Fixed wooden ladders are prohibited. Where such ladders exist they shall be replaced with one of the following:

(1) Noncombustible conventional stairway with a slope of not more than 60 degrees from horizontal.

(2) Noncombustible collapsible (retractable) stair.

(3) Noncombustible fixed vertical ladders complying with ANSI A14.3, Standard for Ladders, Fixed and Safety Requirements.

(4) Horizontal hatch-type covers.

(a) While facing the ladder, covers shall be hinged and located so as to open to the left or right side of the opening.

(b) The cover shall be provided with a mechanical-assist means to open (e.g., springs, hydraulic, counterweighted, etc.).

(c) The cover shall be constructed of noncombustible material where required to be replaced.

(d) Where a fixed ladder is provided:

(i) Handrails shall be located on the roof on both sides of the opening in line with the access ladder. They shall extend not less than 914.4 mm (36 in.) in height above the roof level. They shall be located as to provide easy reach from the top of the ladder.

(ii) Means shall be provided to hoist tools and materials to the roof level once the hatch cover is open.