ISO/R 1326:1970 PDF

Describes a method determining the relative flammability and the burning rate of plastics in the form of sheets or films of thickness between 1.5 mm and 0.05 mm. A strip of film is clamped at one end and allowed to hang down vertically. The flammability and burning rate of the film are assessed after an attempt has been made to ignite the lower end of the film with a defined gas flame. The tested materials are classified in three categories: 1) the specimen does not ignite; 2) the flame extinguishes befor reaching the upper gauge mark; 3) the specimen burns, melts off or is charred up to the upper gauge mark.