scope:

This standard is intended to be used in conjunction with FM Approvals Examination Standard 3600 - Electrical Equipment for Use in Hazardous (Classified) Locations - General Requirements which includes the general requirements that apply to all types of protection for electrical equipment for use in hazardous (classified) locations. This standard contains the basic requirement for the construction and testing of purged and pressurized electrical equipment available in the following configurations:

• Purged and pressurized electrical equipment which are not occupied portions of buildings (control rooms)

• Purged and pressurized electrical equipment having an internal source of gas or vapor.

Note: the requirements of this standard do not include purged or pressurized control rooms.

Purpose

This standard serves as the basis for certification of electrical equipment for use in hazardous (classified) locations employing the type of protection defined as "Purged and Pressurized."