APPENDIX III 

TEST METHOD FORMULAS AND NOMENCLATURE 
[last updated February 13, 2009] 

GEL Engineering, LLC 

A Member of The GEL Group, Inc.

TEST METHODS FORMULAS FOR STACK TESTING

INDEX 

page 

1. AREAS 2 

2. TEMPERATURE CONVERSIONS 2 

3. VOLUME OF AIR COLLECTED 3 

4. MOISTURE DETERMINATION 3 

5. MOLECULAR WEIGHT OF STACK GAS 3 

6. FLOW DETERMINATIONS 4 

7. ISOKINETICS DETERMINATION 5 

8. POLLUTANT DETERMINATIONS 5 

9. POLLUTANT CORRECTIONS 7

10. EFFICIENCY EQUATIONS 8 

11. METHOD 8 EQUATIONS 8 

12. NOMINAL NOZZLE SIZE 9 

13. F-FACTOR EQUATIONS 9 

14. CYCLONIC FLOW 11 

15. METHOD 5 POST TEST CALIBRATION 11 

16. WET BULB/DRY BULB 12 

17. VOLUME PER POINT (ISOKINETIC TESTING) 12 

 

18. INSTRUMENT TESTING 13 

19. HEAT INPUT 13 

20. CONVERSION FACTORS 14 

21. CONSTANTS 15 

22. NOMENCLATURE 16 
Page 2 

1. AREAS 

1.1 Area of Stack, Square feet (Round Stack)

As = 

Ds(width )

2 π

4

⎛

⎝ 

⎜ ⎞ 

⎠ 

ft2

144 in2

⎛

⎝ 

⎜ ⎞

⎠

1.2 Area of Stack, Square feet (Square Stack)

As = D( ) s(width ) ( ) Ds(depth )

ft2

144 in2

⎛

⎝ 

⎜ ⎞ 

⎠ 

1.3 Area of Nozzle, Square feet

An = 

Dn

2

π

4

⎛

⎝ 

⎜ ⎞ 

⎠ 

ft2

144 in2

⎛

⎝ 

⎜ ⎞

⎠

2. TEMPERATURE CONVERSIONS 

2.1 Temperature, Degrees Celsius—> Degrees Fahrenheit

 

To

F= To

( )C ( ) 9/ 5 + 32

2.2 Dry Gas Meter Temperature, Degrees Fahrenheit—>Degrees Rankin

 

Tmo

R= TmoF + 460

2.3 Stack Temperature, Degrees Fahrenheit—> Degrees Rankin

 

Ts

o

R= Ts

o

F + 460
Page 3 

3. VOLUME OF AIR COLLECTED

3.1 Volume of Dry Gas Sample, Corrected to Standard Conditions (cubic feet)

Vm(std) = V( ) m ( ) Y

Tstd

Tm°R

⎛ 

⎝ ⎞ ⎠ 

Pbar +

ΔH

13.6

⎛

⎝ ⎞ ⎠ 

Pstd

3.2 Volume of Dry Gas Sample, Corrected to Standard Conditions (liters)

Vm(std) = ( ) Vm ( ) Y ( ) Pbar ( ) Tstd

( ) Tm°R ( ) Pstd

4. MOISTURE DETERMINATION

4.1 Volume of Water Vapor Condensed in Impingers, Corrected to

Standard Conditions

Vwc(std) = V( )lc ( ) 0.04707

4.2 Volume of Water Vapor Collected in Silica Gel, Corrected to

Standard Conditions

Vwsg(std) = V( ) wsg ( ) 0.04715

4.3 Water Vapor in the Stack Gas, Proportion by Volume

Bws = 

Vwc(std) + Vwsg(std)

Vwc(std) + Vwsg(std) +Vm(std)

4.4 Dry Mole Fraction of Flue Gas

Mfd =1-Bws

5. MOLECULAR WEIGHT OF STACK GAS 

5.1 Nitrogen Content of Stack Gas, Percent

%N2dry = 100 - %CO2dry - %O2dry - %COdry
Page 4 

5.2 Dry Molecular Weight of the Stack Gas

Md = 0.44 %CO ( 2dry) + 0.32 %O ( 2 dry) + 0.28 %N ( 2dry + %COdry)

