January 12, 2004

APPENDIX B OF PART 60 - PERFORMANCE SPECIFICATIONS

* * * * *

PERFORMANCE SPECIFICATION 11 - Specifications and Test

Procedures for Particulate Matter 

Continuous Emission Monitoring Systems at

Stationary Sources

1.0 What are the purpose and applicability of Performance

Specification 11?

The purpose of Performance Specification 11 (PS-11) is to

establish the initial installation and performance procedures

that are required for evaluating the acceptability of a

particulate matter (PM) continuous emission monitoring system

(CEMS); it is not to evaluate the ongoing performance of your

PM CEMS over an extended period of time, nor to identify

specific calibration techniques and auxiliary procedures to

assess CEMS performance. You will find procedures for

evaluating the ongoing performance of a PM CEMS in Procedure 2

of Appendix F - Quality Assurance Requirements for Particulate

Matter Continuous Emission Monitoring Systems Used at

Stationary Sources.

1.1 Under what conditions does PS-11 apply to my PM

CEMS? The PS-11 applies to your PM CEMS if you are required

by any provision of Title 40 of the Code of Federal

Regulations (CFR) to install and operate PM CEMS. 

1.2 When must I comply with PS-11? You must comply with

PS-11 when directed by the applicable rule that requires you

to install and operate a PM CEMS.

1.3 What other monitoring must I perform? To report

your PM emissions in units of the emission standard, you may

need to monitor additional parameters to correct the PM

concentration reported by your PM CEMS. Your CEMS may include

the components listed in paragraphs (1) through (3) of this

section:

(1) A diluent monitor (i.e., O2, CO2, or other CEMS

specified in the applicable regulation), which must meet its

own performance specifications (also found in this appendix), 

(2) Auxiliary monitoring equipment to allow measurement,

determination, or input of the flue gas temperature, pressure,

moisture content, and/or dry volume of stack effluent sampled,

and 

(3) An automatic sampling system. 

The performance of your PM CEMS and the establishment of its

correlation to manual reference method measurements must be

determined in units of mass concentration as measured by your

PM CEMS (e.g., milligrams per actual cubic meter (mg/acm) or
milligrams per dry standard cubic meter (mg/dscm)).

2.0 What are the basic requirements of PS-11?

The PS-11 requires you to perform initial installation

and calibration procedures that confirm the acceptability of

your CEMS when it is installed and placed into operation. You

must develop a site-specific correlation of your PM CEMS

response against manual gravimetric reference method

measurements (including those made using EPA Methods 5, 5I, or

17). 

2.1 What types of PM CEMS technologies are covered? 

Several different types of PM CEMS technologies (e.g., light

scattering, Beta attenuation, etc.) can be designed with insitu or extractive sample gas handling systems. Each PM CEMS

technology and sample gas handling technology has certain

site-specific advantages. You should select and install a PM

CEMS that is appropriate for the flue gas conditions at your

source.

2.2 How is PS-11 different from other performance

specifications? The PS-11 is based on a technique of

correlating PM CEMS responses relative to emission

concentrations determined by the reference method. This

technique is called "the correlation." This differs from CEMS

used to measure gaseous pollutants that have available

calibration gases of known concentration. Because the type

and characteristics of PM vary from source to source, a single

PM correlation, applicable to all sources, is not possible.

2.3 How are the correlation data handled? You must

carefully review your manual reference method data and your PM

CEMS responses to include only valid, high-quality data. For

the correlation, you must convert the manual reference method

data to measurement conditions (e.g., wet or dry basis) that

are consistent with your PM CEMS. Then, you must correlate

the manual method and PM CEMS data in terms of the output as

received from the monitor (e.g., milliamps). At the

appropriate PM CEMS response specified in section 13.2 of this

performance specification, you must calculate the confidence

interval half range and tolerance interval half range as a

percentage of the applicable PM concentration emission limit

and compare the confidence interval and tolerance interval

percentages with the performance criteria. Also, you must

calculate the correlation coefficient and compare the

correlation coefficient with the applicable performance

criterion specified in section 13.2 of this performance

specification.

Situations may arise where you will need two or more

correlations. If you need multiple correlations, you must

collect sufficient data for each correlation, and each

correlation must satisfy the performance criteria specified in
section 13.2 of this performance specification.

