Section 408.42640. Installation of metal decking.

(1) Except as provided in R 408.42648(1), metal decking shall be laid tightly  and   immediately  secured  upon   placement    to   prevent accidental movement or displacement.

(2)   During initial placement, metal  decking   panels  shall  be   placed  to ensure full support by structural members.

(3)   Derrick floors.  A derrick floor shall be fully decked     or    planked and the steel member connections completed to support the intended floor loading.

(4)    Temporary loads placed on a derrick floor shall be       distributed     over the underlying support members so as to prevent local overloading  of  the deck material.

(5)   Temporary flooring shall comply with all of the following provisions:

(a)    Consist of either wood planking which is   not    less   than     2      inches thick, undressed, full size or metal decking or grating of equivalent strength.

(b)   Cover the entire area, except for access openings.

(c)   Be secured against displacement.

(d)  Be capable of carrying the maximum intended working load.

(6)   Planking of  temporary   floors  shall  comply  with     both     of      the following provisions:

(a)   Extend beyond an end bearer not less than 6 inches  nor   more    than 12 inches.

(b)   Overlap any intermediate bearer by a  minimum  of  12    inches.      (See figure 1.) Figure 1 reads as follows:

Figure for 408.42640

(7)    When gathering and stacking temporary floor planks, the planks shall be removed successively, working toward the last panel of the temporary floor so that the work is always done from the planked floor.

(8)   When gathering and stacking temporary floor planks from the last panel, employees assigned to such work shall be protected as specified in R 408.42645.

History: 1985 AACS; 2002 AACS.