- Q.Do the listed weight limits
for ladders and scaffold planks include a safety
factor? If so, how much weight can be added beyond the
listed weight until failure occurs?
A.Alan Kline, president of
Lynn Ladder and Scaffolding Co., Lynn, Mass.,
responds: As a general rule of thumb, OSHA
requires ladders and scaffold planks to be designed
with a 4-to-1 safety factor. That means that under
test conditions, they must be able to support four
times their weight rating without failing.
As to when any particular model might fail, that
depends on many factors. Overloading any ladder or
scaffold plank is a violation of OSHA