Scope. This article shall apply to the following areas where:
1) Category 1, 2, or 3 liquids with a flash point below 100oF (37.8oC) (formerly designated as Class I) are stored or handled.
2) Category 3 liquids with a flash point greater than or equal to 100oF (37.8oC) and less than 140oF (60oC) (formerly designated as Class II) are stored or handled at or above their flash point.
3) Category 4 liquids or liquids with a flash point greater than or equal to 199.4oF (93oC) (both formerly designated as Class III) are stored or handled at temperatures at or above their flash points.
For areas where only Category 3 liquids with a flash point greater than or equal to 100oF (37.8oC) or Category 4 liquids or liquids with a flash point greater than or equal to 199.4oF (93oC) are stored or handled at a temperature below their flash points, the electrical equipment may be installed in accordance with the provisions of the California Electrical Safety Orders for ordinary locations; however, care shall be used in locating electrical apparatus to prevent hot metal from falling into open equipment.
(a) All electrical equipment and wiring shall be of a type specified by and shall be installed in accordance with the California Electrical Safety Orders and Title 24, Part 3, California Electrical Code, Chapter 5, Special Occupancies.
(b) In the application of classified areas, a classified area shall not extend beyond an unpierced floor, wall, roof or other solid partition.
(c) Where the provisions of this article require the installation of electrical equipment suitable for Class I, Division 1 or Division 2 locations, ordinary electrical equipment including switchgear may be used if installed in a room or enclosure which is maintained under positive pressure with respect to the classified area. Ventilation make-up air shall be uncontaminated by flammable vapors.
(1) Pressurizing or purging of classified areas shall be in compliance with NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2008 Edition (NFPA 496-2008), which is herein incorporated by reference.
(d) The extent of electrical area classifications shall be as contained in Title 24, Part 3, Article 515. Bulk Storage Plant, pertaining to Class I locations.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
1. Articles 140-148 (Sections 5530-5629, not consecutive) filed 11-28-75; effective thirtieth day thereafter (Register 75, No. 48).
2. Amendments filed 7-16-76; effective thirtieth day thereafter (Register 76, No. 29).
3. Amendment of section heading, section and Note filed 7-6-2015; operative 10-1-2015 (Register 2015, No. 28).