## Date: November 6 , 2014

To: Jeff Telander, EPA/OAQPS/SPPD

From: Thomas Holloway

Sub ject: Monitoring and Testing Requirements and Costs for the Clay Ceramic s NESHAP

I. Introduction

In accordance with section 112 of the Clean Air Act (CAA), the U.S. Environmental

Protection Agency (EPA) established national emission standards for hazardous air pollutants

(NESHAP) on May 16, 2003 for the clay ceramics manufacturing industr y , specifically the

sanitaryware and ceramic tile industry sectors. Sanitaryware includes plumbing and bathroom

fixtures such as toilets and sinks. Ceramic tile is used to cover floors and walls . The NESHAP

regulated emissions of hydrogen fluoride (HF)

, hy drogen chloride (HCl), and particulate matter

(PM)

— a surrogate for hazardous air pollutant (HAP) metals

— from new and reconstructed kilns

located at clay ceramics facilities

. On March 13, 2007, the D.C. Circuit Court vacated the

emission standards for clay ceramics manufacturing due to issues associated with the

methodology used to determine the minimum regulatory “floors” for new and existing units

. 1



## Therefore

, the EPA is propo sing new standards for clay ceramics manufacturing

, includ ing limits

for HF, HCl, mercury (Hg), non

- Hg HAP metals (specifically, the PM surrogate) , and

dioxins/furans (D/F)

.

The list of affected sources to be regulated ha s been expanded to include new and

existing kilns, spray dryers (ceramic tile only), press dryers (floor tile only), and spray glaze

operations (sanitaryware and floor tile only)

. The facilities that would be subject to the proposed

NESHAP based on current operations include three sanitaryware facilities. The other clay

ceramic s facilities ( w all and floor tile facilities) have taken the necessary steps to become

synthetic area sources ( i.e. , have obtained a federally enforceable limit reducing emissions below

major source thresholds), and would not be subject to the major source clay ceramics NESHAP.

Th e purpose of th is memorandum is to present the monitoring and testing requirements for the

proposed clay ceramics NESHAP and the estimated costs for each requirement.

1 

### Sierra Club v. EPA , 479 F.3d 875 (D.C. Cir. 2007).

## 2 II. Monitoring Requirements and Costs

Monitoring requirements are presented in this mem orandum for each emission control

scenario for the clay ceramics industry. T hese requirements were selected based upon a

determination of the information necessary to ensure that the emission standards are being

followed and that emission control devices a nd equipment are maintained and operated properly.

These requirements are intended to ensure compliance with the clay ceramics standards without

imposing a significant additional burden for the facilities that must implement them. Table 1

summarizes the cl ay ceramics monitoring requirements and costs.

For a ffected sources not equipped with act ivated carbon injection systems

, compliance

with the D/F emission limit would be demonstrated by monitoring source operating temperature

. T h e specifics of th is monitoring requirement vary depending on the type of affected source.

Dioxin/furan compounds are typically formed at temperatures between 200 and 450 degrees

Celsius ( °C ) (392 and 842 degrees Fahrenheit [ °F ] ) and typically destroyed at temperatures

ranging from 977°C (1,791°F)

, at a retention time of 1 second (sec)

, to 1,000°C (1,832°F), at a

retention time of 0.5 sec (EPA, 2006)

. To minimize the formation of D/F , clay ceramics facilities

would need to limit the operation of their affected sources in the temperature range where D/F

compounds are formed. However, some affected sources (kilns and spray dryers) typically have

operating temperatures above this range, and some (press dryers) typically have operating

temperatures b elow this range ; in addition, kilns typically have operating temperatures in the

range where D/F destruction occurs

. (Abraczinskas and Marinshaw, 1999) Consequently

, the

temperature monitoring requirement for kilns and spray dryers is recommended to be a m inimum

temperature limit to operate at or above ; for press dryers, it is recommended to be a maximum

temperature limit to operate at or below. The operating limits would be established during the

D/F performance tests for the affected sources. Table 2 comp ares the operating temperatures for

kilns, spray dryers, and press dryers to the D/F formation and destruction temperatures

.

T he costs to monitor kiln process rate and source operating temperature are expected to

be included in the cost of normal source op eration. T he control device monitoring costs are, in

most cases, expected to be included in the cost of the control device. Exceptions include the cost

to install and operate a bag leak detector (BLD) and the cost to conduct daily visible emissions

(VE) mo nitoring using EPA Method 22, “Visual Determination of Fugitive Emissions from

Material Sources and Smoke Emissions from Flares,” 40 CFR part 60, appendix A

- 7.

