(A) Access hatches. Where shown and required by the details in Appendix A of this chapter, access hatches shall be provided for precast structures. Hatches shall be either single- or double-door with a frame assembly fabricated of aluminum and capable of withstanding a live load of 300 lbs/sq. ft. The doors shall be equipped with heavy-forged brass hinges, stainless steel pins, spring operators and an automatic hold-open bar with release handle which holds the door open at 90 degrees. Each door shall be provided with a lifting handle.
(B) Safety grating.
(1) An aluminum safety grating shall be furnished integral with each hatch to prevent falling when the main hatch lid is opened. The grating shall be designed to withstand a minimum live load of 300 psf. Deflection shall not exceed one-one hundred fiftieth (1/150) of the span.
(2) The design of the hatch must assure that the grate is closed prior to the hatch doors being closed.
(3) Each grate shall be equipped with torsion rod lift assistance for ease of operation, and a hold-open arm shall be included which will lock the grate in the 90-degree position once opened.
(4) The opening arm shall be equipped with a controlled, confined space-entry locking device which will prevent unauthorized entry to the confined space. The safety grating shall be furnished by the same manufacturer as the aluminum hatch to assure compatibility.
(C) Access frames.
(1) Access frames shall be sized as shown on the details in Appendix A of this chapter. Where noted, sizing may be contingent upon recommendations by equipment suppliers as required to provide for equipment removal.
(2) Access frames shall be accurately placed as an integral part of the precast top-slab section.
(3) Access frames shall be protected from direct contact with the concrete by means of a protective coating.
(D) Accepted types. Access hatches and frames shall be type “J” or “JD” as manufactured by the Bilco Company, Series W1R and W2R as manufactured by Halliday Products, or an equal.
(Ord. 2010-3, passed 10-6-2010)