5.3 Wet Molecular Weight of the Stack Gas

Ms = M( )d (Mfd) + 18 B( ) ws

5.4 Sample Gas Density, pounds per cubic foot

Ps(sgd) = ( ) Md ( ) Mfd + ( ) 18 ( ) 1 − Mfd

385.3

5.5 Total Weight of Gas Sampled, pound

Wsg = ( ) Vm(std) + Vwc(std) + Vwsg(std) (Ps(std))

5.6 Excess Air, percent

%EA = %O2dry - 0.5 ( )(%COdry)

( ) 0.264 ( ) %N2 dry −( ) %O2dry − ( ) 0.5 ( ) %COdry

⎛

⎝ 

⎜ ⎞ 

⎠ 

⎟ 100

6. FLOW DETERMINATIONS 

6.1 Absolute Stack Gas Pressure

Ps = Pbar + 

Pg

13.6

6.2 Average Stack Gas Velocity, feet per second

Vs = K( )p ( ) Cp ( ) ΔP

Ts°R

( ) Ps ( ) Ms

6.3 Wet Volumetric Stack Gas Flow Rate, Actual Conditions, cubic feet 

per minute

( )( ) ⎟

⎠

⎞ ⎜

⎝

⎛ = min

sec60 AVQ ssa
Page 5 

6.4 Dry Volumetric Stack Gas Flow Rate, Corrected to Standard Conditions, 

cubic feet per hour

Qs = V( )s ( ) As

3600 sec

hr

⎛

⎝ ⎞ ⎠ ( ) Mfd

Ps

Ts

⎛

⎝ ⎞ ⎠ 

Tstd

Pstd

⎛

⎝ ⎞ ⎠ 

7. ISOKINETICS DETERMINATION

7.1 Raw Isokinetic Variation, Percent

Raw %I = 

( ) Ts°R ( ) K4 ( ) Vlc +

Vm

Tm°R

⎛ 

⎝ ⎞ ⎠ 

⎛ 

⎝ 

⎞ 

⎠ Pbar +

ΔH

13.6

⎛ 

⎝ ⎞ ⎠ 

⎛ 

⎝ 

⎞ 

⎠ 

( ) 60 ( ) Vs ( ) Ps ( ) θ ( ) An

⎛

⎝ 

⎜ 

⎜ ⎜ 

⎞ 

⎠ 

⎟ 

⎟ 100

K4 = 0.002676

7.2 Isokinetic Variation, Percent

%I = ( ) Ts°R ( ) Vm(std) (Pstd)

( ) 60 ( ) Vs ( ) Ps ( )θ ( ) An ( ) Mfd ( ) Tstd

⎛

⎝ 

⎜ ⎞ 

⎠ 

⎟ 100

7.3 Determining K-Factor

K = ( ) 846.72 Dn

4

( )( ) ΔH@ Cp

2

( ) Mfd

2

( ) (Md)(Tm°R)(Ps)

