Page 1 of 25

Subpart Q—Iron and Steel Production

The iron and steel production source category includes 

facilities with any of the following processes: taconite iron 

ore processing, integrated iron and steel manufacturing, 

cokemaking not colocated with an integrated iron and steel 

manufacturing process, direct reduction furnaces not collocated 

with an integrated iron and steel manufacturing process, and 

electric arc furnace (EAF) steelmaking not colocated with an 

integrated iron and steel manufacturing process. Integrated iron 

and steel manufacturing means the production of steel from iron 

ore or iron ore pellets. At a minimum, an integrated iron and 

steel manufacturing process has a basic oxygen furnace for 

refining molten iron into steel. Each cokemaking process and EAF 

process located at a facility with an integrated iron and steel 

manufacturing process is part of the integrated iron and steel 

manufacturing facility.

§ 98.170 Definition of the source category.

You must report GHG emissions under this subpart if your 

facility contains an iron and steel production process and the 

facility meets the requirements of either §98.2(a)(1) or (2).

§ 98.171 Reporting threshold.

(a) You must report under subpart C of this part (General 

Stationary Fuel Combustion Sources) the emissions of CO

§ 98.172 GHGs to report.

2,CH4, and 
Page 2 of 25

N2

(b) You must report CO

O from each stationary combustion unit following the 

requirements of subpart C except for flares. Stationary 

combustion units include, but are not limited to, by-product 

recovery coke oven battery combustion stacks, blast furnace 

stoves, boilers, process heaters, reheat furnaces, annealing 

furnaces, flame suppression, ladle reheaters, and other 

miscellaneous combustion sources.

2 emissions from flares that burn 

blast furnace gas or coke oven gas according to the procedures 

in §98.253(b)(1) of subpart Y (Petroleum Refineries) of this 

part. When using the alternatives set forth in 

§98.253(b)(1)(ii)(B) and §98.253(b)(1)(iii)(C), you must use the 

default CO2 emission factors for coke oven gas and blast furnace 

gas from Table C–1 to subpart C in Equations Y–2 and Y–3 of 

subpart Y. You must report CH4 and N2

(c) You must report process CO

O emissions from flares 

according to the requirements in §98.33(c)(2) using the emission 

factors for coke oven gas and blast furnace gas in Table C–2 to 

subpart C of this part.

2 emissions from each taconite 

indurating furnace; basic oxygen furnace; non-recovery coke oven 

battery combustion stack; coke pushing process; sinter process; 

EAF; decarburization vessel; and direct reduction furnace by 

following the procedures in this subpart.

§ 98.173 Calculating GHG emissions.
Page 3 of 25

You must calculate and report the annual process CO2

emissions from each taconite indurating furnace, basic oxygen 

furnace, non-recovery coke oven battery, sinter process, EAF, 

decarburization vessel, and direct reduction furnace using the 

procedures in either paragraph (a) or (b) of this section. 

Calculate and report the annual process CO2

(a) Calculate and report under this subpart the process CO

emissions from the 

coke pushing process according to paragraph (c) of this section.

2

(b) Calculate and report under this subpart the process CO

emissions by operating and maintaining CEMS according to the 

Tier 4 Calculation Methodology in §98.33(a)(4) and all 

associated requirements for Tier 4 in subpart C of this part 

(General Stationary Fuel Combustion Sources).

2

(1) 

emissions using the procedure in paragraph (b)(1) or (b)(2) of 

this section.

Carbon mass balance method. Calculate the annual mass 

emissions of CO2 for the process as specified in paragraphs 

(b)(1)(i) through (b)(1)(vii) of this section. The calculations 

are based on the annual mass of inputs and outputs to the 

process and an annual analysis of the respective weight fraction 

of carbon as determined according to the procedures in 

§98.174(b). If you have a process input or output other than CO2

in the exhaust gas that contains carbon that is not included in 

Equations Q–1 through Q–7 of this section, you must account for 
Page 4 of 25

the carbon and mass rate of that process input or output in your 

calculations according to the procedures in §98.174(b)(5).

(i) For taconite indurating furnaces, estimate CO2 emissions 

using Equation Q–1 of this section.