The BLD costs were determined using an EPA cost model (EPA, 2007) , with capital

related costs updated to 2011 dollars using the Chemical Engineering Plant Cost Index (CEPCI)

(CE

, 2012 ) . Table 3 documents the cost elements included in the BLD costs.

The VE monitoring costs were calculated based on the labor requirements associated with

conducting a daily 15

- minute VE check, preparing for and documenting the results of the VE

checks, and having two people attend a VE training course every 5 years (Shrager

, 2003)

. The

VE monitoring costs are also in 2011 dollars. Table 4 documents the calculation of th e VE

monitoring costs. A summary of the monitoring costs for each affected facility is presented in

Table 5

.

## 3 III. Testing Requirements and Costs

Testing requirements are presented in this memorandum for each pollutant (or set of

pollutants) and affected s ource type for which there is an emission limit in the proposed clay

ceramics NESHAP. Each facility subject to the proposed clay ceramics NESHAP would conduct

an initial performance test at the stack of each affected source using specified EPA test methods

to demonstrate initial compliance with all applicable emission limits. These facilities would

conduct a performance test for each affected source before renewing their title V operating

permit or at least every 5 years following the initial performance te st, as well as when an

operating limit parameter value is being revised. During these performance tests, e ach

sanitaryware facility subject to the proposed clay ceramics NESHAP would measure emissions

of HF, HCl, Hg, PM, and D/F from the affected kiln stac ks and emissions of PM from the

affected glaze spray booth stacks.

The performance test costs were estimated assuming that the sanitaryware facilities

would measure emissions from their affected kiln stacks using the following methods:

• HF, HCl : EPA Method 26A, “Determination of Hydrogen Halide and Halogen Emissions

from Stationary Sources

- Isokinetic Method,” 40 CFR part 60, appendix A

- 8

• Hg : EPA Method 29, “Determination of Metals Emissions from Stationary Sources,” 40

CFR part 60, appendix A

- 8

• D/F : EPA Method 23, “Determination of Polychlorinated Dibenzo

- p

- Dioxins and

Polychlorinated Dibenzofurans From Stationary Sources,” 40 CFR part 60, appendix A

- 7

The sanitaryware facilities were assumed to measure PM emissions from their glaze

spray booth stac ks using EPA Method 5, “Determination of Particulate Emissions from

Stationary Sources,” 40 CFR part 60, appendix A

- 3 . The Method 26A, Method 29, and Method 5

tests would consist of three runs, at 1 hour each. The Method 23 test would consist of three runs

, at 2 hours each.

Because the numbers and types of affected sources differ for each sanitaryware facility

subject to the clay ceramics NESHAP, a separate set of test costs was developed for each facility.

The test costs for each facility are detailed in A ttachment A of this memorandum. The labor and

equipment rental rates and analytical laboratory costs are detailed in Attachment B. A summary

of the test costs for each facility is presented in Table 5

.

IV. References

Abraczinskas, M. and Marinshaw, R. 1999

. Characterization of the Ceramic Manufacturing

Industry. Memorandum from Mike Abraczinskas and Rick Marinshaw, MRI, to Susan

Zapata, EPA. December 3, 1999.

BLS ( U.S. Department of Labor, Bureau of Labor Statistics ). 201 2

. May 2011 National

Industry

- Specif ic Occupational Employment and Wage Estimates, NAICS 327100

- Clay

Product and Refractory Manufacturing. Occupational Employment Statistics

. March 27,

2012. Available at: http://www.bls.gov/oes/2011/may/naics4_327100.htm

.

## 4 CE ( Chemical Engineering). 201 2

. Chemical Engineering Plant Cost Index.

EPA ( U.S. Environmental Protection Agency). 1997. Fabric Filter Bag Leak Detection

Guidance. Publication No. EPA

- 454/R

- 98

- 015. Septem ber 1997. Available at :

http://www.epa.gov/ttnemc01/cem/tribo.pdf

.

