ENGINEERING CALCULATION SHEET AIR RESOURCES DIVISION

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1 Page 1 of 5 Date Application Received: September 30, 2002 Application #: FY PROJECT DESCRIPTION: FY is for a renewal application for 6 spray booths (FP-T-0060 expired on July 31, 2002). FACILITY DESCRIPTION: operates wood furniture manufacturing facility in Manchester, New Hampshire. The facility manufactures wood furniture from purchased veneer stock. The main operations at the facility are stain, seal and topcoat applications using HVLP and Airmix spray guns. The six spray booths are equipped with overspray filters. Other operations at the facility include cutting lumber, sanding, minor gluing, air drying, packaging and shipping. Potential emissions exceed major source threshold for HAP, VOC and the applicability limit for VOC RACT. The facility requests permit restrictions to stay below major source thresholds for HAP and VOC and to opt out of VOC RACT, Env-A (a) Applicability Criteria for the Coating of Wood Furniture, Burial Caskets and Gunstock. Therefore, the facility requires for the spray booths PROJECT DESCRIPTION: Renewal of SOP. SIGNIFICANT EMISSION UNITS: Emission Unit Unit Description (Manufacturer & Model #) Table 1-Significant Emission Units Install Date Permit Limits Stain Booth 1 & 2 Sealer Booth 1 & 2 Topcoat Booth 1 & 2 1. Total VOC emissions from all six spray booths shall be limited to less than 25 tpy for the facility to opt out of VOC RACT. 2. Total HAP emissions for any single HAP shall be limited to less than 10 tpy and for all HAPs combine to less than 25 tpy to opt out of 40 CFR Subpart JJ, NESHAP for Wood Furniture. Insignificant Emission Units: 3 Boilers (NG) rated at 1.9 mmbtu/hr each used for space heating EMISSION CALCULATIONS:

2 Page 2 of 5 Table2- Emissions Device VOCs Single HAP Total HAPs Hourly Emissions-Pounds per Hour Spray Booths (6) * 4.54 Potential Emissions-tpy Spray Booths (6) * 19.9 Facility-Wide Limits 1 <25 <10 <25 *Single HAP emissions refer to toluene emissions which has the highest emissions. Emission Rates: Coatings applied in ,692 lbs VOCs emitted in ,741 lbs Hourly VOC rate 31,741lbs/yr/2600hrs/yr=12.21 lb/hr Actual production hours-2600/yr Potential VOC lb/hr*8760 hr/yr=83028 lb/yr=53.5 tpy Solids applied in , =9,951 lbs Transfer Efficiency: Airmix-7guns 78% HVLP-12 guns 65% Filter Efficiency 99.84% Discussion: Oak Designs chose to use actual emissions for a dispersion modeling analysis. The air toxics impacts are very low so that even if production would increase the impacts still would fall below their corresponding AALs. The increase in production most likely would result in increase in hours of operation rather than production rate since there are natural bottle necks in this operation like drying time, preparation time and floor space. Assuming that emissions would increase to 25 tpy (facility limit enforced by permit) and the hours of operation would stay the same, (2600/yr) the emission rate for toluene (toluene has the highest emission rate for the facility) would increase from 2.43 lb/hr to 3.82 lb/hr resulting in the 24-hr impact of 374 ug/m 3 which would still be only 55.7% of the its AAL. MODELING: The facility was modeled to determine compliance with Env-A 1400 on November 7, 2000 for the temporary permit. All impacts for RTAPs based on actual emissions were below 50% of the corresponding AALs with the largest 1 The Facility has the potential to emit criteria pollutants at levels greater than major source thresholds. Facility-wide emission limits are set for the purpose of establishing this source as a synthetic minor source of air pollution. Such limits shall not be construed to allow this source to construct or install a new or modified source, area source or device except in the manner set forth in the New Hampshire Rules Governing the Control of Air Pollution and, specifically, Env-A 603.