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the taconite 

indurating furnace (metric tons).

2

(F

to carbon.

s

(C

) = Annual mass of the solid fuel combustedused

(metric tons).

sf) = Carbon content of the solid fuel, from the 

fuel analysis (percent by weight, expressed as 

a decimal fraction, e.g.

(F

, 95% = 0.95).

g

(C

) = Annual volume of the gaseous fuel 

combustedused (scf).

gf

MW = Molecular weight of the gaseous fuel (kg/kgmole).

) = Average carbon content of the gaseous fuel, 

from the fuel analysis results (kg C per kg of 

fuel).

MVC = Molar volume conversion factor (849.5 scf per 

kg-mole at standard conditions).

0.001 = Conversion factor from kg to metric tons.

(Fl

(C

) = Annual volume of the liquid fuel combustedused

(gallons).

lf

(O) = Annual mass of greenball (taconite) pellets 

fed to the furnace (metric tons).

) = Carbon content of the liquid fuel, from the 

fuel analysis results (kg C per gallon of 

fuel).

(C0) = Carbon content of the greenball (taconite) 

pellets, from the carbon analysis results 
Page 5 of 25

(percent by weight, expressed as a decimal 

fraction).

(P) = Annual mass of fired pellets produced by the 

furnace (metric tons).

(Cp

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the fired pellets, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

(CR

(ii) For basic oxygen process furnaces, estimate CO

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

2

emissions using Equation Q–2 of this section.

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the basic oxygen 

furnace (metric tons).

2

(Iron) = Annual mass of molten iron charged to the 

furnace (metric tons).

to carbon.

(CIron

(Scrap) = Annual mass of ferrous scrap charged to the 

furnace (metric tons).

) = Carbon content of the molten iron, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

(CScrap

(Flux) = Annual mass of flux materials (

) = Carbon content of the ferrous scrap, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

e.g., 

limestone, dolomite) charged to the furnace 

(metric tons).
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(CFlux

(Carbon) = Annual mass of carbonaceous materials (

) = Carbon content of the flux materials, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

e.g.

(C

, 

coal, coke) charged to the furnace (metric 

tons).

Carbon

(Steel) = Annual mass of molten raw steel produced by 

the furnace (metric tons).

) = Carbon content of the carbonaceous materials, 

from the carbon analysis results (percent by 

weight, expressed as a decimal fraction).

(CSteel

(Slag) = Annual mass of slag produced by the furnace 

(metric tons).

) = Carbon content of the steel, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CSlag

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the slag, from the carbon 

analysis (percent by weight, expressed as a 

decimal fraction).

(CR

(iii) For non-recovery coke oven batteries, estimate CO

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

2

emissions using Equation Q–3 of this section.

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the non-recovery 

coke oven battery (metric tons).

2

(Coal) = Annual mass of coal charged to the battery 

(metric tons).

to carbon.
Page 7 of 25

(CCoal

(Coke) = Annual mass of coke produced by the battery 

(metric tons).

) = Carbon content of the coal, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CCoke

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the coke, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CR

(iv) For sinter processes, estimate CO

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

2 emissions using 

Equation Q–4 of this section.

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the sinter 

process (metric tons).

2

(F

to carbon.

g

(C

) = Annual volume of the gaseous fuel 

combustedused (scf).

gf

MW = Molecular weight of the gaseous fuel (kg/kgmole).

) = Carbon content of the gaseous fuel, from the 

fuel analysis results (kg C per kg of fuel).

MVC = Molar volume conversion factor (849.5 scf per 

kg-mole at standard conditions).

0.001 = Conversion factor from kg to metric tons.

(Feed) = Annual mass of sinter feed material (metric 

tons).

(CFeed) = Carbon content of the mixed sinter feed 

materials that form the bed entering the 
Page 8 of 25

sintering machine, from the carbon analysis 

results (percent by weight, expressed as a

decimal fraction).

(Sinter) = Annual mass of sinter produced (metric tons).

(CSinter

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the sinter pellets, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

(CR

(v) For EAFs, estimate CO

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

2 emissions using Equation Q–5 of 

this section.

