a primary deck covering is the first layer of a floor construction which is applied directly on top of the deck plating and is inclusive of any primary coat, anti-corrosive compound or adhesive which is necessary to provide protection or adhesion to the deck plating. Other layers in the floor construction above the deck plating are floor coverings.
Where a floor covering is required to be low flame-spread, all layers shall comply with part 5. If the floor covering has a multilayer construction, the Administration may require the tests to be conducted for each layer or for combinations of some layers of the floor coverings. Each layer separately, or a combination of layers (i.e. the test and approval are applicable only to this combination), of the floor covering shall comply with this part. When a primary deck covering is required to be not readily ignitable and is placed below a floor covering, the primary deck covering shall comply with part 6. When the primary deck covering is also the exposed surface, it shall comply with this part. Primer or similar thin film of paint on deck plating need not comply with the above requirements of part 6.
