COSS Walking and Working Surfaces 3 — Questions and Answers
Question 1: When inspecting a stepladder, a safety officer notices the spreader bars are bent but the ladder is otherwise intact. What is the correct action?
- Mark the ladder for repair and return to service after straightening
- Remove the ladder from service immediately (Correct answer)
- Allow use only for tasks under 6 feet
- Apply a warning tag and monitor for further damage
Correct answer: Remove the ladder from service immediately
Damaged spreader bars compromise the ladder's structural stability; the ladder must be removed from service immediately until properly repaired or replaced.
Question 2: Under OSHA's walking-working surfaces standard, what is the minimum height of a standard guardrail for general industry?
- 36 inches
- 39 inches
- 42 inches (Correct answer)
- 48 inches
Correct answer: 42 inches
OSHA 1910.29(b)(1) requires the top rail of a guardrail system to be 42 inches (plus or minus 3 inches) above the walking-working surface.
Question 3: An employee is working on a roof with a slope of 4:12. Under OSHA 1926.502, which fall protection method is NOT acceptable for this slope?
- Personal fall arrest system
- Safety net system
- Guardrail system
- Warning line system used alone without other protection (Correct answer)
Correct answer: Warning line system used alone without other protection
A warning line system alone is only acceptable on low-slope roofs and must be combined with a safety monitoring system, guardrails, or PFAS — it cannot stand alone on steeper slopes.
Question 4: Which of the following best defines a 'hole' under OSHA's walking-working surfaces standard?
- Any void in a floor more than 2 inches in diameter
- A gap or void 2 inches or more in its least dimension in a floor, roof, or walking-working surface (Correct answer)
- Any opening in a vertical surface larger than 1 square foot
- An unguarded excavation deeper than 4 feet
Correct answer: A gap or void 2 inches or more in its least dimension in a floor, roof, or walking-working surface
OSHA 1910.21 defines a hole as a gap or void 2 inches or more in its least dimension in a floor, roof, or other walking-working surface.
Question 5: What action is required when a fixed ladder extends more than 24 feet without an intermediate platform or safety device?
- Add a cage around the ladder
- Install a personal fall arrest system or ladder safety system (Correct answer)
- Add a rest platform every 24 feet
- Both a cage and intermediate platforms are required
Correct answer: Install a personal fall arrest system or ladder safety system
OSHA 1910.23 requires fixed ladders over 24 feet to be equipped with a personal fall arrest system or ladder safety system; cages are no longer an accepted fall protection method under the updated standard.
Question 6: A mid-rail in a standard guardrail system must withstand an outward or downward force of at least how many pounds?
- 100 lbs
- 150 lbs (Correct answer)
- 200 lbs
- 250 lbs
Correct answer: 150 lbs
OSHA 1910.29(b)(3) requires midrails, screens, mesh, and intermediate members to withstand a force of at least 150 pounds applied downward or outward.
Question 7: Which condition requires a dockboard or bridgeplate to be secured to prevent movement during loading/unloading?
- Only when the load exceeds 5,000 lbs
- Always, when used for powered industrial truck traffic (Correct answer)
- Only on outdoor docks exposed to weather
- When the dock height difference exceeds 3 inches
Correct answer: Always, when used for powered industrial truck traffic
OSHA requires dockboards used for powered industrial truck (forklift) traffic to be secured to prevent movement, protecting workers from falls between the vehicle and dock.
COSS Walking and Working Surfaces 3
When inspecting a stepladder, a safety officer notices the spreader bars are bent but the ladder is otherwise intact.
What is the correct action?