What is PAT?
PAT (Photographic Activity Test) is an independent specialist test of storage products for photographs. It has been developed in the United States. It is an accelerated aging test which helps discover potentially harmful chemical reactions that the tested storage product and the main components of photographic emulsion might come into. If a given material is awarded a PAT certificate, it means that it has passed the tests. If it then meets a few additional criteria (e.g. the right pH value), it can be safely used for long-term storage of photographs.