1. (1) Use of certain flammable liquids. The use of flammable liquids for paint removal, cleaning or any other process in which they are unprotected and exposed shall be restricted to areas provided with mechanical ventilation creating an air movement of at least 100 feet per minute over the surface of the work while the work is being carried on. The use of benzene for such operations is prohibited. Any solvent used shall contain not more than 3 percent benzene as an impurity. Flammable liquids shall not be used to clean walls, ceilings or floors in a workroom.

2. (2) Transfer of flammable liquids. The transfer of flammable liquids shall be by means of a hose or pipe leading to the bottom of the vessel being filled, except for the filling of approved safety cans. When transferring such liquids from one metal container to any other metal container, the two containers shall be bonded together electrically and be properly grounded.

   Exception:

   This paragraph does not apply to the filling of motor vehicle and industrial equipment fuel tanks.

3. (3) Mixing and thinning of flammable liquids. The mixing and thinning indoors of flammable liquids in unit quantities greater than 55 gallons shall be done only in a mixing or spraying room and in such manner and under such ventilation as will effect compliance with this Part (rule). Lesser quantities shall be mixed or thinned indoors only in such a room or within a hood, booth or working area provided with ventilation as specified in section 18.20 of Industrial Code Part (Rule No.) 18.

   Exception:

   Quantities of five gallons or less may be mixed or thinned when natural ventilation will reduce the vapor concentrations to the limits as specified in Table I of this Part (rule) within five minutes.

4. (4) Coating removal by use of solvents. Such a process shall be provided with adequate exhaust ventilation while the removal of residue, paint or other material is being performed. The rate of ventilation shall be that specified in Industrial Code Part (Rule No.) 18.

   Note:

   The use of benzene or carbon tetrachloride for such an operation is prohibited.

5. (5) Cleaning solvents. Flammable liquids used for cleaning permanent surfaces other than floors in a working space shall have a flash point above 100 degrees Fahrenheit. The use of benzene for this operation is prohibited. No flammable liquids shall be used to clean floors.

6. (6) Tanks, troughs and mechanical application. Note:

   1. (i) Enclosed operations. Enclosed operations involving the use of flammable liquids and any subsequent drying operations shall be mechanically ventilated to maintain the concentration of vapors within the enclosures below 25 percent of the lower explosive level. Necessary work openings of such enclosures shall have inward air flows maintained by mechanical ventilation. As an alternative method, enclosed processes may be operated in an inert atmosphere. Where an inert atmosphere is used for an enclosed operation, adequate provision shall be made to insure that sufficient oxygen is available in the areas surrounding such enclosed operation. Any escape of the inert atmosphere to areas outside the enclosure shall not accumulate and create dangerous air contaminants.

   2. (ii) Fire protection. Tanks and troughs containing flammable liquids shall be provided with heat-actuated automatically closing covers arranged so as not to interfere with exhaust ventilation. Where operations in such tanks and troughs are performed automatically the tanks and troughs shall be provided with approved fire extinguishing systems.

      Note:

      For additional requirements concerning fire protection see paragraph 12-1.8(c)(1) of this Part (rule).

   3. (iii) Installation of tanks. Tanks shall be arranged to prevent accidental tipping.

   4. (iv) Heating of liquids. Devices used for heating flammable liquids shall be provided with an automatic temperature regulation device so arranged that the source of heat shall be automatically shut off when the temperature of the liquid rises above the normal operating temperature.

      (b) Storage of flammable liquids.

7. (1) Enclosure of storage rooms. The floor surfaces of rooms used for the storage of flammable liquids shall be of incombustible material and shall be waterproof. The room enclosure shall be of construction having the following minimum fire-resistive rating: Note:

   Walls	1 hour
   Doors	¾ hour
   Windows	¾ hour
   Ceiling (if space above is occupied)	1 hour
   Floor	1 hour

   Note:

   For requirements concerning fire-resistive construction see Industrial Code Part (Rule No.) 7.

8. (2) Location of storage rooms. Storage rooms for flammable liquids shall be located at or above grade and an exterior wall of the building shall form at least one wall of the room. No opening in any storage room shall be located within 15 feet of any stairway, elevator shaft or building exit.

9. (3) Floor drainage and door sills.

   1. (i) Floors of storage rooms containing flammable liquids shall be constructed so as to confine any spillage of flammable liquids. Solid floors shall be pitched at least one inch in 36 inches from the walls and entrances toward a drain which shall be provided to direct the liquid to a safe location outside the plant, such as a sump, tank or similar collecting basin. Every drain shall be equipped with a trap which shall be kept full of a suitable liquid and so maintained as to prevent back flow of flammable vapors. The drainage system from any room used for the storage of flammable liquids shall be isolated from the plant drainage system.
   2. (ii) Sills or ramps of incombustible material at least three inches in height shall be provided at every door leading to a storage room. Alternatively, six inch deep by six inch wide gutters covered with substantial open gratings and leading to drains shall be provided at such passageways. Such gutters shall extend across the full width of the openings within the storage rooms.

10. (4) Limitation of quantities. No more than one day's supply or 220 gallons of flammable liquid, whichever is less, shall be kept in a workroom. Such supply, unless kept in closed drums or in original sealed containers not to exceed five gallons capacity, or in approved safety cans, shall be kept in cabinets as follows:

    1. (i) Cabinets for storing quantities of flammable liquid not exceeding 110 gallons shall be of at least incombustible single wall construction and shall be vented to the outer air.
    2. (ii) Cabinets for storing quantities of flammable liquid of more than 110 gallons but less than 220 gallons shall be of incombustible double wall construction with an air space of at least one and one-half inches or metal-covered wood construction throughout and shall be vented to the outer air at top and bottom.
    3. (iii) Quantities exceeding 220 gallons shall be kept in a storage room as specified in paragraphs (1) through (3) of this subdivision. Doors to storage cabinets shall be kept closed and latched.

