.-(1) No electric apparatus shall be allowed in a zone "0" area:Provided that this sub-rule shall not prohibit the use in a zone "0" area of an intrinsically safe apparatus of a type approved in writing by the Chief Controller and in connection with an intrinsically safe circuit, where use of such apparatus cannot be completely excluded.(2)All electric apparatus installed or used in a zone "1" area shall be either-(i)a flame proof or intrinsically safe apparatus of a type or types approved in writing by the Chief Controller, or(ii)an industrial-type apparatus housed in an enclosure or a room which has been made safe by pressurising or purging with a plenum of atmosphere free from significant concentration of any inflammable gas or vapour and so arranged and inter-locked that in case of failure of the pressurising or purging agent, the electricity supply is automatically cut off or a warning is automatically given to a person in attendance who shall take suitable measures to prevent a hazard.(3)All electric apparatus installed or used in a zone "2" area shall be either-(i)a non-sparking apparatus of a type approved by the Chief Controller; or(ii)an apparatus of any of the types permitted under sub-rule (2).(4)Where the approval of the Chief Controller is sought for any type of electric apparatus for use in hazardous area, the person desirous of manufacturing the apparatus shall submit to the Chief Controller-(i)a comprehensive report accompanied by all necessary drawings, calculations giving references to recognised code or codes followed, full details of design and construction and necessary test certificates from the recognised bodies in respect of the apparatus and its components;(ii)a scrutiny fee of rupees five hundred.
