1926.66(b)(5) Dry Type Overspray Collectors - (Exhaust Air Filters)

In conventional dry type spray booths, overspray dry filters or filter rolls, if installed, shall conform to the following:

The spraying operations except electrostatic spraying operations shall be so designed, installed and maintained that the average air velocity over the open face of the booth (or booth cross section during spraying operations) shall be not less than 100 linear feet per minute. Electrostatic spraying operations may be conducted with an air velocity over the open face of the booth of not less than 60 linear feet per minute, or more, depending on the volume of the finishing material being applied and its flammability and explosion characteristics. Visible gauges or audible alarm or pressure activated devices shall be installed to indicate or insure that the required air velocity is maintained. Filter rolls shall be inspected to insure proper replacement of filter media.

The location of filters in a spray booth shall be so as to not reduce the effective booth enclosure of the articles being sprayed.

Space within the spray booth on the downstream and upstream sides of filters shall be protected with approved automatic sprinklers.

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

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. Filters and filter rolls shall not be alternately used for different types of coating materials, where the combination of materials may be conductive to spontaneous ignition.

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.