CO2 = 44

12 ∗ �(Iron) ∗ (CIron) + (Scrap) ∗ �CScrap� + (Flux) ∗ (CFlux) + (Electrode) ∗ (CElectrode) + (Carbon)

∗ (CCarbon) − (Steel) ∗ (CSteel) + �Fg� ∗ �Cgf� ∗ MW

MVC ∗ 0.001 − (Slag) ∗ �CSlag� − (R) ∗ (CR)�

(Eq. Q-5)

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the EAF (metric 

tons).

2

(Iron) = Annual mass of direct reduced iron (if any) 

charged to the furnace (metric tons).

to carbon.

(CIron

(Scrap) = Annual mass of ferrous scrap charged to the 

furnace (metric tons).

) = Carbon content of the direct reduced iron, 

from the carbon analysis results (percent by 

weight, expressed as a decimal fraction).

Formatted: Font: (Default) Arial, 9 pt
Page 9 of 25

(CScrap

(Flux) = Annual mass of flux materials (

) = Carbon content of the ferrous scrap, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

e.g.

(C

, 

limestone, dolomite) charged to the furnace 

(metric tons).

Flux

(Electrode) = Annual mass of carbon electrode consumed 

(metric tons).

) = Carbon content of the flux materials, from the 

carbon analysis results (percent by weight, 

expressed as a decimal fraction).

(CElectrode

(Carbon) = Annual mass of carbonaceous materials (

) = Carbon content of the carbon electrode, from 

the carbon analysis results (percent by 

weight, expressed as a decimal fraction).

e.g.

(C

, 

coal, coke) charged to the furnace (metric 

tons).

Carbon

(Steel) = Annual mass of molten raw steel produced by 

the furnace (metric tons).

) = Carbon content of the carbonaceous materials, 

from the carbon analysis results (percent by 

weight, expressed as a decimal fraction).

(CSteel

(F

) = Carbon content of the steel, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

g

(C

) = Annual volume of the gaseous fuel used (scf at 

60 degrees F and one atmosphere).

gf

(MW) = Molecular weight of the gaseous fuel (kg/kgmole).

) = Average carbon content of the gaseous fuel, 

from the fuel analysis results (kg C per kg of 

fuel).

(MVC) = Molar volume conversion factor (836.6 scf per 

kg-mole at standard conditions of 60 degrees F 

and one atmosphere).

(0.001) = Conversion factor from kg to metric tons.

(Slag) = Annual mass of slag produced by the furnace 

(metric tons).
Page 10 of 25

(CSlag

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the slag, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CR

(vi) For decarburization vessels, estimate CO

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

2 emissions 

using Equation Q–6 of this section.

CO2 = 44

12 ∗ {(Steel) ∗ [(CSteelin) − (CSteelout )] − (R) ∗ (CR)} (Eq. Q-6)

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the 

decarburization vessel (metric tons).

2

(Steel) = Annual mass of molten steel charged to the 

vessel (metric tons).

to carbon.

(CSteelin

(C

) = Carbon content of the molten steel before 

decarburization, from the carbon analysis 

results (percent by weight, expressed as a 

decimal fraction).

Steelout

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the molten steel after 

decarburization, from the carbon analysis 

results (percent by weight, expressed as a 

decimal fraction).

(CR) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

Formatted: Font: (Default) Arial, 9 pt
Page 11 of 25

(vii) For direct reduction furnaces, estimate CO2 emissions 

using Equation Q–7 of this section.

Where:

CO2 = Annual CO2

44/12 = Ratio of molecular weights, CO

mass emissions from the direct 

reduction furnace (metric tons).

2

(F

to carbon.

g

(C

) = Annual volume of the gaseous fuel 

combustedused (scf).

gf

MW = Molecular weight of the gaseous fuel (kg/kgmole).

) = Carbon content of the gaseous fuel, from the 

fuel analysis results (kg C per kg of fuel).

MVC = Molar volume conversion factor (849.5 scf per 

kg-mole at standard conditions).

0.001 = Conversion factor from kg to metric tons.

(Ore) = Annual mass of iron ore or iron ore pellets 

fed to the furnace (metric tons).