2.4 How do I design my PM CEMS correlation program? 

When planning your PM CEMS correlation effort, you must

address each of the items in paragraphs (1) through (7) of

this section to enhance the probability of success. You will

find each of these elements further described in this

performance specification or in the applicable reference

method procedure.

(1) What type of PM CEMS should I select? You should

select a PM CEMS that is appropriate for your source with

technical consideration for potential factors such as

interferences, site-specific configurations, installation

location, flue gas conditions, PM concentration range, and

other PM characteristics. You can find guidance on which

technology is best suited for specific situations in our

report "Current Knowledge of Particulate Matter (PM)

Continuous Emission Monitoring" (PM CEMS Knowledge Document,

see section 16.5).

(2) Where should I install my PM CEMS? Your PM CEMS

must be installed in a location that is most representative of

PM emissions, as determined by the reference method, such that

the correlation between PM CEMS response and emissions

determined by the reference method will meet these performance

specifications. Care must be taken in selecting a location

and measurement point to minimize problems due to flow

disturbances, cyclonic flow, and varying PM stratification.

(3) How should I record my CEMS data? You need to

ensure that your PM CEMS and data logger are set up to collect

and record all normal emission levels and excursions. You

must ensure that your data logger and PM CEMS have been

properly programmed to accept and transfer status signals of

valid monitor operation (e.g., flags for internal calibration,

suspect data, or maintenance periods).

(4) What CEMS data should I review? You must review

drift data daily to document proper operation. You must also

ensure that any audit material is appropriate for the typical

operating range of your PM CEMS.

(5) How long should I operate my PM CEMS before

conducting the initial correlation test? You should allow

sufficient time for your PM CEMS to operate for you to become

familiar with your PM CEMS. 

(i) You should observe PM CEMS response over time during

normal and varying process conditions. This will ensure that

your PM CEMS has been properly set up to operate at a range

that is compatible with the concentrations and characteristics

of PM emissions for your source. You should use this

information to establish the range of operating conditions

necessary to determine the correlations of PM CEMS data to
manual reference method measurements over a wide operating

range. 

(ii) You must determine the types of process changes

that will influence, on a definable and repeatable basis, flue

gas PM concentrations and the resulting PM CEMS responses. 

You may find this period useful to make adjustments to your

planned approach for operating your PM CEMS at your source. 

For instance, you may change the measurement range or batch

sampling period to something other than those you initially

planned to use.

(6) How do I conduct the initial correlation test? 

When conducting the initial correlation test of your PM CEMS

response to PM emissions determined by the reference method,

you must pay close attention to accuracy and details. Your PM

CEMS must be operating properly. You must perform the manual

reference method testing accurately, with attention to

eliminating site-specific systemic errors. You must

coordinate the timing of the manual reference method testing

with the sampling cycle of your PM CEMS. You must complete a

minimum of 15 manual reference method tests. You must perform

the manual reference method testing over the full range of PM

CEMS responses that correspond to normal operating conditions

for your source and control device and will result in the

widest range of emission concentrations. 

(7) How should I perform the manual reference method

testing? You must perform the manual reference method testing

in accordance with specific rule requirements, coordinated

closely with PM CEMS and process operations. It is highly

recommended that you use paired trains for the manual

reference method testing. You must perform the manual

reference method testing over a suitable PM concentration

range that corresponds to the full range of normal process and

control device operating conditions. Because the manual

reference method testing for this correlation test is not for

compliance reporting purposes, you may conduct the reference

method test runs for less than the typical minimum test run

duration of 1 hour.

(8) What do I do with the manual reference method data

and PM CEMS data? You must complete each of the activities in

paragraphs (8)(i) through (v) of this section. 

(i) Screen the manual reference method data for validity

(e.g., isokinetics, leak checks), quality assurance, and

quality control (e.g., outlier identification).

(ii) Screen your PM CEMS data for validity (e.g., daily

drift check requirements) and quality assurance (e.g., flagged

data). 

(iii) Convert the manual reference method test data into

measurement units (e.g., mg/acm) consistent with the
measurement conditions of your PM CEMS.

(iv) Calculate the correlation equation(s) as specified

in section 12.3.

(v) Calculate the correlation coefficient, confidence

interval half range, and tolerance interval half range for the

complete set of PM CEMS and reference method correlation data

for comparison with the correlation performance criteria

specified in section 13.2.

