(a) All terms used in this subpart, not defined below, are given the same meaning as in the Act or in subpart A of this part.

Emission control device means any solvent recovery or solvent destruction device used to control volatile organic compounds (VOC) emissions from flexible vinyl and urethane rotogravure printing lines.

Emission control system means the combination of an emission control device and a vapor capture system for the purpose of reducing VOC emissions from flexible vinyl and urethane rotogravure printing lines.

Flexible vinyl and urethane products mean those products, except for resilient floor coverings (1977 Standard Industry Code 3996) and flexible packaging, that are more than 50 micrometers (0.002 inches) thick, and that consist of or contain a vinyl or urethane sheet or a vinyl or urethane coated web.

Gravure cylinder means a plated cylinder with a printing image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's surface to hold ink when continuously revolved through a fountain of ink.

Ink means any mixture of ink, coating solids, organic solvents including dilution solvent, and water that is applied to the web of flexible vinyl or urethane on a rotogravure printing line.

Ink solids means the solids content of an ink as determined by Method 24, ink manufacturer's formulation data, or plant blending records.

Inventory system means a method of physically accounting for the quantity of ink, solvent, and solids used at one or more affected facilities during a time period. The system is based on plant purchase or inventory records.

Plant blending records means those records which document the weight fraction of organic solvents and solids used in the formulation or preparation of inks at the vinyl or urethane printing plant where they are used.

Rotogravure print station means any device designed to print or coat inks on one side of a continuous web or substrate using the intaglio printing process with a gravure cylinder.

Rotogravure printing line means any number of rotogravure print stations and associated dryers capable of printing or coating simultaneously on the same continuous vinyl or urethane web or substrate, which is fed from a continuous roll.

Vapor capture system means any device or combination of devices designed to contain, collect, and route organic solvent vapors emitted from the flexible vinyl or urethane rotogravure printing line.

(b) All symbols used in this subpart not defined below are given the same meaning as in the Act or in subpart A of this part.

a = the gas stream vents exiting the emission control device. bthe gas stream vents entering the emission control device. fthe gas stream vents which are not directed to an emission control device. Caj = the concentration of VOC in each gas stream (j) for the time period exiting the emission control device, in parts per million by volume. Cbi = the concentration of VOC in each gas stream (i) for the time period entering the emission control device, in parts per million by volume. Cfk = the concentration of VOC in each gas stream (k) for the time period which is not directed to an emission control device, in parts per million by volume. Gthe weighted average mass of VOC per mass of ink solids applied, in kilograms per kilogram. Mci = the total mass of each ink (i) applied in the time period as determined from plant records, in kilograms. Mdj = the total mass of each dilution solvent (j) added at the print line in the time period determined from plant records, in kilograms. Qaj = the volumetric flow rate of each effluent gas stream (j) exiting the emission control device, in standard cubic meters per hour. Qbi = the volumetric flow rate of each effluent gas stream (i) entering the emission control device, in standard cubic meters per hour. Qfk = the volumetric flow rate of each effluent gas stream (k) not directed to an emission control device, in standard cubic meters per hour. Ethe VOC emission reduction efficiency (as a fraction) of the emission control device during performance testing. Fthe VOC emission capture efficiency (as a fraction) of the vapor capture system during performance testing. Woi = the weight fraction of VOC in each ink (i) used in the time period as determined from Method 24, manufacturer's formulation data, or plant blending records, in kilograms per kilogram. Wsi”means the weight fraction of solids in each ink (i) used in the time period as determined from Method 24, manufacturer's formulation data, or plant blending records, in kilograms per kilogram. Woj = the weight fraction of VOC in each dilution solvent (j) added at the print line in the time period determined from Method 24, manufacturer's formulation data, or plant blending records, in kilograms per kilogram. [49 FR 26892, June 29, 1984; 49 FR 32848, Aug. 17, 1984, as amended at 65 FR 61768, Oct. 17, 2000]