(COre

(Carbon) = Annual mass of carbonaceous materials (

) = Carbon content of the iron ore or iron ore 

pellets, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

e.g.

(C

, 

coal, coke) charged to the furnace (metric 

tons).

Carbon

(Other) = Annual mass of other materials charged to the 

furnace (metric tons).

) = Carbon content of the carbonaceous materials, 

from the carbon analysis results (percent by 

weight, expressed as a decimal fraction).
Page 12 of 25

(COther

(Iron) = Annual mass of iron produced (metric tons).

) = Average carbon content of the other materials 

charged to the furnace, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CIron

(NM) = Annual mass of non-metallic materials produced 

by the furnace (metric tons).

) = Carbon content of the iron, from the carbon 

analysis results (percent by weight, expressed 

as a decimal fraction).

(CNM

(R) = Annual mass of air pollution control residue 

collected (metric tons).

) = Carbon content of the non-metallic materials, 

from the carbon analysis results (percent by 

weight, expressed as a decimal fraction).

(CR

(2) 

) = Carbon content of the air pollution control 

residue, from the carbon analysis results 

(percent by weight, expressed as a decimal 

fraction).

Site-specific emission factor method. Conduct a 

performance test and measure CO2

(i) You must measure the process production rate or process 

feed rate, as applicable, during the performance test according 

to the procedures in §98.174(c)(5) and calculate the average 

rate for the test period in metric tons per hour.

emissions from all exhaust 

stacks for the process and measure either the feed rate of 

materials into the process or the production rate during the 

test as described in paragraphs (b)(2)(i) through (b)(2)(iv) of 

this section.
Page 13 of 25

(ii) You must calculate the hourly CO2 emission rate using 

Equation Q–8 of this section and determine the average hourly CO2

emission rate for the test.

Where:

CO2 = CO2

5.18 × 10−7 = Conversion factor (metric tons/scf−% CO

mass emission rate, corrected for moisture 

(metric tons/hr).

2

CCO

).

2 = Hourly CO2 concentration, dry basis (% CO2

Q = Hourly stack gas volumetric flow rate (scfh).

).

%H2

(iii) You must calculate a site-specific emission factor 

for the process in metric tons of CO

O = Hourly moisture percentage in the stack gas.

2 per metric ton of feed or 

production, as applicable, by dividing the average hourly CO2

(iv) You must calculate CO

emission rate during the test by the average hourly feed or 

production rate during the test.

2

(c) You must determine emissions of CO

emissions for the process by 

multiplying the emission factor by the total amount of feed or 

production, as applicable, for the reporting period.

2 from the coke 

pushing process in mtCO2e by multiplying the metric tons of coal 

charged to the by-product recovery and non-recovery coke ovens 

during the reporting period by 0.008.
Page 14 of 25

(d)If GHG emissions from a taconite indurating furnace, 

basic oxygen furnace, non-recovery coke oven battery, sinter 

process, EAF, decarburization vessel, or direct reduction 

furnace are vented through a stack equipped with a CEMS that 

complies with the Tier 4 methodology in subpart C of this part, 

or through the same stack as any combustion unit or process 

equipment that reports CO2 emissions using a CEMS that complies 

with the Tier 4 Calculation Methodology in subpart C of this 

part (General Stationary Fuel Combustion Sources), then the 

calculation methodology in paragraph (b) of this section shall 

not be used to calculate process emissions. The owner or 

operator shall report under this subpart the combined stack 

emissions according to the Tier 4 Calculation Methodology in 

§98.33(a)(4) and comply with all associated requirements for 

Tier 4 in subpart C of this part (General Stationary Fuel 

Combustion Sources).

(a) If you operate and maintain a CEMS that measures CO

§ 98.174 Monitoring and QA/QC requirements.

2

(b) If you determine CO

emissions consistent with subpart C of this part, you must meet 

the monitoring and QA/QC requirements of §98.34(c).