EPA ( U.S. Environmental Protection Agency ) . 2006. An Inventory of Sources and

Environmental Releases of Dioxin

- Like Compounds in th e United States for the Years 1987,

1995, and 2000. Publication No. EPA/600/P

- 03/002F. November 2006. Available at:

http://www.epa.gov/ncea/pdfs/dioxin/2006/dioxin.pdf

.

EPA ( U.S. Environmental Protection Agency )

. 2007. CEMS Cost Model. Technology Transfer

Network, Emission Measurement Center, Continuous Emission Monitoring

– Information,

Guidance, etc. March 7, 2007. Available at : http://www.epa.gov/ttn/emc/cem/cems.xls

.

Shrager, B. 2003. Final Rule: Monitoring and Monitoring Costs. Memorandum from Brian

Shrager, RTI International, to Mary Johnson, EPA/ESD/CG. February 26, 2003.

## 5 Table 1. Summary of Monitoring Requirements and Costs 1



### Emission

control Monitor t ype/

operation/p rocess Monitoring requirements Emission limits

for which

compliance is

demonstrated Monitoring c osts

, 2011$

Capital

($) Annual

($/yr)

Dry injection

fabric filter

(DIFF) or dry

lime scrubber/

fabric filter

(DLS) Bag leak detector

or Install and operate a bag leak detector in accordance with Fabric

Filter Bag Leak Detection Guidance

. (EPA, 1997) PM $37,888 $12,345

Daily VE check Perform daily 15

- minute Method 22 VE check. Can reduce

frequency to weekly after 30 days with no VE. PM

-- 2 $2,984

Lime injection rate Verify that lime is free

- flowing via pressure (flow sensors); weight

(load cells); or other system. Record all results. Record feeder

setting once each shift, on a per ton of fired product basis. HF, HCl

-- 3

Fabric filter Bag leak detector

or Install and operate a bag leak detector in accordance with Fabric

Filter Bag Leak Detection Guidance

. (EPA, 1997) PM $37,888 $12,345

Daily VE check Perform daily 15

- minute Method 22 VE check. Can reduce

frequency to weekly after 30 days with no VE. PM

-- 2 $2,984

Wet scrubber Pressure drop Continuously monitor the pressure drop across the scrubber.

Determine and record 3

- hour block averages. PM

-- 3

pH Continuously monitor the scrubber liquid pH. Determine and

record 3

- hour block averages. HF, HCl

Liquid flow rate Continuously monitor the scrubber liquid flow rate. Determine and

record 3

- hour block averages. All pollutants

Chemical addition

rate Continuously monitor the scrubber chemical feed rate (if

applicable). Determine and record 3

- hour bloc k averages. HF, HCl

Activated

carbon injection

system Activated carbon

flow rate Monitor carbon flow rate once per shift. Record carbon flow rate for

15 minutes each shift. Hg, D/F

-- 3

Water curtain Periodic inspection Conduct a daily inspection to verify the presence of water flow to

the wet control system, conduct weekly visual inspections of the

system ductwork and control equipment for leaks, and conduct

annual inspections of the interior of the control equipment (if

applicable) to determine the structural integrity and condition of the

control equipment. PM

-- 3

Baffles Annual inspection Conduct an annual visual inspection of the baffles to confirm the

baffles are in place. PM

-- 3

## 6 Emission

control Monitor t ype/

operation/p rocess Monitoring requirements Emission limits

for which

compliance is

demonstrated Monitoring c osts

, 2011$

Capital

($) Annual

($/yr)

No control Daily VE check Perform daily 15

- minute Method 22 VE check; can reduce

frequency to weekly after 30 days with no VE. PM

-- 2 $2,984

Kiln process rate If last calculated total facility maximum potential HCl

- equivalent

not ≤ limit, collect and record kiln process rate data and reduce

data to 3

- hour averages. HF, HCl

-- 4

Temperature 5 Continuously monitor the operating temperature . Determine and

record 3

- hour block averages. D/F

-- 4

1 Reference: Shrager, 2003.

2 No capital cost

3 No cost; included in control device costs

4 No cost; included in source operation costs

5 To be monitored by kilns with no activated carbon injection control.

## 7 Table 2. Comparison of Clay Ceramic Affected Source Operating Temperatures to Dioxin/Furan Formation/Destruction

Temperatures

Parameter Temp

. , °C Temp

., °F

Notes Refere nce Min

. Max

. Min

. Max

.

