This International Standard specifies a method for the determination of density of pipes and fittings of unplasticized polyvinyl chloride (PVC) and lays down the permissible limits for this density. The material from which the pipes and fittings are made is essentially polyvinyl chloride to which only the additives required for their manufacture have been added. This International Standard does not apply to pipes and fittings made from compounds containing fillers, or to cellular products.