2.5 What other procedures must I perform? Before

conducting the initial correlation test, you must successfully

complete a 7-day drift test (See section 8.5).

3.0 What special definitions apply to PS-11?

3.1 "Appropriate Measurement Range of your PM CEMS"

means a measurement range that is capable of recording

readings over the complete range of your source’s PM emission

concentrations during routine operations. The appropriate

range is determined during the pretest preparations as

specified in section 8.4.

3.2 "Appropriate Data Range for PM CEMS Correlation"

means the data range that reflects the full range of your

source’s PM emission concentrations recorded by your PM CEMS

during the correlation test planning period or other normal

operations as defined in the applicable regulations.

3.3 "Batch Sampling" means that gas is sampled on an

intermittent basis and concentrated on a collection medium

before intermittent analysis and follow-up reporting. Beta

gauge PM CEMS are an example of batch sampling devices.

3.4 "Confidence Interval Half Range (CI)" means the

statistical term for one-half of the width of the 95 percent

confidence interval around the predicated mean PM

concentration (y value) calculated at the PM CEMS response

value (x value) where the confidence interval is narrowest. 

Procedures for calculating CI are specified in section

12.3(1)(ii) for linear correlations and in section 12.3(2)(ii)

for polynomial correlations. The CI as a percent of the

emission limit value (CI%) is calculated at the appropriate PM

CEMS response value specified in Section 13.2(2).

3.5 "Continuous Emission Monitoring System (CEMS)" means

all of the equipment required for determination of PM mass

concentration in units of the emission standard. The sample

interface, pollutant monitor, diluent monitor, other auxiliary

data monitor(s), and data recorder are the major subsystems of

your CEMS.

3.6 "Correlation" means the primary mathematical

relationship for correlating the output from your PM CEMS to a

PM concentration, as determined by the PM reference method. 

The correlation is expressed in the measurement units that are
consistent with the measurement conditions (e.g., mg/dscm,

mg/acm) of your PM CEMS.

3.7 "Correlation Coefficient (r)" means a quantitative

measure of the association between your PM CEMS outputs and

the reference method measurements. Equations for calculating

the r value are provided in section 12.3(1)(iv) for linear

correlations and in section 12.3(2)(iv) for polynomial

correlations.

3.8 "Cycle Time" means the time required to complete one

sampling, measurement, and reporting cycle. For a batch

sampling PM CEMS, the cycle time would start when sample gas

is first extracted from the stack/duct and end when the

measurement of that batch sample is complete and a new result

for that batch sample is produced on the data recorder.

3.9 "Data Recorder" means the portion of your CEMS that

provides a permanent record of the monitor output in terms of

response and status (flags). The data recorder may also

provide automatic data reduction and CEMS control capabilities

(see section 6.6).

3.10 "Diluent Monitor and Other Auxiliary Data

Monitor(s) (if applicable)" means the portion of your CEMS

that provides the diluent gas concentration (such as O2 or CO2,

as specified by the applicable regulations), temperature,

pressure, and/or moisture content, and generates an output

proportional to the diluent gas concentration or gas property.

3.11 "Drift Check" means a check of the difference

between your PM CEMS output readings and the established

reference value of a reference standard or procedure after a

stated period of operation during which no unscheduled

maintenance, repair, or adjustment took place. The procedures

used to determine drift are specific to the operating

principles of your specific PM CEMS. A drift check includes

both a zero drift check and an upscale drift check.

3.12 "Exponential Correlation" means an exponential

equation used to define the relationship between your PM CEMS

output and the reference method PM concentration, as indicated

by Equation 11-37.

3.13 "Flagged Data" means data marked by your CEMS

indicating that the response value(s) from one or more CEMS

subsystems is suspect or invalid or that your PM CEMS is not

in source-measurement operating mode.

3.14 "Linear Correlation" means a first-order

mathematical relationship between your PM CEMS output and the

reference method PM concentration that is linear in form, as

indicated by Equation 11-3.

3.15 "Logarithmic Correlation" means a first-order

mathematical relationship between the natural logarithm of
your PM CEMS output and the reference method PM concentration

that is linear in form, as indicated by Equation 11-34.