D/F formation 200 450 392 842 Maximum formation at 350°C (662°F) EPA, 2006 ( section 2 )

D/F destruction 977 1

, 000 1

, 791 1

, 832 Based on retention times of 1 sec and 0.5 sec,

respectively Id. ( section 2.1 )

Kiln operation

Ceramic tile 980 1,200 1,800 2,200 Stay at or above temperature operating limit

established during performance test to maximize

D/F destruction Abraczinskas and Marinshaw,

1999 ( section IV.A

, Table 10 )

Sanitaryware 950 1,260 1,750 2,300 Id. ( section IV.B )

Spray dryer operation 70 570 160 1

, 050 Stay at or above temp erature operating limit

established during performance test to minimize

D/F formation Id. ( section IV.A )

Press d ryer operation

Ceramic tile 40 260 100 500 Stay at or below temperature operating limit

established during performance test to minimize

D/F formation Id. ( section IV.A )

Sanitaryware 60 100 140 210 Id. ( section IV.B )

## 8 Table 3 . Estimated Costs for Bag Leak Detection for Clay Ceramics Sources Equipped with Fabric Filters ( Baghouses ) 1 ,2



### Cost element Labor Test ODCs Total cost, 2007$ Total cost, 2011$

First c osts , $

Planning $1,462 $0 $352 $1,814

Select e quipment $6,346 $0 $643 $6,989

Support f acilities $0 $0 $1,030 $1,030

Purchase BLD system h ardware $0 $0 $18,232 $18,232

Install and c heck BLD system $161 $0 $5,022 $5,184

QA/QC Plan $739 $0 $0 $739

Total first c osts $8,708 $0 $25,280 $33,987 $37,888

Annual c osts , $/yr

Day

- to

- d ay a ctivities $2,822 $0 $0 $2,822 $2,822

Recordkeeping and r eporting $254 $0 $0 $254 $254

Annual QA & O&M r eview and u pdate $384 $0 $3,490 $3,874 $3,874

Capital r ecovery $1,240 $0 $3,600 $4,840 $5,394

Total with capital recovery $4,701 $0 $7,090 $11,791 $12,345

1 Reference: EPA, 2007. Updated to 2011 dollars using CEPCI.

2 ODC = other direct cost; QA/QC = quality assurance/quality control; O& M = operation and maintenance; and CEMS = continuous emission monitoring system

. .



### Cost year CEPCI 1

2007 525.4

2011 585.7

1 Reference: CE, 201 2

.

## 9 Table 4 . Estimated Costs for Periodic VE Monitoring of Clay Ceramics Sources 1



### Cost element Labor rates,

$/hr 2 

### Estimated costs, 2011$

First 30 days Rest of year Annual

Annual c osts, $/yr

Conduct 15

- minute VE check 3 $ 48 $ 360 $ 574 $ 934

Prepare for and document

Technical $ 48 $ 360 $ 574 $ 934

Management 4 $ 88 $ 33 $ 53 $ 86

Clerical 5 $ 28 $ 21 $ 34 $ 55

Training every 5 years 6 $ 976 $ 976

Total annual cost $ 1,750 $ 1,235 $ 2,984

1 Reference: Shrager, 2003.

2 Unloaded labor rates from BLS ( 201 2 )

. Technical labor rate based on mean hourly wage for Industrial Engineering

Technicians. Management labor rate based on mean hourly wage for Industrial Production Managers. Clerical labor

rate based on mean hourly wage for Office Clerks, General. Labor rates have been increased by 110 percent ( % ) to

include overhead.

3 Perform daily 15

- minute Method 22 VE check . Can reduce frequency to weekly for rest of year after 30 days with no

VE.

4 Assumed to be 5% of technical.

5 Assumed to be 10% of technical.

6 Assumes $2,000 per training course for two pe ople ($2,000 each), amortized over 5 years at 7% interest rate.



### Table 5 . Summary of Monitoring and Test ing Costs for Affected Clay Ceramics Facilities

Facility Affected source

type No. of

stacks Pollutants tested Test

cost, $ Annualized

test cost,

$/yr 1 

### Annual

monitoring

cost, $/yr

Kohler

Spartanburg Kiln 4 HF, HCl, PM, Hg, D/F $52,350 $12,770 $11,937

Glaze spray booth 8 PM

Kohler

Brownwood Kiln 1 HF, HCl, PM, Hg, D/F $19,140 $4,670 $2,984

Glaze spray booth 10 PM

Kohler

Wisconsin Kiln 2 HF, HCl, PM, Hg, D/F $30,510 $7,440 $5,969

Glaze spray booth 9 PM

Total $102,000 $24,880 $20,890

1 Annualized cost based on 7% interest, 5

- yr period.

