1.1 ,This specification covers the classification and identification of rigid plastic compounds intended for use in making nonpressure piping products composed of (1) poly(vinyl chloride) polymer, (2) chlorinated poly(vinyl chloride) polymer, or (3) vinyl chloride copolymers, and the necessary compound ingredients. Compounding ingredients consist of lubricants, stabilizers, non-poly(vinyl chloride) resin modifiers, colorants or pigments, or both, fibrous or nonfibrous reinforcements, or fillers.