Processors and users of plastics often need to determine the chemical nature of a plastics specimen. This highly practical and useful manual, now in a fifth revised and supplemented edition, will enable you to determine the class of plastic of a particular specimen. No extensive knowledge of chemistry is required and yet it is more complex than a simple tabular compilation. This manual is a handy and highly effective tool for many practical situations. An additional supplement is a chapter that shows strategies for identifying historical plastic objects; this is of particular interest for assemblers and collectors, and conservators.