## A ttachment A

Estimated Costs of Emission Tests for Each Affected Clay Ceramics Facility

## A

- 2 Table A

- 1 . Estimated Cost of Emission Test

– Kohler

- Spartanburg, SC

Parameter Value Assumptions

Hours of testing 48 Assumes M5, 3 runs, 1 hour each; M29, 3 runs, 1 hour each;

M26A, 3 runs, 1 hour each; M23, 3 runs, 2 hours each

No. of tests

Method 5

– PM 8 8 glaze spray booth stacks

Method 26A

- HF/HCl 4 4 kiln stacks

Method 29

- Metals 4 4 kiln stacks; includes metals and PM testing

Method 23

– D/F 4 4 kiln stacks

Total No. of tests 20

Days 8 8 hours of test runs per day, plus 1.5 days for setup and teardown

Nights 7

Travel time to site (hours) 4

Item/Activity Cost Assumptions

Equipment rental

V olumetric flow sampler 400

CO 2 /O 2 analyzer 1,600

Sample lines 600

Trailer to haul equipment 1,600

Rental truck 800

Miscellaneous equipment 2,400

Total equipment rental cost 7,400

Travel

L abor 1,160

L odging 1,575

P er diem 120

V ehicle rental 480 One car

Total travel cost 3,335

Testing cost

Mobilization 460 4 hours for site manager and Technician II

S etup equipment 580 Assume 4 hours for 3

- man crew

Perform test 9,257 Includes downtime, assumed to be 33% of testing time

T ake down equipment 290 Assume 2 hours for 3

- man crew

O nsite contingency 529 Approximately 5% of testing cost for short

- term delays

Total testing cost 11,116

Laboratory a nalysis

Method 5

- PM 1,080

Method 26A

- HF/HCl 2,000

Method 29

- Metals 10,600

Method 23

– D/F 12,480

Total 26,160

Test report

Data reduction and review 1,680 2 hr + 2 hr/test

Report preparation 1,240 2 hr + 1 hr/test for technical reviewer; 8 hr + 0.5 hr/test for clerical

Report review 1,320 1 hr + 0.5 hr/test for project manager

Supplies (paper, copies, etc.) 100 Assume $100

Total test report cost 4,340

SUMMARY

Total equipment rental cost 7,400

Total travel cost 3,335

Total testing cost 11,116

Laboratory analysis cost 26,160

Total test report cost 4,340

TOTAL 52,350

## A

- 3 Table A

- 2 . Estimated Cost of Emission Test

– Kohler

- Brownwood, TX

Parameter Value Assumptions

Hours of testing 1 2 Assumes M5, 3 runs, 1 hour each; M29, 3 runs, 1 hour each;

M26A, 3 runs, 1 hour each; M23, 3 runs, 2 hours each

No. of tests

Method 5

- PM 10 10 glaze spray booth stacks

Method 26A

- HF/HCl 1 1 kiln stack

Method 29

- Metals 1 1 kiln stack ; includes metals and PM testing

Method 23

– D/F 1 1 kiln stack

Total No. of tests 13

Days 3 8 hours of test runs per day, plus 1.5 days for setup and teardown

Nights 2

Travel time to site (hours) 4

Item/Activity Cost Assumptions

Equipment rental

V olumetric flow sampler 150

CO 2 /O 2 analyzer 600

Sample lines 225

Trailer to haul equipment 600

Rental truck 300

Miscellaneous equipment 900

Total equipment rental cost 2,775

Travel

L abor 1,160

L odging 450

P er diem 120

V ehicle rental 180 One car

Total travel cost 1,910

Testing cost

Mobilization 460 4 hours for site manager and Technician II

S etup equipment 580 Assume 4 hours for 3

- man crew

Perform test 2,314 Includes downtime, assumed to be 33% of testing time

T ake down equipment 290 Assume 2 hours for 3

- man crew

O nsite contingency 182 Approximately 5% of testing cost for short

- term delays

Total testing cost 3,826

Laboratory a nalysis

Method 5

- PM 1,350

Method 26A

- HF/HCl 500

Method 29

- Metals 2

, 6 50

Method 23

– D/F 3,120

Total 7,620

Test report

Data reduction and review 1,120 2 hr + 2 hr/test

Report preparation 890 2 hr + 1 hr/test for technical reviewer; 8 hr + 0.5 hr/test for clerical

