EAi is the average halogenated HAP solvent emissions over the preceding 3 monthly reporting periods, kilograms of solvent per square meter of solvent/air interface area per month (pounds of solvent per square foot of solvent/air interface area per month)

EAn is the average halogenated HAP solvent emissions over the preceding 3 monthly reporting periods, kilograms of solvent per month (pounds of solvent per month)

Eij is the halogenated HAP solvent emissions for each month (j) for the most recent 3 monthly reporting periods, kilograms of solvent per square meter of solvent/air interface area per month (pounds of solvent per square foot of solvent/air interface area per month)

Enj is the halogenated HAP solvent emissions for each month (j) for the most recent 3 monthly reporting periods, kilograms of solvent per month (pounds of solvent per month)

j=1 is the most recent monthly reporting period

j=2 is the monthly reporting period immediately prior to j=1

j=3 is the monthly reporting period immediately prior to j=2

NR 469.09(4)(4) Each owner or operator of a batch vapor or in-line solvent cleaning machine using dwell to comply with ss. NR 469.04 to 469.07 shall determine the appropriate dwell time for each part or parts basket using the procedure specified in pars. (a) and (b).

NR 469.09(4)(a)(a) Determine the amount of time for the part or parts basket to cease dripping once placed in the vapor zone. The part or parts basket used for this determination shall be at room temperature before being placed in the vapor zone.

NR 469.09(4)(b)(b) The proper dwell time for parts to remain in the freeboard area above the vapor zone is no less than 35% of the time determined in par. (a).

NR 469.09(5)(5) An owner or operator of a source shall determine the source’s potential to emit from all solvent cleaning machines, using the procedures described in pars. (a) to (c).

NR 469.09(5)(a)(a) Determine the potential to emit for each individual solvent cleaning machine using equation 6.

PTEi is the potential to emit for solvent cleaning machine i, kilograms of solvent per year (pounds of solvent per year)

Hi is hours of operation for solvent cleaning machine i (hours per year)

= 8760 hours per year, unless otherwise restricted by a federally enforceable requirement

Wi is the working mode uncontrolled emission rate for solvent cleaning machine i, kilograms per square meter per hour (pounds per square foot per hour)

= 1.95 kilograms per square meter per hour (0.40 pounds per square foot per hour) for batch vapor and cold cleaning machines

= 1.12 kilograms per square meter per hour (0.23 pounds per square foot per hour) for in-line cleaning machines

SAIi is the solvent/air interface area of solvent cleaning machine i, square meters, (square feet). Section NR 469.02 (38) defines the solvent/air interface area for those machines that have a solvent/air interface. Solvent cleaning machines that do not have a solvent/air interface shall calculate a solvent/air interface area using the procedure in par. (b).

NR 469.09(5)(b)(b) Solvent cleaning machines that do not have a solvent/air interface shall calculate a solvent/air interface area using equation 7.

SAI is the solvent/air interface area (square meters)

Vol is the cleaning capacity of the solvent cleaning machine (cubic meters)

NR 469.09 NoteNote: Equation 7 requires the use of metric units. Multiply cubic feet by 0.02832 to obtain cubic meters. Multiply square meters by 10.764 to obtain square feet.

NR 469.09(5)(c)(c) Sum the PTEi for all solvent cleaning machines to obtain the total potential to emit for solvent cleaning machines at the facility.