHA uses this clause to cite employers for hazards not covered by a specific standard, provided: (1) the employer or industry recognizes the hazard; (2) the hazard is likely to cause death or serious physical harm; and (3) a feasible means to eliminate/materially reduce the hazard exists.

STSC Hazard Identification and Control 2

The hierarchy of hazard controls lists controls in what order from most to least effective?