OSHA REGULATIONS for SKYLIGHTS
1910.23(a)(4)
Every skylight floor opening and hole shall be guarded by a standard skylight screen or a fixed standard railing on all exposed sides.
1910.23(e)(8)
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. The construction shall be of grillwork with openings not more than 4 inches long or of slatwork with openings not more than 2 inches wide with length unrestricted.
1926.501(b)(4)(i)
Each employee on walking/working surfaces shall be protected from falling through holes (including skylights) more than 6 feet (1.8 m) above lower levels, by personal fall arrest systems, covers, or guardrail systems erected around such holes.
1926.501(b)(4)(ii)
Each employee on a walking/working surface shall be protected from tripping in or stepping into or through holes (including skylights) by covers.
1926.501(b)(4)(iii)
Each employee on a walking/working surface shall be protected from objects falling through holes (including skylights) by covers.
http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9715
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