Current Japanese standards for flammability tests on electric cables

This paper outlines the flammability test methods and requirements for electric cables specified in some Japanese standards. Only two different methods of a small‐scale flame test as specified in Clause 28 of JIS C 3005 are applied to electric cables for general use, and whether or not the flammability test should be conducted and which method should be adopted depends on the type of cables, both of which are specified in each separate standard. Cables for electrical equipment of ships have to pass another small‐scale flame test as prescribed in Section 6.7 of JIS C 3410. A flame test method for flame‐retardant telecommunication cables has been introduced in JIS C 3521. This specifies a vertical open tray flame test on grouped cables, almost in accordance with IEEE Standard 383. In addition to the method for a vertical open tray flame test, one for a vertical closed duct flame test on grouped cables is also specified in a Japanese Cable Makers' Association Standard, i.e. JCS 366. Some flame‐retardance requirements for electric cables in Japan are listed and discussed.