California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 7 - General Industry Safety Orders
Group 20 - Flammable Liquids, Gases and Vapors
Article 137 - Spray Coating Operations
Section 5447 - Dry Type Overspray Collectors (Exhaust Air Filters)

(1) Visible gauges or audible alarms or pressure activated devices shall be installed to indicate or insure that the required air velocity is maintained. (See Section 5153). Dry spray booth equipped with a filter roll which is automatically advanced when the air velocity is reduced to that specified in this Section shall be arranged to cause shutdown of spraying operations if the filter roll fails to advance automatically.

(2) Maintenance procedures shall be established to assure replacing filter pads before excessive restriction to air flow occurs. Filter pads shall be inspected after each period of use and clogged filter pads discarded and replaced. Filter rolls shall be inspected to insure proper replacement of filter media.

(3) All discarded filter pads and filter rolls shall be immediately removed to a safe, well detached location or placed in a water-filled metal container and disposed of at the close of the day's operation unless maintained completely in water.

(4) The location of filters in a spray booth shall not reduce the effective booth enclosure of the articles being sprayed.

(5) Space within spray booth on the down stream and up stream sides of filters shall be protected with approved automatic sprinklers.

(6) Filters or filter rolls shall not be used when applying a spray material known to be highly susceptible to spontaneous heating and ignition.

(7) Those parts of the booth which act as supports for, or holders of filters or filter rolls shall be noncombustible.

(8) Clean filters or filter rolls shall be noncombustible or of a type having a combustibility not in excess of Class 2 filters as listed by Underwriters' Laboratories, Inc.

(9) Filters and filter rolls shall not be alternately used for different types of coating materials, where the combination of materials may be conducive to spontaneous ignition. See also Section 5453 (l).