2

(1) Except as provided in paragraph (b)(4) of this section, 

determine the mass of each process input and output other than 

emissions using the carbon mass 

balance procedure in §98.173(b)(1), you must:
Page 15 of 25

fuels using the same plant instruments or procedures that are 

used for accounting purposes (such as weigh hoppers, belt weigh 

feeders, weighed purchased quantities in shipments or 

containers, combination of bulk density and volume measurements, 

etc.), record the totals for each process input and output for 

each calendar month, and sum the monthly mass to determine the 

annual mass for each process input and output. Determine the 

mass rate of fuels using the procedures for combustion units in 

§98.34. No determination of the mass of steel output from

decarburization vessels is required. 

(2) Except as provided in paragraph (b)(4) of this section, 

determine the carbon content of each process input and output 

annually for use in the applicable equations in §98.173(b)(1) 

based on analyses provided by the supplier or by the average 

carbon content determined by collecting and analyzing at least 

three samples each year using the standard methods specified in 

paragraphs (b)(2)(i) through (b)(2)(vi) of this section as 

applicable.

(i) ASTM C25–06, Standard Test Methods for Chemical 

Analysis of Limestone, Quicklime, and Hydrated Lime 

(incorporated by reference, see §98.7) for limestone, dolomite, 

and slag.

(ii) ASTM D5373–08 Standard Test Methods for Instrumental 

Determination of Carbon, Hydrogen, and Nitrogen in Laboratory 
Page 16 of 25

Samples of Coal (incorporated by reference, see §98.7) for coal, 

coke, and other carbonaceous materials.

(iii) ASTM E1915–07a, Standard Test Methods for Analysis of 

Metal Bearing Ores and Related Materials by Combustion InfraredAbsorption Spectrometry (incorporated by reference, see §98.7) 

for iron ore, taconite pellets, and other iron-bearing 

materials.

(iv) ASTM E1019–08, Standard Test Methods for Determination 

of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, 

and Cobalt Alloys by Various Combustion and Fusion Techniques 

(incorporated by reference, see §98.7) for iron and ferrous 

scrap.

(v) ASM CS–104 UNS No. G10460—Alloy Digest April 1985 

(Carbon Steel of Medium Carbon Content) (incorporated by 

reference, see §98.7); ISO/TR 15349–1:1998, Unalloyed steel—

Determination of low carbon content, Part 1: Infrared absorption 

method after combustion in an electric resistance furnace (by 

peak separation) (1998–10–15) First Edition (incorporated by 

reference, see §98.7); or ISO/TR 15349–3:1998, Unalloyed steelDetermination of low carbon content Part 3: Infrared absorption 

method after combustion in an electric resistance furnace (with 

preheating) (1998–10–15) First Edition (incorporated by 

reference, see §98.7) as applicable for steel.
Page 17 of 25

(vi) For each process input that is a fuel, determine the 

carbon content and molecular weight (if applicable) using the 

applicable methods listed in §98.34.

(3) For solid ferrous materials charged to basic oxygen 

process furnaces or EAFs that differ in carbon content, you may 

determine a weighted average carbon content based on the carbon 

content of each type of ferrous material and the average weight 

percent of each type that is used. Examples of these different 

ferrous materials include carbon steel, low carbon steel, 

stainless steel, high alloy steel, pig iron, iron scrap, and 

direct reduced iron.

(4) If you document that a specific process input or output 

contributes less than one percent of the total mass of carbon 

into or out of the process, you do not have to determine the 

monthly mass or annual carbon content of that input or output.

(5) Except as provided in paragraph (b)(4) of this section, 

you must determine the annual carbon content and monthly mass 

rate of any input or output that contains carbon that is not 

listed in the equations in §98.173(b)(1) using the procedures in 

paragraphs (b)(1) and (b)(2) of this section.

(c) If you determine CO2 emissions using the site-specific 

emission factor procedure in §98.173(b)(2), you must:
Page 18 of 25

(1) Conduct an annual performance test that is based on 

representative performance (i.e.

(2))(i) For the furnace exhaust from basic oxygen furnaces, 

EAFs, decarburization vessels, and direct reduction furnaces, 

sample the furnace exhaust for at least three complete 

production cycles that start when the furnace is being charged 

and end after steel or iron and slag have been tapped. For EAFs 

that produce both carbon steel and stainless or specialty (low 

carbon) steel, develop an emission factor for the production of 

both types of steel.