( ) Ms ( ) Ts°R ( ) Pm

⎛

⎝ 

⎜ ⎞

⎠

⎟ 

7.4 Determining DH

ΔH =[ ] K ΔP

8. POLLUTANT DETERMINATIONS 

8.1 Concentration of Pollutant, Grains per Dry Standard Meter

Csd = 

Mn

Vmstd

⎛ 

⎝ ⎞ ⎠ 

g

1,000,000 μg

⎛

⎝ 

⎜ ⎞ 

⎠ 

15.432 grains

g

⎛

⎝ 

⎜ ⎞ 

⎠ 
Page 6 

8.2 Concentration of Pollutant, Milligrams per Dry Standard Cubic Meter

⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

μ

⎟

⎠

⎞ ⎜

⎝

⎛

3

3

mstd

n

sd

m

ft 5.315

g 1,000

g

V

M = C 3

8.3 Emission Rate for Pollutant, Grains per Dry Standard Cubic Foot —> 

Pounds per Hour

Mp = C( ) sd ( ) Qs

lb

7000 gr

⎛

⎝ 

⎜ ⎞ 

⎠ 

8.4 Emission Rate for Pollutant, Pounds per Hour—> Pounds per Million BTU

( ) ⎟

⎠

⎞ ⎜

⎝

⎛

− ⎟

⎟

⎠

⎞ ⎜

⎜

⎝

⎛ = %9.20 2

9.20

Q O

F

s

M M p

pBtu

8.5 Emission Rate of Pollutant based on Production Rate, Pounds per Hour—> 

Pounds per Ton

Mpro = Mp

P

⎛

⎝ ⎞⎠

8.6 Emission Rate of Pollutant, Actual Flowrate, Parts per Million ->

Pounds per Hour

Mp = 

Mn

1,000,000

⎛

⎝ 

⎞ 

⎠ ( ) Qa

m3

35.315 dscf

⎛

⎝ 

⎜ ⎞ 

⎠ 

mole

0.02404 m3

⎛ 

⎝ ⎞ ⎠ 

Ps

Ts°R

⎛ 

⎝ ⎞ ⎠ 

Tstd

Pstd

⎛ 

⎝ ⎞ ⎠ 

MW g

mole

⎛ 

⎝ ⎞ ⎠ 

lb

453.6 g

⎛

⎝ 

⎜ ⎞

⎠

8.7 Emission Rate of Pollutant, Standard Flowrate, Parts per Million ->

Pounds per Hour

Mp = 

Mn

1,000,000

⎛

⎝ 

⎞ 

⎠ ( ) Qs

m3

35.315 dscf

⎛

⎝ 

⎜ ⎞ 

⎠ 

mole

0.02404 m3

⎛ 

⎝ ⎞ ⎠ 

MW g

mole

⎛ 

⎝ ⎞ ⎠ 

lb

453.6 g

⎛

⎝ 

⎜ ⎞

⎠
Page 7 

9. POLLUTANT CORRECTIONS 

9.1 Concentration Correction to 12% Carbon Dioxide

Cs12 = C( )s

12

%CO2dry

⎛

⎝ 

⎞

⎠

9.2 Concentration Correction to 50% Excess Air Concentration

Cs50 = C( )s

100 +%EA

150

⎛

⎝ ⎞ ⎠ 

9.3 Concentration Correction to 50% Excess Air Concentration using 

Raw ORSAT Data

Cs50 = Cs

1- ( ) 1.5 ( ) %O2dry − ( ) 0.133 ( ) %N2dry − ( ) 0.75 ( ) %COdry

21

⎛ 

⎝ 

⎜ ⎞ 

⎠ 

9,4 Leak Rate Adjustment

Vm = [ ] Vm − ( ) L1 − La θ − ( ) L1 − La

i = 2

N

∑ θi − (Lp − La)θp

9.5 Concentration of Pollutant, Corrected for Moisture, ppm

Mn = 

Mn

Mfd

⎛

⎝ ⎞

⎠

9.6 Concentration of Volatile Organic Compounds, Corrected to

Standard Conditions, ppm as Carbon

Mn VOC [ ] = 

( ) Mnp

3 Carbon

Propane

⎛ 

⎝ 

⎜ ⎞ 

⎠ 

Mfd

⎛

⎝ 

⎜ 

⎜ ⎜ 

⎞ 

⎠ 

⎟ 

⎟ ⎟ 

9.7 Concentration of Pollutant, Corrected for Oxygen, ppm

Mn = M( )n

20.9 - %O2Corr

20.9 - %O2dry

⎛

⎝ 

⎞ 

⎠ 
Page 8 

9.8 Concentration of Pollutant (CO, NOx), Corrected for Carbon Dioxide, ppm

Mn = M( )n 1 - %CO2dry

100

⎛

⎝ ⎞ ⎠ 

10. EFFICIENCY EQUATIONS 

10.1 Capture Efficiency, percent

%C = Mp(outlet )

Mp(inlet)

⎛

⎝ 

⎞ 

⎠ 100

10.2 Destruction Reduction Efficiency, percent

%DRE = Mp(inlet) - Mp(outlet )

Mp(inlet )