3.16 "Low-Emitting Source" means a source that operated

at no more than 50 percent of the emission limit during the

most recent performance test, and, based on the PM CEMS

correlation, the daily average emissions for the source,

measured in the units of the applicable emission limit, have

not exceeded 50 percent of the emission limit for any day

since the most recent performance test.

3.17 "Paired Trains" means two reference method trains

that are used to conduct simultaneous measurements of PM

concentrations. Guidance on the use of paired sampling trains

can be found in the PM CEMS Knowledge Document (see section

16.5).

3.18 "Polynomial Correlation" means a second-order

equation used to define the relationship between your PM CEMS

output and reference method PM concentration, as indicated by

Equation 11-16.

3.19 "Power Correlation" means an equation used to

define a power function relationship between your PM CEMS

output and the reference method concentration, as indicated by

Equation 11-42.

3.20 "Reference Method" means the method defined in the

applicable regulations, but commonly refers to those methods

collectively known as EPA Methods 5, 5I, and 17 (for

particulate matter), found in Appendix A of 40 CFR 60. Only

the front half and dry filter catch portions of the reference

method can be correlated to your PM CEMS output.

3.21 "Reference Standard" means a reference material or

procedure that produces a known and unchanging response when

presented to the pollutant monitor portion of your CEMS. You

must use these standards to evaluate the overall operation of

your PM CEMS, but not to develop a PM CEMS correlation.

3.22 "Response Time" means the time interval between the

start of a step change in the system input and the time when

the pollutant monitor output reaches 95 percent of the final

value (see sections 6.5 and 13.3 for procedures and acceptance

criteria).

3.23 "Sample Interface" means the portion of your CEMS

used for one or more of the following: sample acquisition,

sample delivery, sample conditioning, or protection of the

monitor from the effects of the stack effluent.

3.24 "Sample Volume Check" means a check of the

difference between your PM CEMS sample volume reading and the

sample volume reference value. 

3.25 "Tolerance Interval half range (TI)" means one-half

of the width of the tolerance interval with upper and lower

limits, within which a specified percentage of the future data
population is contained with a given level of confidence, as

defined by the respective tolerance interval half range

equations in section 12.3(1)(iii) for linear correlations and

in section 12.3(2)(iii) for polynomial correlations. The TI

as a percent of the emission limit value (TI%) is calculated

at the appropriate PM CEMS response value specified in Section

13.2(3).

3.26 "Upscale Check Value" means the expected response

to a reference standard or procedure used to check the upscale

response of your PM CEMS.

3.27 "Upscale Drift (UD) Check" means a check of the

difference between your PM CEMS output reading and the upscale

check value. 

3.28 "Zero Check Value" means the expected response to a

reference standard or procedure used to check the response of

your PM CEMS to particulate-free or low-particulate

concentration conditions. 

3.29 "Zero Drift (ZD) Check" means a check of the

difference between your PM CEMS output reading and the zero

check value. 

3.30 "Zero Point Correlation Value" means a value added

to PM CEMS correlation data to represent low or near zero PM

concentration data (see section 8.6 for rationale and

procedures).

4.0 Are there any potential interferences for my PM CEMS?

Yes, condensible water droplets or condensible acid gas

aerosols (i.e., those with condensation temperatures above

those specified by the reference method) at the measurement

location can be interferences for your PM CEMS if the

necessary precautions are not met. 

4.1 Where are interferences likely to occur? 

Interferences may develop if your CEMS is installed downstream

of a wet air pollution control system or any other conditions

that produce flue gases, which, at your PM CEMS measurement

point, normally or occasionally contain entrained water

droplets or condensible salts before release to the

atmosphere. 

4.2 How do I deal with interferences? We recommend that

you use a PM CEMS that extracts and heats representative

samples of the flue gas for measurement to simulate results

produced by the reference method for conditions such as those

described in section 4.1. Independent of your PM CEMS

measurement technology and extractive technique, you should

have a configuration simulating the reference method to ensure

that: 

(1) No formation of new PM or deposition of PM occurs in

sample delivery from the stack or duct; and

(2) No condensate accumulates in the sample flow
measurement apparatus.

4.3 What PM CEMS measurement technologies should I use? 

You should use a PM CEMS measurement technology that is free

of interferences from any condensible constituent in the flue

gas.

