5. Class IV solvents are liquids classified as nonflammable.
3. Type III-A—systems using Class IIIA solvents.
4. Type III-B—systems using Class IIIB solvents.
|Q = 100 × ALD||(Equation 21-1)|
|Q||=||flow rate exhausted through the hood, cubic feet per minute (m3/s).|
|ALD||=||area of the loading door, square feet (m2).|
1. Only Class II or III liquids shall be used.
2. The total amount of solvent used in such open containers shall not exceed 3 gallons (11 L).
3. Scrubbing tubs shall be secured to the floor.
4. Scrubbing tubs shall be provided with permanent 11/2-inch (38 mm) drains. Such drain shall be provided with a trap and shall be connected to an approved container.
1. An automatic sprinkler system shall not be required in Type III-A dry cleaning plants where the aggregate quantity of Class III-A solvent in dry cleaning machines and storage does not exceed 330 gallons (1250 L) and dry cleaning machines are equipped with a feature that will accomplish any one of the following:
1.1. Prevent oxygen concentrations from reaching 8 percent or more by volume.
1.2. Keep the temperature of the solvent at least 30°F (16.7°C) below the flash point.
1.3. Maintain the solvent vapor concentration at a level lower than 25 percent of the lower explosive limit (LEL).
1.4. Utilize equipment approved for use in Class I, Division 2 hazardous locations in accordance with NFPA 70.
2. An automatic sprinkler system shall not be required in Type III-B dry cleaning plants where the aggregate quantity of Class III-B solvent in dry cleaning machines and storage does not exceed 3,300 gallons (12 490 L).