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Subchapter 7. General Industry Safety Orders
Group 20. Flammable Liquids, Gases and Vapors
Article 137. Spray Coating Operations

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§5449. Electrical and Other Sources of Ignition.

(a) All electrical equipment, open flames and other sources of ignition shall conform to the requirements of this Section, except as follows:

 (1) Electrostatic apparatus shall conform to the requirements of Sections 5454 and 5455. 

 (2) Drying, curing and fusion apparatus shall conform to the requirements of Section 5456. 

 (3) Automobile undercoating spray operations in garages shall conform to the requirements of Section 5459. 

 (4) Powder coating equipment shall conform to the requirements of Section 5460. 

 (5) Finishing operations as described in Subsection (m). 

(b) There shall be no open flame, spark producing equipment or exposed surfaces exceeding the ignition temperature of the material being sprayed in any spraying area nor within 20 feet thereof, unless separated by a partition.

(c) Space heating appliances, steam pipes or hot surfaces shall not be located in a spraying area where deposits of combustible residues may readily accumulate and be ignited.

(d) Electrical wiring and equipment shall conform to the provisions of this Section and shall otherwise be in accordance with the California Electrical Safety Orders.

(e) Unless specifically approved for locations containing both deposits of readily ignitible residue and explosive vapors, there shall be no electrical equipment in any spraying area, whereon deposits of combustible residues may readily accumulate, except wiring in rigid metal conduit, Type MI cable, or in metal boxes or fittings containing no taps, splices or terminal connections.

(f) Electrical wiring and equipment not subject to deposits of combustible residues but located in a spraying area shall be of explosion-proof or other type approved for Class I, Division 1, Group D locations and shall otherwise conform to the provisions of the Electrical Safety Orders for Class I, Division 1 locations.

(g) Equipment within twenty feet horizontally and ten feet vertically, of any spraying operation and not enclosed in a spray booth, shall not pro duce sparks under normal operating conditions, and shall otherwise conform to the provisions of the Electrical Safety Orders for Class I, Division 2, locations. See Figure SB-1.

Figure SB-1

(h) When spraying areas are illuminated through glass panels or other transparent materials, only fixed lighting units shall be used as a source of illumination. Panels shall isolate the spraying area from the area in which the lighting unit is located, and shall be of a noncombustible material of such a nature or so protected that breakage will be unlikely. Panels shall be so arranged that normal accumulations of residue on the exposed surface of the panel will not be raised to a dangerous temperature to cause vapors and/or ignition by radiation or conduction from the source of illumination.

(i) Electric lamps outside of, but within twenty feet of any spraying area and not separated by a partition, shall be totally enclosed to prevent the falling of hot particles and shall be protected from mechanical injury by guards or by location.

(j) Portable electric lamps shall not be used in any spraying area during spraying operations. Portable electric lamps, if used during cleaning or repairing operations, shall be of the type approved for Class I, Group D, Division 1 locations.

(k) All metal parts of spray booths, exhaust ducts and piping systems conveying flammable or combustible liquids or aerated solids shall be electrically grounded in an effective and permanent manner.

(l) Airless high fluid pressure spray guns and any conductive object being sprayed shall be electrically grounded.

Exception: Equipment specifically intended to be operated at other than ground potential.

(m) Where the product to be sprayed is brought into a spraying area, removed from it, or manipulated while there, by a self-powered vehicle capable of producing ignition, the vehicle shall not be activated while in the area unless the spraying operation is stopped, the ventilation system is in operation and the area has been purged of vapors to ensure a nonflammable atmosphere.

    Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.  

1. Amendment of subsections (a)(1) and (4) and (m) filed 3-2-76; effective
thirtieth day thereafter (Register 76, No. 10).

2. Amendment filed 7-16-76; effective thirtieth day thereafter (Register 76, 
No. 29).

3. Amendment of subsection (l ) filed 7-8-85; effective thirtieth day
thereafter (Register 85, No. 28).

4. Amendment of subsections (d), (f)-(i) and (k)-(m) filed 12-5-86; effective
thirtieth day thereafter (Register 86, No. 51).

5. Change without regulatory effect providing more legible illustration for
Figure SB-1 filed 3-2-2009 pursuant to 
section 100, title 1, California Codeof Regulations (Register 2009, No. 10).

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