5.0 What do I need to know to ensure the safety of persons

using PS-11?

People using the procedures required under PS-11 may be

exposed to hazardous materials, operations, site conditions,

and equipment. This performance specification does not

purport to address all of the safety issues associated with

its use. It is your responsibility to establish appropriate

safety and health practices and determine the applicable

regulatory limitations before performing these procedures. 

You must consult your CEMS user’s manual and other reference

materials recommended by the reference method for specific

precautions to be taken.

6.0 What equipment and supplies do I need?

Different types of PM CEMS use different operating

principles. You should select an appropriate PM CEMS based on

your site-specific configurations, flue gas conditions, and PM

characteristics. 

(1) Your PM CEMS must sample the stack effluent

continuously or, for batch sampling PM CEMS, intermittently. 

(2) You must ensure that the averaging time, the number

of measurements in an average, the minimum data availability,

and the averaging procedure for your CEMS conform with those

specified in the applicable emission regulation.

(3) Your PM CEMS must include, as a minimum, the

equipment described in sections 6.1 through 6.7. 

6.1 What equipment is needed for my PM CEMS’s sample

interface? Your PM CEMS’s sample interface must be capable of

delivering a representative sample of the flue gas to your PM

CEMS. This subsystem may be required to heat the sample gas

to avoid PM deposition or moisture condensation, provide

dilution air, perform other gas conditioning to prepare the

sample for analysis, or measure the sample volume or flow

rate. 

(1) If your PM CEMS is installed downstream of a wet air

pollution control system such that the flue gases normally or

occasionally contain entrained water droplets, we recommend

that you select a sampling system that includes equipment to

extract and heat a representative sample of the flue gas for

measurement so that the pollutant monitor portion of your CEMS

measures only dry PM. Heating should be sufficient to raise

the temperature of the extracted flue gas above the water

condensation temperature and should be maintained at all times

and at all points in the sample line from where the flue gas
is extracted, including the pollutant monitor and any sample

flow measurement devices.

(2) You must consider the measured conditions of the

sample gas stream to ensure that manual reference method test

data are converted to units of PM concentration that are

appropriate for the correlation calculations. Additionally,

you must identify what, if any, additional auxiliary data from

other monitoring and handling systems are necessary to convert

your PM CEMS response into the units of the PM standard.

(3) If your PM CEMS is an extractive type and your

source’s flue gas volumetric flow rate varies by more than 10

percent from nominal, your PM CEMS should maintain an

isokinetic sampling rate (within 10 percent of true

isokinetic). If your extractive-type PM CEMS does not

maintain an isokinetic sampling rate, you must use actual

site-specific data or data from a similar installation to

prove to us, the State, and/or local enforcement agency that

isokinetic sampling is not necessary.

6.2 What type of equipment is needed for my PM CEMS? 

Your PM CEMS must be capable of providing an electronic output

that can be correlated to the PM concentration.

(1) Your PM CEMS must be able to perform zero and

upscale drift checks. You may perform these checks manually,

but performing these checks automatically is preferred.

(2) We recommend that you select a PM CEMS that is

capable of performing automatic diagnostic checks and sending

instrument status signals (flags) to the data recorder.

(3) If your PM CEMS is an extractive type that measures

the sample volume and uses the measured sample volume as part

of calculating the output value, your PM CEMS must be able to

perform a check of the sample volume to verify the accuracy of

the sample volume measuring equipment. The sample volume

check must be conducted daily and at the normal sampling rate

of your PM CEMS.

6.3 What is the appropriate measurement range for my PM

CEMS? Initially, your PM CEMS must be set up to measure over

the expected range of your source’s PM emission concentrations

during routine operations. You may change the measurement

range to a more appropriate range prior to correlation

testing. 

6.4 What if my PM CEMS does automatic range switching? 

Your PM CEMS may be equipped to perform automatic range

switching so that it is operating in a range most sensitive to

the detected concentrations. If your PM CEMS does automatic

range switching, you must configure the data recorder to

handle the recording of data values in multiple ranges during

range-switching intervals.

6.5 What averaging time and sample intervals should be
used? Your CEMS must sample the stack effluent such that the

averaging time, the number of measurements in an average, the

minimum sampling time, and the averaging procedure for

reporting and determining compliance conform with those

specified in the applicable regulation. Your PM CEMS must be

designed to meet the specified response time and cycle time

established in this performance specification (see section

13.3).

