MIL-P-21929C, MILITARY SPECIFICATION: PLASTIC MATERIAL, CELLULAR POLYURETHANE, FOAM-IN-PLACE, RIGID (2 POUNDS PER CUBIC FOOT) (15 JAN 1991)

MIL-P-21929C, MILITARY SPECIFICATION: PLASTIC MATERIAL, CELLULAR POLYURETHANE, FOAM-IN-PLACE, RIGID (2 POUNDS PER CUBIC FOOT) (15 JAN 1991)., This specification covers only one class of foam, nominal density - 2.0 pounds per cubic foot (lb/ft3), rigid unicellular polyurethane foam, and the materials required for preparation by the foam-in-place method.