1.1 This specification covers requirements for 10 psi pipe stiffness poly(vinyl chloride) (PVC) closed profile sewer pipe and fittings with integral bell and elastomeric seal joints or plain end pipe with couplings in sizes (18 to 60 in.) based on a co This specification covers requirements for pipe stiffness poly(vinyl chloride) (PVC) closed profile sewer pipe and fittings with integral bell and elastomeric seal joints or plain end pipe with couplings in sizes based on a controlled inside diameter.