⎛

⎝ 

⎞ 

⎠ 100

11. METHOD 8 EQUATIONS 

11.1 Emission Rate of Pollutant (SO2), pounds/cubic foot

CSO 2 = ( ) K3

N V( ) t − Vtb

Vsolution

Valiquot

⎛ 

⎝ 

⎞ 

⎠ 

Vmstd

⎛

⎝ 

⎜ 

⎜ ⎜ 

⎞ 

⎠ 

⎟ 

⎟ 

K3 = 7.061 ×10-5 lb / meq

11.2 Emission Rate of Pollutant (H2SO4), pounds/cubic foot

CH 2SO 4 = ( ) K2

N V( ) t − Vtb

Vsolution

Valiquot

⎛ 

⎝ 

⎞ 

⎠ 

Vmstd

⎛

⎝ 

⎜ 

⎜ ⎜ 

⎞

⎠

⎟ 

⎟ 

K2 =1.081× 10-4 lb / meq
Page 9 

12. NOMINAL NOZZLE SIZE 

12.1 Nozzle Determination, inches

Dn = ( ) 0.0358 ( ) Qm ( ) Pm

( ) Tm°R ( ) Cp ( ) Mfd

( ) Ts°R ( ) Ms

( ) Ps Δ P ⎛ 

⎝ ⎜ ⎜ 

⎞ 

⎠ ⎟ ⎟ 

12.2 PM10 Nozzle Determination, inches

 

Dn = Qa

Cp DP ( ) 85.49 * 3.1416 *60

576

⎛ 

⎝ ⎜ ⎞ ⎠ ⎟ Ts°R

( ) Ps ( ) Ms

⎛ 

⎝ 

⎜ ⎜ 

⎞ 

⎠ 

⎟ ⎟ 

Qa is obtained from PM10 manual (acfm) 

13. F-FACTOR EQUATIONS 

Note: All Cs values must be in pounds per standard cubic foot (lbs/scf) 

 See EPA 40 CFR 60, App. A, Method 9, Sec. 2.0.

Conversion Factors for Concentration 

From To Multiply by

g/scm ng/scm 1.00E+09 

mg/scm ng/scm 1.00E+06 

lb/scf ng/scm 1.60E+13 

ppm SO2 ng/scm 2.66E+06 

ppm NOx ng/scm 1.91E+06 

ppm SO2 lb/scf 1.66E-07 

ppm NOx lb/scf 1.19E-07 

13.1 Oxygen-Based F Factor, Dry Basis

E = ( ) Cd ( ) Fd

20.9

20.9 − %O2dry

⎛

⎝ 

⎞ 

⎠ 

13.1a Oxygen-Based F Factor, Dry Basis, correcting to 7% Oxygen

E = ( ) Cd ( ) Fd

20.9 − 7.0

20.9 − %O2dry

⎛

⎝ 

⎞ 

⎠ 
Page 10 

13.2 Oxygen-Based F Factor, Wet Basis

E = ( ) Cw ( ) Fd

20.9

20.9 −%O2dry

⎛

⎝ 

⎞

⎠

13.3 Oxygen-Based F Factor, Dry/Wet Basis

E = ( ) Cw ( ) Fw

( ) Mfd

20.9 − %O2dry

20.9

⎛

⎝ ⎞ ⎠ 

Note: When pollutant is measured on wet basis and %O2 is measured on a dry basis.

13.4 Oxygen-Based F Factor, Dry/Wet Basis

E = ( ) Cw ( ) Fd ( ) 20.9 ( ) Mfd

20.9 − %O2wet

⎛

⎝ 

⎞

⎠

Note: When pollutant is measured on dry basis and %O2 is measured on a wet basis.

E = ( ) Cdry ( ) Fc

100

%CO2dry

⎛

⎝ 

⎞

⎠

13.5 Carbon Dioxide-Based Factor, Wet Basis

E = ( ) Fc ( ) Cwet

100

%CO2wet

⎛

⎝ ⎞ ⎠ 

13.6 Carbon Dioxide-Based Factor, Dry/Wet Basis

E = ( ) Cw ( ) Fc

Mfd

⎡ 

⎣ ⎢ ⎤ 

⎦ ⎥ 

100

%CO2dry

⎛

⎝ 

⎞ 

⎠ 

Note: When pollutant is measured on wet basis and %O2 is measured on a dry basis.

