Plating process emissions calculations

This method may be used to develop an editable spreadsheet containing detailed emissions calculations for each plating process at your facility. Each step in your calculation(s) needs to be clear and easy to follow.

Include the following information with your calculations:

  • AQ Facility ID No. – Include your Air Quality (AQ) facility Identification Number (ID No.). This is the first eight digits of the permit number for all permits issued under the operating permit program. If your facility has never been issued a permit under this program, do not include at this time.
  • AQ File No. – Include your AQ File Number, if known. This number can be found in the “cc” section of correspondence from the MPCA. If you do not know this, or can’t find it, do not include it at this time.
  • Facility name – Include your facility name.
  • Emission unit ID(s) – Include the identification number of each emission unit. Obtain this number from your Form GI-05B, or the appropriate form related to the permit you are applying for, or your existing permit. If you are applying for a registration permit Option D, just provide a description of the emission unit.
  • Stack/Vent designation number(s) – Include the designation number of the stack(s) or vent(s) through which the unit will exhaust into the atmosphere. Obtain these numbers from Form GI-04, or the appropriate form related to the permit you are applying for, or your existing permit. If you are applying for a registration permit Option D, just provide a description of the control equipment.
  • Control equipment Include a description of the type of control equipment. Use either the identifying number from Form GI-05A, or the appropriate form related to the permit you are applying for, or your existing permit. If none, indicate no control equipment. If you are applying for a registration permit Option D, just provide a description of the control equipment.
  • Type of plating Indicate the type of plating:  decorative chrome, hard chrome, chromic acid or other (provide description).
  • Operating parameters – Include the capacity in total amps for an electroplating operation, or the capacity in total square foot per hour capacity for an anodizing operation.
  • Solutions or chemicals used List the pollutant-emitting solutions and chemicals that are used in this plating process.
  • Source of emission factors – Indicate the sources of your emission factors. Possible sources include those listed on the Emissions Calculations page and those described in Minn. R. 7005.0100, subp. 10. If the emission factor is from AP-42, cite the exact section or table used. If emission factor is from some other source, attach a photocopy of the information used, or provide an exact internet address, so the information can be verified.
  • Formula/Equation – The formula and/or equation needs to be available in each spreadsheet cell for which there is a calculation (for example, Steps 3, 4, 6, 7, and 8 below.)
  • Operating limitations – Describe in detail any permit limits you plan to take to restrict your potential-to-emit (fuel type and/or usage, hours of operation, bottlenecks, etc. - see Proposing Synthetic Minor Permit Limits). Attach additional spreadsheets or other information, if needed. Describe the limiting factors, cite any rules that apply (e.g., Standards of Performance for Stationary Sources (NSPS, 40 CFR part pt. 60), Best Available Control Technology [BACT]). The associated limit must be used to calculate your potential-to-emit after permit limits in Step 8. If you used vendor certification or stack test data to limit your potential-to-emit, the factor you used will become your permit limit. Include all proposed limits on Form CD-01, and anywhere else as instructed in the application forms.

Emissions Calculation Instructions

Follow these steps for calculating your emissions for each plating operation at your facility. Generally, each column of your spreadsheet will correlate to each step indicated below. Additional columns can and should be included in the spreadsheet to indicate additional steps or information specific to your operation.

Step 1. Pollutant 

Include each of the following pollutants that your plating operation emits.

  • PM = particulate matter
  • PM10 = particulate matter smaller than 10 microns in aerodynamic diameter
  • PM2.5 = particulate matter smaller than 2.5 microns in aerodynamic diameter
  • HAPs = hazardous air pollutants – each individual hazardous air pollutant. See EPA's Web site for more information.
  • Total HAPs = All HAPs added together

Step 2. Emission factor

Include the emission factor for the plating operation. Remember to use uncontrolled emission factors, and include the applicable units. Include the source of the emission factors used. Attach a separate sheet, if necessary.

Step 3. Emission rate

Calculate the emission rate in pounds per hour by using one of the following methods.


For emission factors in:

Use this equation:

Pounds per amp-hour  (lb/amp-hr)

Emission rate (lb/hr) = Emission factor (lb/amp-hr)  x  Electroplating capacity (amps)

Pounds per square foot-hour(lb/hr-ft2)

Emission rate (lb/hr) = Emission factor (lb/hr-ft2)  x  Anodizing capacity (square feet)

Step 4. Maximum uncontrolled emissions

Calculate the Maximum uncontrolled emissions by using the following method:

  • Maximum uncontrolled emissions (tons/yr) = Emission rate (lb/hr) x 8760 (hrs/yr) x 0.0005 (tons/lb)

Step 5. Pollution control efficiency

Indicate the pollution control efficiency. The pollution control efficiency is the product of the capture efficiency and the destruction/collection efficiency indicated on Form GI-05A (or other similar form, depending on the type of permit you are applying for), or in your existing permit. Document this number here, and if you are applying for a new individual permit or an amendment to an existing individual permit, remember to include on Form CD-05 a plan to demonstrate and maintain the destruction/collection efficiency. The efficiency should be expressed for each pollutant. If there is no control for a particular pollutant, indicate “zero” as the control efficiency.

Step 6. Maximum controlled emission rate [lb/hr]

This is the maximum controlled emissions rate in lb/hr required in the first column of item 3e on Form GI-07. Calculate the controlled emissions by using the following method:

  • Max. controlled emission rate [lb/hr] = Emission rate (lb/hr) x (100 – Pollution control efficiency) ÷ 100

Step 7. Maximum controlled emissions

Calculate the Maximum Controlled Emissions in tons/year. Use this method for the calculation:

  • Max. controlled emissions [tons/year] = Maximum Controlled Emissions (tons/year) x (100 – Pollution control efficiency) ÷ 100.

Step 8. Limited controlled emissions

(Skip this item if you are working on calculations for a Registration Permit Option D.)

The limited controlled emissions are calculated by taking into account all limitations on operation of the source you are proposing to comply with in this application. These limitations include limits on hours of operation, on the amount of material used. You start the calculation of limited controlled emissions by repeating the calculation of emission rate [starting with Step 3] but taking into account the limits you propose. This is the limited controlled emissions in tons per year in the right column of item 3e on Form GI-07.

If an emission unit is subject to an emission limitation specified in 40 CFR pt. 60, 40 CFR pt. 61, 40 CFR pt. 63 or Minn. R. ch. 7011, you must show this requirement in the calculation of limited controlled emissions and take this into account in calculating the limited controlled emissions. If you choose to propose to comply with more a stringent limit, you should state this clearly and show the resulting allowed emissions in this calculation.

Step 9.   Actual emissions

If this is an existing unit or operation and historical records exist, calculate actual emissions using the average of the previous two calendar years of usage data (last 12 months if doing calculations for Registration Permit Option D), or average the previous two emission inventory reports if an inventory was submitted. Report actual emissions in tons/year.

To calculate actual emissions using the above equations, substitute actual operating parameters and/or hours per year operated for the maximum capacities.

Step 10. Operating limitations

(Skip this item if you are working on calculations for a Registration Permit Option D.)

Describe any permit limits you plan to take to restrict your PTE (raw material usage, hours of operation, etc.). Include additional sheets in the spreadsheet, if necessary. Describe the limiting factors and cite any rules that apply (e.g., Minn. Rules, Best Available Control Technology [BACT]). The associated limits must be used to calculate your Limited Controlled Emissions. If you used vendor certification or stack test data to limit your emissions, that factor will become a permit limit. Include all proposed limits on Form CD-01.