46 CFR §160.010-5

1. (a)Buoyant apparatus with plastic foam buoyancy must have a plastic foam body with an external protective covering. The body may be reinforced as necessary to meet the tests in § 160.010-7.
2. (b)Plastic foam used in the construction of buoyant apparatus must be a unicellular type accepted by the Commandant (CG-ENG-4) as meeting one of the following:
   1. (1)Subpart 164.015 of this chapter.
   2. (2)MIL-P-19644C (incorporated by reference, see § 160.010-1 of this subpart).
   3. (3)MIL-P-21929B (incorporated by reference, see § 160.010-1 of this subpart).
   4. (4)MIL-P-40619A (incorporated by reference, see § 160.010-1 of this subpart).
3. (c)The external protective covering must be—
   1. (1)Fibrous-glass-reinforced plastic, constructed of a polyester resin listed on the current Qualified Products List for MIL-P-21607E(SH) (incorporated by reference, see § 160.010-1 of this subpart), or accepted by the Commandant (CG-ENG-4) as meeting MIL-P-21607;
   2. (2)Elastomeric vinyl accepted by the Commandant (CG-ENG-4) as meeting § 160.055-3(j) of this chapter; or
   3. (3)Any other material accepted by the Commandant (CG-ENG-4) as providing equivalent protection for the body of the apparatus.