CHST CHST - Construction Health and Safety Technician Crane and Rigging Safety Questions and Answers 4 — Questions and Answers
Question 1: What is the maximum allowable side pull angle for a standard single-part wire rope sling lift?
- 5 degrees (Correct answer)
- 10 degrees
- 15 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 2: A synthetic web sling must be removed from service if it shows which of the following defects?
- Slight surface discoloration from UV
- Missing or illegible load tag (Correct answer)
- Minor surface abrasion on the edge
- Stiffness from cold temperatures
Correct answer: Missing or illegible load tag
ASME B30.9 requires removal from service of any sling with a missing or illegible identification tag because rated capacity cannot be verified.
Question 3: Which rigging configuration provides the highest vertical load capacity for a given sling rated capacity?
- Single-leg vertical hitch
- Two-leg bridle at 60° from horizontal
- Basket hitch with both legs vertical (Correct answer)
- Choker hitch
Correct answer: Basket hitch with both legs vertical
A basket hitch with both legs vertical doubles the effective load capacity compared to a single vertical hitch, and is more efficient than angled bridles.
Question 4: What action must be taken before working on or near a crane's electrical systems?
- Notify the site supervisor
- Apply lockout/tagout procedures (Correct answer)
- Post a spotter at the crane base
- Lower the boom to the ground
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 5: How should a tag line be used during a crane 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
- To measure the load radius during the lift
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 6: Which condition requires crane operations to be suspended immediately?
- Wind speed reaching 20 mph
- Ambient temperature below 32°F
- Any lightning in the area or wind speed exceeding manufacturer's rated limit (Correct answer)
- Load approaching 75% of rated capacity
Correct answer: Any lightning in the area or wind speed exceeding manufacturer's rated limit
Lightning poses an immediate electrocution risk and wind beyond the manufacturer's rated limit makes the crane structurally unsafe — both require immediate shutdown.
Question 7: Under OSHA 29 CFR 1926.1427, crane operators must be qualified by which method?
- Completing a 40-hour safety course
- Certification by an accredited crane operator testing organization, employer qualification, or military training (Correct answer)
- Holding a valid commercial driver's license
- 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.
What is the maximum allowable side pull angle for a standard single-part wire rope sling lift?