NR 440.74(2)(b)1.1. “Ak” means the area of each natural draft opening (k) in a total enclosure, in square meters.

NR 440.74(2)(b)2.2. “Caj” means the concentration of VOC in each gas stream (j) exiting the emission control device, in parts per million by volume.

NR 440.74(2)(b)3.3. “Cbi” means the concentration of VOC in each gas stream (i) entering the emission control device, in parts per million by volume.

NR 440.74(2)(b)4.4. “Cdi” means the concentration of VOC in each gas stream (i) entering the emission control device from the affected coating operation, in parts per million by volume.

NR 440.74(2)(b)5.5. “Cfk” means the concentration of VOC in each uncontrolled gas stream (k) emitted directly to the atmosphere from the affected coating operation, in parts per million by volume.

NR 440.74(2)(b)6.6. “Cgv” means the concentration of VOC in the gas stream entering each individual carbon absorber vessel (v), in parts per million by volume. For purposes of calculating the efficiency of the individual absorber vessel, Cgv may be measured in the carbon adsorption system’s common inlet duct prior to the branching of individual inlet ducts.

NR 440.74(2)(b)7.7. “Chv” means the concentration of VOC in the gas stream exiting each individual carbon absorber vessel (v), in parts per million by volume.

NR 440.74(2)(b)8.8. “E” means the control device efficiency achieved for the duration of the emission test, expressed as a fraction.

NR 440.74(2)(b)9.9. “F” means the VOC emission capture efficiency of the vapor capture system achieved for the duration of the emission test, expressed as a fraction.

NR 440.74(2)(b)10.10. “FV” means the average inward face velocity across all natural draft openings in a total enclosure, in meters per hour.

NR 440.74(2)(b)11.11. “Hv” means the individual carbon absorber vessel (v) efficiency achieved for the duration of the emission test, expressed as a fraction.

NR 440.74(2)(b)12.12. “Hsys” means the carbon adsorption system efficiency calculated when each absorber vessel has an individual exhaust stack.

NR 440.74(2)(b)13.13. “Mci” means the total mass (kg) of each coating (i) applied to the substrate at an affected coating operation during a nominal 1-month period as determined from facility records.

NR 440.74(2)(b)14.14. “Mr” means the total mass (kg) of VOC recovered for a nominal 1-month period.

NR 440.74(2)(b)15.15. “Qaj” means the volumetric flow rate of each gas stream (i) exiting the emission control device, in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration.

NR 440.74(2)(b)16.16. “Qbi” means the volumetric flow rate of each gas stream (i) entering the emission control device, in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration.

NR 440.74(2)(b)17.17. “Qdi” means the volumetric flow rate of each gas stream (i) entering the emission control device from the affected coating operation, in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration.

NR 440.74(2)(b)18.18. “Qfk” means the volumetric flow rate of each uncontrolled gas stream (k) emitted directly to the atmosphere from the affected coating operation, in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration.

NR 440.74(2)(b)19.19. “Qgv” means the volumetric flow rate of the gas stream entering each individual carbon adsorber vessel (v), in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration. For purposes of calculating the efficiency of the individual adsorber vessel, the value of Qgv can be assumed to equal the value of Qgv measured for that adsorber vessel.

NR 440.74(2)(b)20.20. “Qhv” means the volumetric flow rate of the gas stream exiting each individual carbon adsorber vessel (v), in dry standard cubic meters per hour when Method 18 or 25 is used to measure VOC concentration or in standard cubic meters per hour (wet basis) when Method 25A is used to measure VOC concentration.

NR 440.74(2)(b)21.21. “Qin i” means the volumetric flow rate of each gas stream (i) entering the total enclosure through a forced makeup air duct, in standard cubic meters per hour (wet basis).

NR 440.74(2)(b)22.22. “Qout j” means the volumetric flow rate of each gas stream (j) exiting the total enclosure through an exhaust duct or hood, in standard cubic meters per hour (wet basis).

NR 440.74(2)(b)23.23. “R” means the overall VOC emission reduction achieved for the duration of the emission test, expressed as a fraction.

NR 440.74(2)(b)24.24. “RSi” means the total mass (kg) of VOC retained on the coated substrate after oven drying or contained in waste coating for a given combination of coating and substrate.

NR 440.74(2)(b)25.25. “Woi” means the weight fraction of VOC in each coating (i) applied at an affected coating operation during a nominal 1-month period as determined by Method 24.

NR 440.74(2)(c)(c) Tables 1A and 1B present a cross reference of the affected facility status and the relevant subsections of the regulation.