A portable ladder is used to access a mezzanine landing. How far must the side rails extend above the upper landing surface unless equivalent secure access is provided?
Correct Answer
B) 3 ft
Portable ladder side rails used for upper-landing access must extend at least 3 ft above the landing surface unless the ladder is secured and a grasping device is provided. Other choices are too short or unrelated height values.
Why This Is the Correct Answer
Portable ladder side rails used for upper-landing access must extend at least 3 ft above the landing surface unless the ladder is secured and a grasping device is provided. Other choices are too short or unrelated height values.
Why the Other Options Are Wrong
Option A: 12 in.
Choice A (12 in.) is rejected because 12 in. is not the OSHA ladder setup, extension, or access dimension cited here.
Option C: 5 ft
The trap in C is 5 ft. That selection is wrong because 5 ft is not the OSHA ladder setup, extension, or access dimension cited here.
Option D: 6 ft
Choice D gives 6 ft. Its specific error: 6 ft is not the OSHA ladder setup, extension, or access dimension cited here.
Memory Technique
Use a redline memory cue for portable ladder extension: the stem's condition unlocks 3 ft.
Reference Hint
Open 29 CFR 1926 OSHA Construction Standards; use 29 CFR 1926.1053(b)(1) to confirm that Portable ladder side rails used for upper-landing access must extend at least 3 ft above the landing surface unless the ladder is secured and a grasping device is provided.
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