, performance based on normal 

operating conditions) of the affected process.

(ii) For the exhaust from continuously charged EAFs, sample 

the exhaust for a period spanning at least three hours. For EAFs 

that produce both carbon steel and stainless or specialty (low 

carbon) steel, develop an emission factor for the production of 

both types of steel.

(3) For taconite indurating furnaces, non-recovery coke 

batteries, and sinter processes, sample for at least 3 hours.

(4) Conduct the stack test using EPA Method 3A at 40 CFR 

part 60, appendix A–2 to measure the CO2 concentration, Method 2, 

2A, 2C, 2D, or 2F at 40 CFR part 60, appendix A–1 or Method 26 

at 40 CFR part 60, appendix A–2 to determine the stack gas 

volumetric flow rate, and Method 4 at 40 CFR part 60, at 

appendix A–3 to determine the moisture content of the stack gas.
Page 19 of 25

(5) Determine the mass rate of process feed or process 

production (as applicable) during the test using the same plant 

instruments or procedures that are used for accounting purposes 

(such as weigh hoppers, belt weigh feeders, combination of bulk 

density and volume measurements, etc.)

(6) If your process operates under different conditions as 

part of normal operations in such a manner that CO2 emissions 

change by more than 20 percent (e.g.

(7) If your EAF and decarburization vessel exhaust to a 

common emission control device and stack, you must sample each 

process in the ducts before the emissions are combined, sample 

each process when only one process is operating, or sample the 

combined emissions when both processes are operating and base 

the site-specific emission factor on the steel production rate 

of the EAF.

, routine changes in the 

carbon content of the sinter feed or change in grade of 

product), you must perform emission testing and develop separate 

emission factors for these different operating conditions and 

determine emissions based on the number of hours the process 

operates and the production or feed rate (as applicable) at each 

specific different condition.

(8) The results of a performance test must include the 

analysis of samples, determination of emissions, and raw data. 
Page 20 of 25

The performance test report must contain all information and 

data used to derive the emission factor.

(d) For a coke pushing process, determine the metric tons 

of coal charged to the coke ovens and record the totals for each 

pushing process for each calendar month. Coal charged to coke 

ovens can be measured using weigh belts or a combination of 

measuring volume and bulk density.

A complete record of all measured parameters used in the 

GHG emissions calculations in §98.173 is required. Therefore, 

whenever a quality-assured value of a required parameter is 

unavailable, a substitute data value for the missing parameter 

shall be used in the calculations as specified in the paragraphs 

(a) and (b) of this section. You must follow the missing data 

procedures in §98.255(b) of subpart Y (Petroleum Refineries) of 

this part for flares burning coke oven gas or blast furnace gas. 

You must document and keep records of the procedures used for 

all such estimates.

§ 98.175 Procedures for estimating missing data.

(a) For each missing data Except as provided in 

§98.174(b)(4), 100 percent data availability is required for the 

carbon content of inputs and outputs for facilities that 

estimate emissions using the carbon mass balance procedure in 

§98.173(b)(1) or for facilities that estimate emissions using 

the site-specific emission factor procedure in §98.173(b)(2); 
Page 21 of 25

100 percent data availability is required. You must repeat the 

test for average carbon contents of inputs and outputs according 

to the procedures in §98.174(b)(2). Similarly, you must repeat 

the test to determine the site-specific emission factor if data 

on the CO2

(b) For missing records of the monthly mass or volume of 

carbon-containing inputs and outputs using the carbon mass 

balance procedure in §98.173(b)(1), the substitute data value 

must be based on the best available estimate of the mass of the 

input or output material from all available process data or data 

used for accounting purposes.

emission rate, process production rate or process feed 

rate are missing.). 

In addition to the information required by §98.3(c), each 

annual report must contain the information required in 

paragraphs (a) through (h) of this section for each coke pushing 

operation; taconite indurating furnace; basic oxygen furnace; 

non-recovery coke oven battery; sinter process; EAF; 

decarburization vessel; direct reduction furnace; and flare 

burning coke oven gas or blast furnace gas. For reporting year 

2010, the information required in paragraphs (a) through (h) of 

this section is not required for decarburization vessels that 

are not argon-oxygen decarburization vessels. For reporting year 

2011 and each subsequent reporting year, the information in 

§ 98.176 Data reporting requirements.
Page 22 of 25

paragraphs (a) through (h) of this section must be reported for 

all decarburization vessels.