Report review 900 1 hr + 0.5 hr/test for project manager

Supplies (paper, copies, etc.) 100 Assume $100

Total test report cost 3,010

SUMMARY

Total equipment rental cost 2,775

Total travel cost 1,910

Total testing cost 3,826

Laboratory analysis cost 7,620

Total test report cost 3,010

TOTAL 19,140

## A

- 4 Table A

- 3 . Estimated Cost of Emission Test

– Kohler

- Kohler

- WI

Parameter Value Assumptions

Hours of testing 24 Assumes M5, 3 runs, 1 hour each; M29, 3 runs, 1 hour each;

M26A, 3 runs, 1 hour each; M23, 3 runs, 2 hours each

No. of tests

Method 5

- PM 9 9 glaze spray booth stacks

Method 26A

- HF/HCl 2 2 kiln stack s

Method 29

- Metals 2 2 kiln stack s ; includes metals and PM testing

Method 23 2 2 kiln stacks

Total No. of tests 15

Days 5 8 hours of test runs per day, plus 1.5 days for setup and teardown

Nights 4

Travel time to site (hours) 4

Item/Activity Cost Assumptions

Equipment rental

V olumetric flow sampler 250

CO 2 /O 2 analyzer 1,000

Sample lines 375

Trailer to haul equipment 1,000

Rental truck 500

Miscellaneous equipment 1,500

Total equipment rental cost 4,625

Travel

L abor 1,160

L odging 900

P er diem 120

V ehicle rental 300 One car

Total travel cost 2,480

Testing cost

Mobilization 460 4 hours for site manager and Technician II

S etup equipment 580 Assume 4 hours for 3

- man crew

Perform test 4,628 Includes downtime, assumed to be 33% of testing time

T ake down equipment 290 Assume 2 hours for 3

- man crew

O nsite contingency 298 Approximately 5% of testing cost for short

- term delays

Total testing cost 6,256

Laboratory a nalysis

Method 5

- PM 1,215

Method 26A

- HF/HCl 1 ,0 00

Method 29

- Metals 5

, 3 0 0

Method 23

– D/F 6,240

Total 13,755

Test report

Data reduction and review 1,280 2 hr + 2 hr/test

Report preparation 990 2 hr + 1 hr/test for technical reviewer; 8 hr + 0.5 hr/test for clerical

Report review 1,020 1 hr + 0.5 hr/test for project manager

Supplies (paper, copies, etc.) 100 Assume $100

Total test report cost 3,390

SUMMARY

Total equipment rental cost 4,62 5

Total travel cost 2,48 0

Total testing cost 6 ,256

Laboratory analysis cost 1 3

, 755

Total test report cost 3,39 0

TOTAL 30

, 51 0

## Attachment B

Basic Rates and Analytical Costs

## B

- 2 Table B

- 1. Basic Rates for Labor, Per Diem, and Equipment Rental and Analytical Costs 1



### Daily expenses $/day

Lodging 75

Per diem 40

Vehicle rental 60

Volumetric flow sampler 50

CO 2 /O 2 analyzer 200

CO analyzer 200

NO x analyzer 200

SO 2 analyzer 200

FID/GC 400

Sample lines 75

Trailer to haul equipment 200

Rental truck 100

Miscellaneous equipment 300



### Labor rates (loaded) $/hr

Onsite testing staff:

Site manager 75

Technician II 40

Technician I 30

Office staff:

Project manager 120

Technical reviewer 40

Clerical 20

Financial 50



### Method Analytes Cost, $ Notes

5 PM 135 $45 per run, 3 runs

23 D/F 3,120 $1,040 per run, 3 runs

26A Acid gases 500 $50/analyte, 3 runs + 2 blanks

29 Metals 2,650 $530 per run, 3 runs + 2 blanks

1 CO 2 = carbon dioxide; O 2 = oxygen; CO = carbon monoxide; NOx = nitrogen oxides;

SO 2 = sulfur dioxide; FID/GC = flame ionization detector/gas chromatograph.