IS 11064 : 1984 Guide for construction and use of rooms or buildings protected by pressurization for installation of electrical apparatus for explosive gas atmospheres

1 Scope

1.1 This guide defines the conditions in which an electricalapparatus liable to cause an ignition may be used in a room orbuilding situated where flammable gases or vapours may be present,the ingress of these gases or vapours into the room being preventedby maintaining inside it a protective gas at a higher pressure thanthat of the outside atmosphere.

1.2 This guide includes recommendations for the construction,equipping and operation of rooms or buildings and their associatedparts, such as inlet and exhaust ducts for the protective gas, andauxiliary control devices necessary for the satisfactory productionand maintenance of the overpressure.

1.3 This guide also recommends the tests, necessary to show thatthe installation conforms to these recommendations and the markingto be placed on the rooms or buildings.

1.4 This guide concerns only rooms and buildings in the interiorof which there is no internal release (actual or potential) offlammable gases and vapours.

2 References

IS 5572 : Part 1 : 1978 Classification of hazardousareas (other thanmines) for electrical installations:Part 1 Areas having flammable gases and vapours

IS 7389 : Part 1 :1976 Specification for pressurized enclosuresofelectrical equipment for use in hazardous areas:Part 1 Pressurized enclosures with no internal source of flammable gasor vapour