6.6 What type of equipment is needed for my data

recorder? Your CEMS data recorder must be able to accept and

record electronic signals from all the monitors associated

with your PM CEMS. 

(1) Your data recorder must record the signals from your

PM CEMS that can be correlated to PM mass concentrations. If

your PM CEMS uses multiple ranges, your data recorder must

identify what range the measurement was made in and provide

range-adjusted results. 

(2) Your data recorder must accept and record monitor

status signals (flagged data). 

(3) Your data recorder must accept signals from

auxiliary data monitors, as appropriate.

6.7 What other equipment and supplies might I need? You

may need other supporting equipment as defined by the

applicable reference method(s) (see section 7) or as specified

by your CEMS manufacturer.

7.0 What reagents and standards do I need?

You will need reference standards or procedures to

perform the zero drift check, the upscale drift check, and the

sample volume check.

7.1 What is the reference standard value for the zero

drift check? You must use a zero check value that is no

greater than 20 percent of the PM CEMS’s response range. You

must obtain documentation on the zero check value from your PM

CEMS manufacturer.

7.2 What is the reference standard value for the upscale

drift check? You must use an upscale check value that

produces a response between 50 and 100 percent of the PM

CEMS’s response range. For a PM CEMS that produces output

over a range of 4 mA to 20 mA, the upscale check value must

produce a response in the range of 12 mA to 20 mA. You must

obtain documentation on the upscale check value from your PM

CEMS manufacturer.

7.3 What is the reference standard value for the sample

volume check? You must use a reference standard value or

procedure that produces a sample volume value equivalent to

the normal sampling rate. You must obtain documentation on

the sample volume value from your PM CEMS manufacturer.

8.0 What performance specification test procedure do I
follow?

You must complete each of the activities in sections 8.1

through 8.8 for your performance specification test. 

8.1 How should I select and set up my equipment? You

should select a PM CEMS that is appropriate for your source,

giving consideration to potential factors such as flue gas

conditions, interferences, site-specific configuration,

installation location, PM concentration range, and other PM

characteristics. Your PM CEMS must meet the equipment

specifications in sections 6.1 and 6.2.

(1) You should select a PM CEMS that is appropriate for

the flue gas conditions at your source. If your source’s flue

gas contains entrained water droplets, we recommend that your

PM CEMS include a sample delivery and conditioning system that

is capable of extracting and heating a representative sample. 

(i) Your PM CEMS must maintain the sample at a

temperature sufficient to prevent moisture condensation in the

sample line before analysis of PM.

(ii) If condensible PM is an issue, we recommend that

you operate your PM CEMS to maintain the sample gas

temperature at the same temperature as the reference method

filter.

(iii) Your PM CEMS must avoid condensation in the sample

flow rate measurement lines.

(2) Some PM CEMS do not have a wide measurement range

capability. Therefore, you must select a PM CEMS that is

capable of measuring the full range of PM concentrations

expected from your source from normal levels through the

emission limit concentration.

(3) Some PM CEMS are sensitive to particle size changes,

water droplets in the gas stream, particle charge, stack gas

velocity changes, or other factors. Therefore, you should

select a PM CEMS appropriate for the emission characteristics

of your source.

(4) We recommend that you consult your PM CEMS vendor to

obtain basic recommendations on the instrument capabilities

and setup configuration. You are ultimately responsible for

setup and operation of your PM CEMS.

8.2 Where do I install my PM CEMS? You must install

your PM CEMS at an accessible location downstream of all

pollution control equipment. You must perform your PM CEMS

concentration measurements from a location considered 

representative or be able to provide data that can be

corrected to be representative of the total PM emissions as

determined by the manual reference method. 

(1) You must select a measurement location that minimizes

problems due to flow disturbances, cyclonic flow, and varying

PM stratification (refer to Method 1 for guidance). 
(2) If you plan to achieve higher emissions for

correlation test purposes by adjusting the performance of the

air pollution control device (per section 8.6(4)(i)), you must

locate your PM CEMS and reference method sampling points well

downstream of the control device (e.g., downstream of the

induced draft fan), in order to minimize PM stratification

that may be created in these cases.

