1.1 This standard is concerned with electrical apparatus with type of protection ' n ', which is not normally capable of igniting a surrounding explosive atmosphere and in which a fault capable of causing ignition is unlikely to occur. When such apparatus is used in an area in which an explosive concentration of gas or vapour is not likely to occur and, if it occurs, will only exist for a short time, the risk of the simultaneous presence of a source of ignition and an explosive atmosphere is consider-ed to be negligible.
1.2 This standard specifies the essential constructional features of electrical apparatus with type of protection ' n ', the test requirements which it shall meet, and the marking to be applied to it.
1.3 Subject to the limitations imposed by the temperature class (see 6 ), this apparatus is suitable for all gases and vapours when mixed with air. It is not intended to be used where there is a hazard due to ignitable dust or fibre.
IS 8289-1976 history
1977IS 8289-1976 Specification for electrical equipment with protection type "n"