D.C. Municipal Regulations (Last Updated: September 13, 2017) |
Title 20. ENVIRONMENT |
Chapter 20-7. AIR QUALITY - VOLATILE ORGANIC COMPOUNDS AND HAZARDOUS AIR POLLUTANTS |
Section 20-769. SOLVENT CLEANING – RECORDKEEPING AND MONITORING
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769.1The operator of a solvent cleaning machine subject to §§ 764 through 767 shall conduct monitoring and record keeping as follows:
(a)If a freeboard refrigeration device is used to comply with these standards, the owner or operator shall use a thermometer or thermocouple to measure the temperature at the center of the air blanket during the idling mode. Measurements and recordings shall be made weekly;
(b) If a superheated vapor system is used to comply with these standards, the owner or operator shall use a thermometer or thermocouple to measure the temperature at the center of the superheated solvent vapor zone while the solvent cleaning machine is in the idling mode. Measurements and recordings shall be made weekly;
(c)If a cover (working-mode, downtime-mode, or idling-mode cover) is used to comply with these standards, the owner or operator shall conduct a visual inspection to determine if the cover opens and closes properly, completely covers the cleaning machine openings when closed, and is free of cracks, holes, and other defects. Observations and recordings shall be made weekly;
(d) If dwell is used, the owner or operator shall determine the actual dwell time by measuring the period of time that parts are held within the freeboard area of the solvent cleaning machine after cleaning. Observations and recordings shall be made monthly;
(e) The owner or operator shall determine the hoist speed by measuring the time it takes for the hoist to travel a measured distance. The speed is equal to the distance in meters divided by the time in minutes (meters per minute). Measurements and recordings shall be made monthly;
(f) The owner or operator of a batch vapor or in-line solvent cleaning machine complying using reduced room draft, maintained by controlling room parameters including but not limited to redirecting fans, and closing doors and windows, shall conduct monitoring and record the results as follows:
(1)Initially measure the wind speed within six inches (6 in.) above the top of the freeboard area of the solvent cleaning machine in accordance with the following:
(A)Determine the direction of the wind current by slowly rotating a velometer or similar device until the maximum speed is located;
(B) Orient a velometer in the direction of the wind current at each of the four corners of the machine;
(C)Record the reading for each corner; and
(D)Average the values obtained at each corner and record the average wind speed;
(2)Record the room parameters established during the initial compliance test to achieve the reduced room draft;
(3)Quarterly monitor the wind speed in accordance with subparagraph (f)(1) of this section; and
(4)Weekly monitor the room parameters as specified in this section;
(g) If an enclosure, full or partial, is used to achieve reduced room draft, the owner or operator shall conduct an initial monitoring test and, thereafter, monthly monitoring tests of the wind speed within the enclosure by slowly rotating a velometer inside the entrance to the enclosure until the maximum speed is located and record the maximum wind speed. The owner or operator shall also conduct a monthly visual inspection of the enclosure to determine if it is free of cracks, holes, and other defects; and
(h)If a carbon adsorber is used to comply with these standards, the owner or operator shall measure and record the concentration of halogenated HAP solvent in the exhaust of the carbon adsorber weekly with a colorimetric detector tube;
(1)This test shall be conducted while the solvent cleaning machine is in the working mode and is venting to the carbon adsorber;
(2)The exhaust concentration shall be determined using a colorimetric detector tube designed to measure a concentration of one hundred parts per million (100 ppm) by volume of solvent in air to an accuracy of plus or minus twenty-five parts per million (25 ppm) by volume; and
(3)The concentration shall be determined through a sampling port for monitoring within the exhaust outlet that is easily accessible and located at least eight (8) stack or duct diameters downstream and two (2) stack or duct diameters upstream from any flow disturbance such as a bend, expansion, contraction, or outlet; downstream from no other inlet.