A non-self-supporting ladder is leaned against a wall for temporary access. Which setup matches the standard 4-to-1 ladder angle rule?
Correct Answer
C) Base 1 ft out for every 4 ft of working length
A non-self-supporting ladder is set so the horizontal distance from top support to foot is about one-fourth of the working length, commonly stated as 4-to-1. Other choices make the ladder too flat or too steep.
Why This Is the Correct Answer
A non-self-supporting ladder is set so the horizontal distance from top support to foot is about one-fourth of the working length, commonly stated as 4-to-1. Other choices make the ladder too flat or too steep.
Why the Other Options Are Wrong
Option A: Base 1 ft out for every 2 ft of working length
In general project requirements, Base 1 ft out for every 2 ft of working length is the wrong selection for Portable ladder angle: Base 1 ft out for every 2 ft of working length is not the OSHA ladder setup, extension, or access dimension cited here.
Option B: Base 1 ft out for every 3 ft of working length
The trap in B is Base 1 ft out for every 3 ft of working length. That selection is wrong because Base 1 ft out for every 3 ft of working length is not the OSHA ladder setup, extension, or access dimension cited here.
Option D: Base 1 ft out for every 8 ft of working length
Choice D (Base 1 ft out for every 8 ft of working length) is rejected because Base 1 ft out for every 8 ft of working length is not the OSHA ladder setup, extension, or access dimension cited here.
Memory Technique
Treat portable ladder angle like a labeled shelf; only the matching condition belongs with Base 1 ft out for every 4 ft of working length.
Reference Hint
Open 29 CFR 1926 OSHA Construction Standards; use 29 CFR 1926.1053(b)(5)(i) to confirm that A non-self-supporting ladder is set so the horizontal distance from top support to foot is about one-fourth of the working length, commonly stated as 4-to-1.
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