13.7 Carbon Dioxide-Based Factor, Dry/Wet Basis

E = ( ) Cdry ( ) Mfd ( ) Fc 100

%CO2 wet

⎛

⎝ 

⎞ 

⎠ 

Note: When pollutant is measured on dry basis and %O2 is measured on a wet basis.
Page 11 

14. CYCLONIC FLOW 

14.1 Average Stack Gas Velocity, feet per second (Cyclonic), used for 

Isokinetic Determination Only

Vs[cyc] = K( )p ( ) Cp ( ) ΔP

Ts

( ) Ps ( ) Ms

14.2 Average Stack Gas Velocity, feet per second (Laminar)

Vs[lam] = K( )p ( ) Cp ( ) cosφ Δ( ) P

Ts

( ) Ps ( ) Ms

Note: When using Microsoft Excel, the Cosine function is in Radians. To convert Degrees to Radians multiply 

by π/180 (where π=3.1416). 

14.3 Determination of Sampling Time

Minutes / Point = cosφ( ) Base Time

14.4 Average Differential Pressure

ΔPvavg =

∑cosφ ΔP

n

⎡ 

⎣ ⎢ 

⎤ 

⎦ ⎥ 

2

14.5 Axial Volumetric Flow Rate

Qs = KpCpAs

Ts

PsMs

( ) ΔPi cos φi

i

n

∑

n

15. METHOD 5 POST TEST CALIBRATION 

15.1 Alternative Method 5 Post-Test Calibration

Yqa = θ

Vm

⎛ 

⎝ ⎞ ⎠ ( ) ΔHavg

Pstd

Tstd

⎛ 

⎝ ⎞ ⎠ ( ) Qm 2

( ) Tm°R ( ) Md(AMB)

( ) ΔH @ Pbar +

ΔHavg

13.6

⎛ 

⎝ ⎞ ⎠ ( ) Md
Page 12 

15.2 CRITICAL ORIFICE

Vmstd = K1 ( )( ) Vm

Pbar +

ΔH

13.6

Tm°R

⎛

⎝ 

⎜ 

⎜ 

⎞

⎠

⎟ ⎟ Vcr(std) = K( ) co ( )θ Pbar

Tamb

⎛

⎝ 

⎞

⎠ Y = Vcr(std)

Vm(std)

⎛

⎝ 

⎞

⎠

16. WET BULB/DRY BULB 

16.1 %Moisture at Saturation As a Function of Temperature

W2 = 10

6.6911− 3144

TW +390.86

⎛

⎝ 

⎜ ⎜ 

⎞

⎠ 

⎟ ⎟ 

⎛

⎝ 

⎜ ⎜ 

⎞

⎠ 

⎟ ⎟ 

Pb +

Ps

13.6

⎛ 

⎝ ⎞ ⎠ 

W2=Value in %Moisture at Saturation As a Function of Temperature Table 

* Note: Use Equation when Stack Temperature is greater than 211°F or less than 50°F. 

Also use Equation if the absolute value of the Static Stack Pressure is greater than 1.

16.2 Percent Moisture in Stack Gas

%H2O = W2 − ( ) 0.000367 Td − Tw ( ) 1+

Tw − 32

1571

⎛ 

⎝ ⎞ ⎠ 

⎡ 

⎣ ⎢ ⎤ 

⎦ ⎥ ( ) 100

16.3 Water Vapor in the Stack Gas, Proportion by Volume

Bws = %H2O

100

17. VOLUME PER POINT (ISOKINETIC TESTING) 

17.1 Volume per Point

Vm

Point = 60 V( )s ( ) Ps ( ) θ ( ) An (Mfd )(Tm°R)

( ) Υ Pbar + ΔH

13.6

⎛ 

⎝ ⎞ ⎠ ( ) Ts°R
Page 13 

18. INSTRUMENT TESTING 

18.1 EFFLUENT GAS CONCENTRATION

Cgas = ( ) Cavg − Co

Cma

Cm − Co

⎛

⎝ ⎞ ⎠ 

[EPA 40 CFR 60, App. A, Method 6C, 8.0; Method 7E, 8.0]