11. (5) Containers. Containers used for flammable or toxic liquids, whether or not they contain such material, shall be kept tightly covered when not in use or when being moved about with the exception of safety cans of any size and glass or plastic containers which are one quart or less in size (volume).

    (c) Other equipment requirements.

12. (1) Fire protection equipment. Note:

    1. (i) Automatic sprinklers. Automatic sprinkler systems with sufficient heads or outlets shall be provided in all working areas of buildings two stories or more in height where flammable liquids are used or stored.

       Note:

       For sprinkler system requirements see Industrial Code Part (Rule No.) 20.

    2. (ii) Automatic extinguishers. Dip tanks, drain boards, drip pans and drip troughs involving the use of flammable liquids shall be provided with approved automatic fire extinguishers except for the following:

       1. (a) Those used in electrostatic finishing.
       2. (b) Hand dipping tanks which with their associated drain boards, drip pans and drip troughs have a vapor surface area not greater than 16 square feet.
    3. (iii) Hand extinguishers. There shall be provided adjacent to the inside or outside of each required exit from the room in which flammable liquids are being used or stored at least one hand fire extinguisher approved for the control of flammable liquid fires. Extinguishers containing carbon tetrachloride, methyl bromide or other toxic material are prohibited for this usage. In addition, there shall be at least one approved extinguisher for each 2500 square feet of floor area so located that a person shall not have to travel more than 50 feet to reach the nearest extinguisher. Extinguishers shall be easily accessible and protected from damage.

13. (2) Electrical equipment. Exception:

    1. (i) Wiring and equipment. All electric wiring and electrical equipment shall be of good quality and be properly installed. Wiring within 10 feet of a working area or within a storage room shall be installed in sealed rigid metal conduit with explosion-proof fittings.

       Exception:

       Operations not involving flammable solvents.

    2. (ii) Lighting. Artificial lighting shall be by electricity. Lamps within areas where flammable liquids may be used or stored or where flammable vapors may be present shall be of the totally enclosed type and shall be protected against breakage either by location or by lamp guards. Lamp sockets shall be non-metallic shells and of the switchless type.
    3. (iii) Control equipment. Switches and other control devices, unless explosion-proof, shall be located at least 10 feet from the working area and outside of storage rooms.
    4. (iv) Flexible electrical cords and portable lights. Flexible electrical cords used in any area where flammable liquids are being used or stored or where flammable air contaminants may be present shall be of the three conductor, extra-heavy service type manufactured for the purpose and shall be fully insulated and grounded. All connections shall be explosion-proof. Portable lights used in such areas shall be shielded against breakage.

    5. (v) Other equipment. Exception:

       1. (a) All electrical equipment located in a storage room or the interior of coating hoods or their exhaust ducts shall be explosion-proof.

          Exception:

          Air mover motors installed in compliance with subdivision (d), section 18.11 of Industrial Code Part (Rule No.) 18.

       2. (b) Systems designed to salvage deposits by collecting them in flammable solvent shall have the controls so arranged that the solvent pump cannot operate unless the ventilating fan is operating.
    6. (vi) Grounding of equipment. All mechanical equipment used for the application of flammable liquids and all booths, hoods, tanks, troughs, conveyors, fans, motor housings and all belts within a working area shall be grounded.
14. (3) Heating. Units used for comfort heating of any space to which this Part (rule) applies in which flammable liquids are used, handled or stored shall be confined to the use of low-pressure steam or hot water or indirect forced warm air. Direct warm air heating systems may be used subject to approval by the board. Heating units shall be kept free of deposits of flammable compounds.
15. (4) Ventilation. Rooms used for the storage of flammable liquids shall be provided with a minimum rate of ventilation of five cubic feet per minute per square foot of gross floor area and the ventilation shall be maintained during transfer of flammable liquids from one container to another. Where mixing and thinning operations are performed, the rate of ventilation shall conform to the requirements of section 18.20 of Industrial Code Part (Rule No.) 18.

16. (5) Protection of adjacent occupancies.

    1. (i) Wall or ceiling construction. No employer shall suffer or permit flammable liquids to be used or dispensed in any room above or below or adjoining one in which there is an employee occupancy unless:

       1. (a) the room is part of a building which is a fireproof building or a fire-resisting building complying with the provisions of Industrial Code Part (Rule No.) 7, or
       2. (b) the walls and ceiling of the room within 20 feet horizontally of the working area are so constructed as to have a fire-resistance rating of at least one hour in accordance with Industrial Code Part (Rule No.) 7 and, if there be an employee occupancy below such room, the floor of the room within such distance is of incombustible material and is waterproof, or
       3. (c) such room is equipped with automatic sprinkler protection conforming to the provisions of Industrial Code Part (Rule No.) 20.
    2. (ii) Wall openings. Wall openings in every room in which flammable liquids are used, handled or stored shall be provided with approved three-quarter hour self-closing fire doors or with approved three-quarter hour fire windows. No such room shall have any window openings beneath or within 10 feet horizontally of any fire escape or required exterior stairway.

(a) Use of flammable liquids.