CHST CHST - Construction Health and Safety Technician Crane and Rigging Safety Questions and Answers 2 — Questions and Answers
Question 1: What is the primary purpose of a critical lift plan on a construction site?
- To document all lifts exceeding 75% of the crane's rated capacity or involving unusual hazards (Correct answer)
- To satisfy insurance requirements for general contractor liability
- To replace the need for a certified crane operator during complex lifts
- To eliminate the requirement for a signal person during hoisting operations
Correct answer: To document all lifts exceeding 75% of the crane's rated capacity or involving unusual hazards
A critical lift plan addresses lifts that approach the crane's capacity limits or involve special hazards, requiring detailed pre-lift engineering and safety analysis.
Question 2: When must a designated rigger be used according to OSHA crane and derrick standards?
- Only when lifting loads over 50 tons
- Whenever workers are within the fall zone and the load is being hooked, unhitched, or guided (Correct answer)
- Only during night shift operations
- When the crane operator cannot see the load at any point
Correct answer: Whenever workers are within the fall zone and the load is being hooked, unhitched, or guided
OSHA 29 CFR 1926.1425 requires a qualified rigger when employees are in the fall zone during hooking, unhooking, or guiding the load.
Question 3: What does the term 'sling angle factor' refer to in rigging operations?
- The maximum swing radius permitted for a mobile crane
- The reduction in sling capacity as the angle between the sling leg and the horizontal decreases (Correct answer)
- The increase in lifting capacity when using wire rope versus synthetic slings
- The required angle of the outrigger pads relative to the ground surface
Correct answer: The reduction in sling capacity as the angle between the sling leg and the horizontal decreases
As the sling angle from horizontal decreases (legs spread wider), the tension on each sling leg increases, reducing the overall rated capacity of the sling arrangement.
Question 4: Which inspection is required before each shift for wire rope slings used in construction rigging?
- A documented third-party inspection with load testing
- A visual inspection by a competent person for damage, kinks, bird-caging, and corrosion (Correct answer)
- Only a monthly inspection logged in the crane maintenance book
- An ultrasonic thickness test of each wire strand
Correct answer: A visual inspection by a competent person for damage, kinks, bird-caging, and corrosion
OSHA requires that wire rope slings be visually inspected before each use by a competent person to identify defects such as kinking, crushing, bird-caging, or broken wires.
Question 5: What is the main hazard associated with side-loading a crane boom?
- It causes excessive fuel consumption in the crane engine
- It can create lateral stress the boom was not designed to handle, leading to structural failure (Correct answer)
- It automatically triggers the anti-two-block device
- It reduces ground bearing pressure under the outriggers
Correct answer: It can create lateral stress the boom was not designed to handle, leading to structural failure
Side-loading applies lateral forces to the boom that exceed its design parameters, which can cause the boom to buckle or collapse catastrophically.
Question 6: What action should a CHST recommend when a rigging hardware component has no legible manufacturer identification or rated load marking?
- Use the component only for loads under 500 pounds
- Apply a generic load rating based on the component's physical size
- Remove the component from service immediately until it can be properly identified and rated (Correct answer)
- Spray-paint a new load rating based on field estimation
Correct answer: Remove the component from service immediately until it can be properly identified and rated
Rigging hardware without legible identification or load ratings cannot be verified as safe for any specific load and must be removed from service per OSHA and ASME standards.
CHST CHST - Construction Health and Safety Technician Crane and Rigging Safety Questions and Answers 2
What is the primary purpose of a critical lift plan on a construction site?