When the Walking and Working Surfaces standard changed last year, I focused on the changes that primarily affected my main business - mainly competent person issues, ladders and rope descent systems. Recently, I read an article which pointed out something I had glossed over, namely a major difference in the wording regarding force loads on covers for skylights, which started me thinking. The prior standard said "Skylight screens shall be of such construction and mounting that they are capable of withstanding a load of at least 200 pounds applied perpendicularly at any one area on the screen. They shall also be of such construction and mounting that under ordinary loads or impacts, they will not deflect downward sufficiently to break the glass below them…" - 1910.23 (e)(8) .

That compares to the revised standard which states "Is capable of supporting without failure, at least twice the maximum intended load that may be imposed on the cover at any one time…" - 1810.29(e)(1).

Since Maximum intended load means the total load (weight and force) of all employees, equipment, vehicles, tools, materials, and other loads the employer reasonably anticipates to be applied to a walking-working surface at any one time it appears that systems that rely on static, rather than dynamic testing will not meet the revised standard.

In looking at the fall protection standard we see references to force loads not exceeding 900 pounds. Given the twice the intended maximum load referenced in the revised standard, does that mean that covers need to withstand 1800 pounds if someone were to fall on them? I can only speculate on the answer until OSHA provides a clarification. I am open for suggestions.