(a) Unit identification number and annual CO2

(b) Annual production quantity (in metric tons) for 

taconite pellets, coke, sinter, iron, and raw steel.

emissions (in 

metric tons).

(c) If a CEMS is used to measure CO2

(d) If a CEMS is not used to measure CO

emissions, then you 

must report the relevant information required under §98.36 for 

the Tier 4 Calculation Methodology.

2

(e) If you use the carbon mass balance method in 

§98.173(b)(1) to determine CO

emissions, then you 

must report for each process whether the emissions were 

determined using the carbon mass balance method in §98.173(b)(1) 

or the site-specific emission factor method in §98.173(b)(2).

2

(1) The carbon content of each process input and output 

used to determine CO

emissions, you must, except as 

provided in §98.174(b)(4), report the following information for 

each process:

2

(2) Whether the carbon content was determined from 

information from the supplier or by laboratory analysis, and if 

by laboratory analysis, the method used.

emissions.

(3) The annual volume of each type of gaseous fuel 

(reported separately for each type in standard cubic feet), the 
Page 23 of 25

annual volume of each type of liquid fuel (reported separately 

for each type in gallons), and the annual mass (in metric tons) 

of each other process inputs and outputs used to determine CO2

(4) The molecular weight of gaseous fuels.

emissions.

(5) If you used the missing data procedures in §98.175(b), 

you must report how the monthly mass for each process input or 

output with missing data was determined and the number of months 

the missing data procedures were used.

(f) If you used the site-specific emission factor method in 

§98.173(b)(2) to determine CO2

(1) The measured average hourly CO

emissions, you must report the 

following information for each process:

2

(2) The average hourly feed or production rate (as 

applicable) during the test (in metric tons per hour).

emission rate during the 

test (in metric tons per hour).

(3) The site-specific emission factor (in metric tons of CO2

(4) The annual feed or production rate (as applicable) used 

to estimate annual CO

per metric ton of feed or production, as applicable).

2

(g) The annual amount of coal charged to the coke ovens (in 

metric tons).

emissions (in metric tons).
Page 24 of 25

(h) For flares burning coke oven gas or blast furnace gas, 

the information specified in §98.256(e) of subpart Y (Petroleum 

Refineries) of this part.

In addition to the records required by §98.3(g), you must 

retain the records specified in paragraphs (a) through (e) of 

this section, as applicable. Facilities that use CEMS to measure 

emissions must also retain records of the verification data 

required for the Tier 4 Calculating Methodology in §98.36(e).

§ 98.177 Records that must be retained.

(a) Records of all analyses and calculations conducted, 

including all information reported as required under §98.176.

(b) When the carbon mass balance method is used to estimate 

emissions for a process, the monthly mass of each process input 

and output that are used to determine the annual mass, except 

that no determination of the mass of steel output from

decarburization vessels is required.

(c) Production capacity (in metric tons per year) for the 

production of taconite pellets, coke, sinter, iron, and raw 

steel.

(d) Annual operating hours for each taconite indurating 

furnace, basic oxygen furnace, non-recovery coke oven battery, 

sinter process, electric arc furnace, decarburization vessel, 

and direct reduction furnace.
Page 25 of 25

(e) Facilities must keep records that include a detailed 

explanation of how company records or measurements are used to 

determine all sources of carbon input and output and the metric 

tons of coal charged to the coke ovens (e.g., weigh belts, a 

combination of measuring volume and bulk density). You also must 

document the procedures used to ensure the accuracy of the 

measurements of fuel usage including, but not limited to, 

calibration of weighing equipment, fuel flow meters, coal usage 

including, but not limited to, calibration of weighing equipment 

and other measurement devices. The estimated accuracy of 

measurements made with these devices must also be recorded, and 

the technical basis for these estimates must be provided.

All terms used in this subpart have the same meaning given 

in the Clean Air Act and subpart A of this part.

§ 98.178 Definitions.