18.2 Concentration of Carbon Monoxide, Corrected for Carbon Dioxide, ppm

Mn CO [ ] = M( ) n CO [ ] 1 - %CO2

100

⎛

⎝ ⎞

⎠

[EPA 40 CFR 60, App. A, Method 10, 9.0]

18.3 SYSTEM CALIBRATION BIAS

System Calibration Bias = System Cal. Response - Analyzer Cal. Response

Span

⎛

⎝ 

⎜ ⎞ 

⎠ 100

18.4 DRIFT CHECK

%Drift = Final System Cal. Response - Initial System Cal. Response

Span

⎛

⎝ 

⎜ ⎞ 

⎠ 100

19. HEAT INPUT 

19.1 Heat Input Rate

HI = Qs

F

⎛

⎝ ⎞ ⎠ 

20.9 −%O2

20.9

⎛

⎝ ⎞

⎠
Page 14 

20. CONVERSION FACTORS 

Conversion Factors for Concentration 

From To Multiply By Reference 

g/scm ng/scm 1.00E+09 EPA 40 CFR 60, App. A, 

Method 19 

mg/scm ng/scm 1.00E+06 EPA 40 CFR 60, App. A, 

Method 19 

lb/scf ng/scm 1.60E+13 EPA 40 CFR 60, App. A, 

Method 19 

ppm SO2 ng/scm 2.66E+06 EPA 40 CFR 60, App. A, 

Method 19 

ppm NOx ng/scm 1.91E+06 EPA 40 CFR 60, App. A, 

Method 19 

ppm SO2 lb/scf 1.66E-07 EPA 40 CFR 60, App. A, 

Method 19 

ppm NOx lb/scf 1.19E-07 EPA 40 CFR 60, App. A, 

Method 19 

scf m3 0.02832 EPA 40 CFR 60, App. A, 

Method 5 

g/ft3 gr/ft3 15.43 EPA 40 CFR 60, App. A, 

Method 5 

g/ft3 lb/ft3 2.205 X 10-3 EPA 40 CFR 60, App. A, 

Method 5 

g mg 0.001 EPA 40 CFR 60, App. A, 

Method 5 
Page 15 

21. CONSTANTS

Constants 

Abbreviation Name Value Units Reference 

Kp Pitot Constant 85.49 EPA 40 CFR 

60, App. A, 

Method 2 

Mw Molecular 

Weight of 

Water 

18.0 lb/lb-mole EPA 40 CFR 

60, App. A, 

Method 5 

P(std) Standard 

Pressure 

29.92 In. Mercury EPA 40 CFR 

60, App. A, 

Method 2 

T(std) Standard 

Temperature 

528 degrees Rankin EPA 40 CFR 

60, App. A, 

Method 2 

R Ideal gas 

constant 

21.85 ft3/lb-mole EPA 40 CFR 

60, App. A, 

Method 5 

%O2(amb) Ambient 

Percent Oxygen

20.9 %O2 by volume EPA 40 CFR 

60, App. A, 

Method 3B 

%CO2(amb) Ambient 

Percent Carbon 

Dioxide 

0.03 %O2 by volume EPA 40 CFR 

60, App. A, 

Method 3B 

ρω Density of 

Water 

0.002201 lb/ml EPA 40 CFR 

60, App. A, 

Method 5 

π PI 3.1416 
22. NOMENCLATURE 

 Symbol Description Unit 

 An Area of the Nozzle Square feet (ft2) 

 As Area of the Stack Square feet (ft2) 

 Bws Water vapor in the stack gas Proportion by volume 

 Bwa Moisture content of ambient air Proportion by volume 

 Cdry Particulate concentration, dry basis Mass/Volume 

 CH2SO4 Emission Rate of Hydrogen Sulfide Milligrams per cubic foot 

 Cp Pitot Coefficient Dimensionless 

 Cs Particulate concentration Mass/Volume 

 Cs12 Concentration correction to 12% Mass/Volume 

 Carbon Dioxide 

 Cs50 Concentration correction to 50% Mass/Volume 

 Excess Air 

 Csd Particulate concentration Grains per dry standard 

 cubic feet (gr/dscf) 

 Cwet Particulate concentration Mass/Volume, wet basis 

 Dn Diameter of the Nozzle Inches (in.) 

 dscf Unit of Flow measurement Dry standard cubic feet 

 Ds(depth) Depth of the stack Inches (in.) 

