N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 12-2.4

Current through Register Vol. 46, No. 50, December 11, 2024

Section 12-2.4 - Open surface tank operations

(a) General. Open surface tank operations creating dangerous air contaminants shall be provided with ventilation to control such contaminants. (See Industrial Code Part [Rule No.] 18.)

(b) Classes of operations. Open surface tank operations are classified into groups in accordance with both hazard potential and rate of contaminant release as set forth in section 18.14 of Industrial Code Part (Rule No.) 18.

(c) Humidity control. When heat is added to the workroom to prevent the condensation of water vapor evaporated from open tanks into mist, such additional heat shall be so controlled that it does not raise the wet bulb temperature in the lower six feet of the workroom above 80 degrees Fahrenheit.

(d) Clean-out doors. Tanks or machines used for cleaning by solvents and having a surface vapor area of more than two square feet shall be equipped with suitable clean-out or sludge doors located near the bottom of each tank or still. Such doors shall be constructed and maintained so that there is no leakage of solvent when closed.

(e) Solvent transfer.

(1) Transfer of flammable solvents from containers shall be by means of a hose or pipe leading to the bottom of the tank being filled. Containers between which the transfer is being made shall be electrically bonded and grounded with a resistance of less than 25 ohms.

(2) Volatile solvents shall not be stored or transferred in uncovered vessels.

(f) Vapor phase degreasing.

(1) Freeboard. The level of the vapors shall be kept below the top edge of the tank by a distance equal to at least one-half the tank width or 36 inches, whichever is less.

(2) Heating.

(i) Gas. Where gas is used as fuel for heating, the combustion chamber shall be of tight construction, except for necessary combustion and flue openings. Mechanically ventilated flues shall be independent of the exhaust duct. Natural draft flues shall be provided with draft diverters. All flues shall be constructed of corrosion-resistant material.

(ii) Electric. Electric heating units shall be constructed of materials resistant to the tank contents and shall be constructed and installed so as to prevent hot spots.

(3) Thermostatic control. Every tank shall be provided with two thermostats, one of which shall be connected to control or shut off the source of heat when the contents reach a temperature not higher than 20 degrees Fahrenheit in excess of the boiling point of the solvent in its uncontaminated state and the other of which shall be located above the vapor zone and be adjusted to shut off the source of heat when the temperature in the zone of the thermostat is at the boiling point of the solvent.

(4) Condensers. Tanks shall be equipped with condensing or cooling surfaces consisting of pipes, coils, water jackets or any combination thereof located on at least two sides in the upper portion of the tank above the solvent liquid level. Water, refrigerant or other cooling media shall be circulated through the condenser whenever the tank is in operation.

(g) Operation.

(1) Where tanks are provided with loading hoists, the hoists shall be designed to raise and lower the work at a speed not greater than 11 feet per minute.

(2) All products after immersion in solvents shall be held in the vapor zone of the tank and shall not be withdrawn from the tank until the product reaches the vapor temperature as evidenced by the stopping of vapor condensation on the product.

(3) Loading racks shall be of metal or equally impervious material.

(4) The horizontal cross section area of product or rack shall not be greater than two-thirds of the horizontal cross section area of the tank.

(h) Welding and open flame work. No work involving welding, open flames or other sources of ignition shall be done at or about any equipment for open surface tank operations unless such equipment has first been thoroughly cleaned of all flammable or volatile solvents and their vapors or is protected by distance or by shielding against accidental ignition or heating from such work.

(i) Special precautions for cyanide.

(1) Where rinse, acid and cyanide tanks are so installed and used that any of them may be contaminated with cyanide or acid, such tanks shall be provided with local exhaust ventilation.

(2) Cyanide tanks shall not be provided with drains or overflows which will allow the tank contents to mix with liquid drained from other tanks either on the floor or in floor drains unless the cyanide drainage has been properly neutralized.

(3) Cyanide salts shall be stored in a locked enclosure and set above the level of any floor on which acid carboys are stored.

N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 12-2.4