SafetyQuestion 97 of 110
A plumber sets an extension ladder to reach a roof vent terminal. Using the 4-to-1 rule, how far should the base be from the wall if the ladder contacts the wall 16 ft up?
a.4 ft
b.2 ft
c.8 ft
d.16 ft
Explanation
The 4-to-1 rule places the base 1 ft out for every 4 ft of working height, so 16 / 4 = 4 ft from the wall. This angle keeps the ladder from sliding out at the base or tipping back. The ladder should also extend at least 3 ft above the roof edge for a safe transition.
Law Reference: 29 CFR 1926.1053Practice all 110 questions free — no signup required.
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