 Ds(width) Width of the stack Inches (in.) 

 E Emission rate Mass per heat BTU input 

 

Page 16 
 Symbol Description Unit 

 

 F F-Factor Using Fc or Fd

 Fc F-Factor, wet basis Using Cs and %CO2 on 

 a wet or dry basis

 Fd F-Factor, dry basis Using Cs and %O2 on 

 a dry basis 

 Fw F-Factor Using Cws and %O2 on 

 a wet basis 

 ft Unit of measurement Feet 

 g Unit of measurement Grams 

 gr Unit of measurement Grains 

 HI Heat Input mmBTU/hr 

 hr Unit of time measurement Hour 

 in Unit of measurement Inch 

 K Constant Constant used for DGM 

 K2 Constant used for H2SO4 titrations 7.061 X 10-5 lb/meq 

 K3 Constant used for SO2 titrations 7.061 X 10-5 lb/meq 

 K4 Constant used for Raw Isokinetics 2.676 X 10-3 lb/meq 

 Kcf Constant Correction Factor Constant 

 Kco Constant for Critical Orifice Constant 

 Kp Unit Conversion Constant for Velocity 85.49 

 La Average Leakrate Cubic feet 

 lbs Unit of Weight measurement Pounds 

 Li Initial Leakrate Cubic feet 

 

Page 17 
 Symbol Description Unit 

 

 Lp Post Leakrate Cubic feet 

 Md Molecular weight of stack gas, dry basis Pound per pound-mole 

 (lb/lb-mole) 

 Mfd Mole fraction dry basis of stack gas Percent 

 min Unit of time measurement Minutes 

 mg Unit of weight measurement Milligrams

 Mn Mass pollutant found in sampling train Micrograms (μg) 

 MnVOC Mass pollutant (VOC) determined with parts per million (ppm) 

 FID (as carbon) 

 MnP Mass pollutant (VOC) determined with parts per million (ppm) 

 FID (as propane) 

 Mp Total pollutant mass emissions rate Pounds per hour (lb/hr) 

 Mpro Total pollutant mass emissions rate Pounds per ton (lb/ton) 

 based on production rate 

 Mp(Off) Total pollutant mass emissions rate, Pounds per hour (lb/hr) 

 while the scrubber is Off 

 Mp(On) Total pollutant mass emissions rate Pounds per hour (lb/hr) 

 while the scrubber is On 

 Mp(inlet) Total pollutant mass Pounds per hour (lb/hr) 

 emissions rate, inlet 

 Mp(outlet) Total pollutant mass Pounds per hour (lb/hr) 

 emissions rate, outlet 

 Ms Molecular weight of stack gas, Pound per pound-mole 

 wet basis (lb/lb- mole) 

 MW Molecular weight of pollutant Grams per mole (g/mole) 

 n Number of sampling points Number 

 

Page 18 
 Symbol Description Unit 

 

 Pbar Barometric pressure Inches of mercury (in. of Hg) 

 Pg Pressure of stack gas Inches of water (in. of H2O) 

 (static pressure) 

 PMR Pollutant Mass Rate Mass per volume 

 ppm Unit of Measurement Parts per Million 

 Ps Absolute stack gas pressure Inches of mercury (in. of Hg) 

 Ps(sgd) Sample Gas Density Pounds per cubic foot 

 Ps(std) Absolute stack gas pressure, Inches of mercury (in. of Hg) 

 Pstd Standard pressure, 29.92 in. Hg Inches of mercury 

 (in. of Hg) 

 Qa Wet volumetric stack gas Actual cubic feet/hour 

 flow rate at actual conditions (acf/hr) 

 Qm Orifice Meter Calibration Dry standard cubic feet 

 per minute (dscf/min) 

 (Qm=0.75 cfm) 

 [at standard conditions] 

 Qs Dry Volumetric Stack Gas Flow Rate Dry standard cubic feet 

 corrected to Standard Conditions per hour (dscf/hr) 

 Qs(avg) Dry Volumetric Stack Gas Flow Rate Dry standard cubic feet 

 corrected to Standard Conditions per hour (dscf/hr) 

