Title 29

SECTION 1910.126

1910.126 Additional requirements for special dipping and coating operations.

§ 1910.126 Additional requirements for special dipping and coating operations.

In addition to the requirements in §§ 1910.123 through 1910.125, you must comply with any requirement in this section that applies to your operation.

(a) What additional requirements apply to hardening or tempering tanks?

(1) You must ensure that hardening or tempering tanks:

(i) Are located as far as practicable from furnaces;

(ii) Are on noncombustible flooring; and

(iii) Have noncombustible hoods and vents (or equivalent devices) for venting to the outside. For this purpose, vent ducts must be treated as flues and kept away from combustible materials, particularly roofs.

(2) You must equip each tank with an alarm that will sound if the temperature of the liquid comes within 50 °F (10 °C) of its flashpoint (the alarm set point).

(3) When practicable, you must also provide each tank with a limit switch to shut down the conveyor supplying work to the tank.

(4) If the temperature of the liquid can exceed the alarm set point, you must equip the tank with a circulating cooling system.

(5) If the tank has a bottom drain, the bottom drain may be combined with the oil-circulating system.

(6) You must not use air under pressure when you fill the dip tank or agitate the liquid in the dip tank.

(b) What additional requirements apply to flow coating? (1) You must use a direct low-pressure pumping system or a 10-gallon (38 L) or smaller gravity tank to supply the paint for flow coating. In case of fire, an approved heat-actuated device must shut down the pumping system.

(2) You must ensure that the piping is substantial and rigidly supported.

(c) What additional requirements apply to roll coating, roll spreading, or roll impregnating? When these operations use a flammable liquid that has a flashpoint below 140 °F (60 °C), you must prevent sparking of static electricity by:

(1) Bonding and grounding all metallic parts (including rotating parts) and installing static collectors; or

(2) Maintaining a conductive atmosphere (for example, one with a high relative humidity) in the vapor area.

(d) What additional requirements apply to vapor degreasing tanks? (1) You must ensure that the condenser or vapor-level thermostat keeps the vapor level at least 36 inches (91 cm) or one-half the tank width, whichever is less, below the top of the vapor degreasing tank.

(2) When you use gas as a fuel to heat the tank liquid, you must prevent solvent vapors from entering the air-fuel mixture. To do this, you must make the combustion chamber airtight (except for the flue opening).

(3) The flue must be made of corrosion-resistant material, and it must extend to the outside. You must install a draft diverter if mechanical exhaust is used on the flue.

(4) You must not allow the temperature of the heating element to cause a solvent or mixture to decompose or to generate an excessive amount of vapor.

(e) What additional requirements apply to cyanide tanks? You must ensure that cyanide tanks have a dike or other safeguard to prevent cyanide from mixing with an acid if a dip tank fails.

(f) What additional requirements apply to spray cleaning tanks and spray degreasing tanks? If you spray a liquid in the air over an open-surface cleaning or degreasing tank, you must control the spraying to the extent feasible by:

(1) Enclosing the spraying operation; and

(2) Using mechanical ventilation to provide enough inward air velocity to prevent the spray from leaving the vapor area.

(g) What additional requirements apply to electrostatic paint detearing? (1) You must use only approved electrostatic equipment in paint-detearing operations. Electrodes in such equipment must be substantial, rigidly supported, permanently located, and effectively insulated from ground by nonporous, noncombustible, clean, dry insulators.

(2) You must use conveyors to support any goods being paint deteared.

(3) You must ensure that goods being electrostatically deteared are not manually handled.

(4) Between goods being electrostatically deteared and the electrodes or conductors of the electrostatic equipment, you must maintain a minimum distance of twice the sparking distance. This minimum distance must be displayed conspicuously on a sign located near the equipment.

(5) You must ensure that the electrostatic equipment has automatic controls that immediately disconnect the power supply to the high-voltage transformer and signal the operator if:

(i) Ventilation or the conveyors fail to operate;

(ii) A ground (or imminent ground) occurs anywhere in the high-voltage system; or

(iii) Goods being electrostatically deteared come within twice the sparking distance of the electrodes or conductors of the equipment.

(6) You must use fences, rails, or guards, made of conducting material and adequately grounded, to separate paint-detearing operations from storage areas and from personnel.

(7) To protect paint-detearing operations from fire, you must have in place:

(i) Automatic sprinklers; or

(ii) An automatic fire-extinguishing system conforming to the requirements of subpart L of this part.

(8) To collect paint deposits, you must:

(i) Provide drip plates and screens; and

(ii) Clean these plates and screens in a safe location.

[64 FR 13909, Mar. 23, 1999, as amended at 77 FR 17777, Mar. 26, 2012]