STSC Tool and Equipment Safety 5 — Questions and Answers
Question 1: A supervisor notices a worker using an electric drill with a two-prong plug instead of a three-prong grounded plug. What should the supervisor do?
- Allow use if the cord is undamaged
- Stop work immediately and replace the tool with a properly grounded one (Correct answer)
- Permit use only if a GFCI is on the circuit
- Allow use only for work less than 30 minutes
Correct answer: Stop work immediately and replace the tool with a properly grounded one
Ungrounded power tools pose an electrocution hazard and must be removed from service and replaced with properly grounded or double-insulated tools.
Question 2: What does the color-coding system for abrasive grinding wheels primarily indicate?
- The manufacturer's country of origin
- The wheel's bond type, grit, and maximum operating speed (Correct answer)
- The wheel's age and storage date
- The hazard level of the abrasive material
Correct answer: The wheel's bond type, grit, and maximum operating speed
Grinding wheel markings identify the abrasive type, grit size, grade, structure, and bond type, along with the maximum RPM the wheel can safely handle.
Question 3: Which condition makes it UNSAFE to use a chain hoist or come-along for lifting?
- The chain shows surface rust that can be wiped off
- The hook latch spring is slightly stiff
- The chain links are stretched or deformed (Correct answer)
- The chain is a different color than the housing
Correct answer: The chain links are stretched or deformed
Stretched or deformed chain links indicate overloading or damage that compromises the lifting capacity and can lead to sudden failure under load.
Question 4: Under OSHA 29 CFR 1926, which hand tool is NOT required to be kept free of mushroomed heads?
- Cold chisels
- Drift pins
- Star drills
- Pliers (Correct answer)
Correct answer: Pliers
Pliers do not develop mushroomed heads; however, struck tools like chisels, drift pins, and star drills must have mushroomed heads dressed or replaced to prevent fragment ejection.
Question 5: What is the minimum safe distance a worker should maintain from a powder-actuated tool discharge when it is being operated by another worker?
- 3 feet
- 6 feet
- 10 feet (Correct answer)
- 25 feet
Correct answer: 10 feet
OSHA and manufacturer guidelines specify that workers must stay at least 10 feet away from the muzzle direction of a powder-actuated tool being fired.
Question 6: When using an electric circular saw, what PPE is MOST critical to prevent the most likely serious injury?
- Steel-toed boots
- Cut-resistant gloves
- Safety glasses or goggles (Correct answer)
- Hearing protection
Correct answer: Safety glasses or goggles
Circular saws generate flying debris, chips, and sawdust at high velocity, making eye protection the most critical PPE to prevent serious eye injury.
Question 7: According to OSHA, how often must portable electric tools be inspected by a competent person on a construction site?
- Monthly
- Quarterly
- Before each use (Correct answer)
- Annually
Correct answer: Before each use
OSHA 29 CFR 1926.303 requires that portable electric tools be inspected before each use to identify defects that could cause injury.
STSC Tool and Equipment Safety 5
A supervisor notices a worker using an electric drill with a two-prong plug instead of a three-prong grounded plug.
What should the supervisor do?