 Average flow before and after flow 

 measurement 

 Td Absolute dry gas stack temperature Degrees Rankin (°R) 

 Dry Bulb Temperature 

 Tm°R Absolute dry gas meter temperature Degrees Rankin (°R) 

 Ts°R Absolute stack temperature Degrees Rankin (°R) 

 Tstd Standard temperature (528°R) Degrees Rankin (°R) 

 

Page 19 
 Symbol Description Unit 

 

 Tw Absolute wet gas stack temperature Degrees Rankin (°R) 

 Wet Bulb Temperature 

 T°C Temperature in Celsius Degrees Celsius (°C) 

 T°F Temperature in Fahrenheit Degrees Fahrenheit (°F) 

 T°R Temperature in Rankin Degrees Rankin (°R) 

 sec Unit of time measurement Seconds 

 Valiquot Volume of Aliquot Milliliter (ml) 

 Vcr(std) Volume of gas passed through the critical Dry standard cubic feet (dcf) 

 orifice, correct to standard conditions. 

 Vlc Volume of water vapor condensed in Milliliter (ml) 

 the impingers 

 Vm Volume of gas sample as measured by the Dry cubic feet (dcf) 

 dry gas meter 

 Vm(std) Volume of gas sample as measured by the Dry standard cubic feet 

 dry gas meter, corrected to standard (dscf) 

 conditions 

 Vm(std)(Total) Volume of gas sample as measured by the Dry standard cubic feet 

 dry gas meter, corrected to standard (dscf) 

 conditions 

 Vs Average stack gas velocity Feet per second (ft/sec) 

 Vsolution Volume of Solution (Sample) Milliliter (ml) 

 Vwsg Weight of water vapor condensed in Grams (g) 

 silica gel 

 Vw(std) Volume of water vapor in the gas sample, Standard cubic feet (scf) 

 corrected to standard conditions 

 Vwc(std) Volume of water vapor condensed in Standard cubic feet (scf) 

 impingers, corrected to standard conditions 

 

Page 20 
 Symbol Description Unit 

 Vt Volume of Titrant used Milliliters (ml) 

 Vtb Volume of Titrant used on Blank Milliliters (ml) 

 Vwsg(std) Volume of water vapor condensed in Standard cubic feet (scf) 

 silica gel, corrected to standard 

 conditions 

 Wsg Total weight of Gas sampled Pounds 

 W2 Calculated constant, saturation %H2O Pounds 

 at Tw 

 Y Dry gas meter calibration factor Dimensionless 

 Yaq Dry gas meter calibration check value Dimensionless 

ΔH@ Pressure drop across orifice meter of Inches of water (in. of H2O) 

 dry gas meter 

ΔH Average pressure differential across Inches of water (in. of H2O) 

 the orifice 

ΔP Average velocity head of stack gas Inches of water (in. of H2O) 

∆P Average squareroot velocity head of Inches of water (in. of H2O) 

 stack gas 

 %C Percent Capture Efficiency Percent (%) 

 %COdry Percent carbon monoxide by volume, Percent (%) 

 dry basis 

 %CO2dry Percent carbon dioxide by volume, dry Percent (%) 

 basis 

 %CO2wet Percent carbon dioxide by volume, wet Percent (%) 

 basis 

 %DRE Percent Destruction Reduction Efficiency Percent (%) 

 %EA Percent Excess Air Percent (%) 

Page 21 
Page 22 

 Symbol Description Unit 

 %I Isokinetic Variation Percent (%) 

 Raw %I Raw Isokinetic Variation Percent (%) 

 %N2 Percent nitrogen by volume, dry basis Percent (%) 

 %O2dry Percent oxygen by volume, dry basis Percent (%) 

 %O2wet Percent oxygen by volume, wet basis Percent (%) 

 %O2Corr Percent oxygen Correction Factor Percent (%) 

 %Scrubber Percent Scrubber Efficiency Percent (%) 

θ Total sampling time Minutes (min) 

θi Initial sampling time Minutes (min) 

θp Final sampling time Minutes (min) 

π pi, π = 3.1416 Constant 

 ø Angle between velocity vector and Degrees 

 stack axis