Knowledge of the properties of plastics is essential for designing products, specifying the material to be used, carrying out quality control on finished products, failure analysis and for understanding the structure and behaviour of new materials. Each class of materials has its own specific test procedures, which have developed as the material has evolved. This book concentrates on one area of testing - short-term mechanical tests. These are defined as tests of mechanical properties where the effects of long periods of time and cycling are ignored. This group of tests includes hardness, tensile, compression, shear, flexing, impact and tear and in this book it is also taken to include density and dimensional measurement together with test piece preparation and conditioning. This book will be useful to all those who are already involved in the testing of polymers and it is an ideal guide to those just starting out in the field, whether in academia or industry.