3 Page 3 of 5 percentage of the AALs coming from toluene at 35.4% (24-hr). There was no changes in the process since the temporary permit was issued. The RTAPs impacts are as follows. Maximum Predicted Impacts for RTAPs@ 1 lb/hr Averaging Period Maximum Concentration (ug/m 3 ) 24-Hour 97.9 Annual 24.5 Procedures for Determining Compliance with Env-A 1400 for a New Coating: For a single coating containing the RTAP, the amount of coating used, in gallons per day, shall be limited according to the following equation: 24-hour Annual ( 24hrs / day) AAL24hr MG24 hr = ; and ug / m ( D)( WF ) 1lb / hr MG annual AALann = 24.5ug / m 1lb / hr ( 8760hrs / yr) 3 ( D)( WF ) Where: MG = The maximum number of gallons which may be used during any consecutive 24-hour or annual period for an individual RTAP; AAL = The 24-hour or annual AAL for each individual pollutant contained in Table , in µg/m 3 ; D = The density of the new coating in lb/gal; WF = The weight fraction of the specific RTAP contained in the coating normally obtained by dividing the weight percentage provided on the applicable MSDS by 100; 97.9 (µg/m 3 )/(lb/hr) = The maximum 24-hour modeled ambient impact for a unit emission rate using the SCREEN3 dispersion model; 24.5 (µg/m 3 )/(lb/hr) = The maximum annual modeled ambient impact for a unit emission rate using

4 Page 4 of 5 the SCREEN3 dispersion model. a. For two or more coatings applied during the applicable 24-hour and annual period containing the RTAP, the amounts of the coatings used shall be restricted by the following equation: 24-hour [G (1) * D (1) * WF (1) + G (2) * D (2) * WF (2) + + G (N) * D (N) * WF (N) ] * [97.9 (µg/m 3 ) / (lb/hr)]/24 hours per day) AAL 24hr Annual [G (1) * D (1) * WF (1) + G (2) * D (2) * WF (2) + + G (N) * D (N) * WF (N) ] * [24.5 (µg/m 3 ) / (lb/hr)]/8760 hours per year) AAL annual Where: N = The total number of different coatings applied over the applicable 24-hour period containing the RTAP; G(1), G(2), etc. are the number of gallons that may be used for each coating (coating No. 1, coating No. 2, etc.) applied over the applicable 24-hour period (gallons per day) containing the RTAP; D(1), D(2), etc. are the densities (lb/gal), as provided on the MSDS, of each coating (coating No. 1, coating No. 2, etc.), applied over the applicable 24-hour period, containing the RTAP; WF(1), WF(2), etc. are the weight fractions of the RTAP, normally obtained by dividing the weight percentages provided on the applicable MSDS by 100, of each coating (coating No. 1, coating No. 2, etc.) applied over the applicable 24-hour period; and 97.9 (µg/m3) / (lb/hr) = The maximum annual modeled ambient impact for a unit emission rate: 24.5 (µg/m3) / (lb/hr) = The maximum annual modeled ambient impact for a unit emission rate: STACK INFORMATION: Table 5-Stack Criteria Device Stack Height (Ft Above Ground) Stack Diameter (Ft) Stack Exit Area (Ft 2 ) Stack Velocity (Ft/min) Stack Flow Rate (ACFM) Spray Booths ,637 10,321 APPLICABLE REGULATIONS: NSPS N/A NESHAP N/A

5 Page 5 of 5 Title V N/A, Facility took limits to become synthetic minor. Env-A 300 AAQS Applicable Env-A 600 Statewide Permit System Applicable Env-A 700 Permit Fee System Applicable Env-A 800 Testing & Monitoring Procedures Applicable Env-A 900 Owner/Operator Obligations Applicable Env-A 1200 Prevention, Abatement, and Control of Stationary Source Air Pollution Applicable to Env-A , but the facility took limits to opt out of VOC RACT. Env-A Regulated Toxic Air Pollutants Applicable Env-A 2100 Process, Manufacturing and Service-Based Industries Applicable (Opacity and PM standards) SUMMARY AND CONCLUSIONS: Issue SPO permit.