8.3 How do I select the reference method measurement

location and traverse points? You must follow EPA Method 1

for identifying manual reference method traverse points. 

Ideally, you should perform your manual reference method

measurements at locations that satisfy the measurement site

selection criteria specified in EPA Method 1 of at least eight

duct diameters downstream and at least two duct diameters

upstream of any flow disturbance. Where necessary, you may

conduct testing at a location that is two diameters downstream

and 0.5 diameters upstream of flow disturbances. If your

location does not meet the minimum downstream and upstream

requirements, you must obtain approval from us to test at your

location.

8.4 What are my pretest preparation steps? You must

install your CEMS and prepare the reference method test site

according to the specifications in sections 8.2 and 8.3.

(1) After completing the initial field installation, we

recommend that you operate your PM CEMS according to the

manufacturer's instructions to familiarize yourself with its

operation before you begin correlation testing.

(i) During this initial period of operation, we recommend

that you conduct daily checks (zero and upscale drift and

sample volume, as appropriate), and, when any check exceeds

the daily specification (see section 13.1), make adjustments

and perform any necessary maintenance to ensure reliable

operation.

(2) When you are confident that your PM CEMS is operating

properly, we recommend that you operate your CEMS over a

correlation test planning period of sufficient duration to

identify the full range of operating conditions and PM

emissions to be used in your PM CEMS correlation test.

(i) During the correlation test planning period, you

should operate the process and air pollution control equipment

over the normal range of operating conditions, except when you

attempt to produce higher emissions.

(ii) Your data recorder should record PM CEMS response

during the full range of routine process operating conditions.

(iii) You should try to establish the relationships

between operating conditions and PM CEMS response, especially

those conditions that produce the highest PM CEMS response

over 15-minute averaging periods, and the lowest PM CEMS
response as well. The objective is to be able to reproduce

the conditions for purposes of the actual correlation testing

discussed in section 8.6.

(3) You must set the response range of your PM CEMS such

that the instrument measures the full range of responses that

correspond to the range of source operating conditions that

you will implement during correlation testing.

(4) We recommend that you perform preliminary reference

method testing after the correlation test planning period. 

During this preliminary testing, you should measure the PM

emission concentration corresponding to the highest PM CEMS

response observed during the full range of normal operation,

when perturbing the control equipment, or as the result of PM

spiking.

(5) Before performing correlation testing, you must

perform a 7-day zero and upscale drift test (see section 8.5).

(6) You must not change the response range of the

monitor once the response range has been set and the drift

test successfully completed.

8.5 How do I perform the 7-day drift test? You must

check the zero (or low-level value between 0 and 20 percent of

the response range of the instrument) and upscale (between 50

and 100 percent of the instrument’s response range) drift. 

You must perform this check at least once daily over 7

consecutive days. Your PM CEMS must quantify and record the

zero and upscale measurements and the time of the

measurements. If you make automatic or manual adjustments to

your PM CEMS zero and upscale settings, you must conduct the

drift test immediately before these adjustments, or conduct it

in such a way that you can determine the amount of drift. You

will find the calculation procedures for drift in section 12.1

and the acceptance criteria for allowable drift in section

13.1.

(1) What is the purpose of 7-day drift tests? The

purpose of the 7-day drift test is to demonstrate that your

system is capable of operating in a stable manner and

maintaining its calibration for at least a 7-day period.

(2) How do I conduct the 7-day drift test? To conduct

the 7-day drift test, you must determine the magnitude of the

drift once each day, at 24-hour intervals, for 7 consecutive

days while your source is operating normally.

(i) You must conduct the 7-day drift test at the two

points specified in section 8.5. You may perform the 7-day

drift tests automatically or manually by introducing to your

PM CEMS suitable reference standards (these need not be

certified) or by using other appropriate procedures. 

(ii) You must record your PM CEMS zero and upscale

response and evaluate them against the zero check value and
upscale check value. 

(3) When must I conduct the 7-day drift test? You must

complete a valid 7-day drift test before attempting the

correlation test.

8.6 How do I conduct my PM CEMS correlation test? You

must conduct the correlation test according to the procedure

given in paragraphs (1) through (5) of this section. If you

need multiple correlations, you must conduct sufficient

testing and collect at least 15 pairs of reference method and

PM CEMS data for calculating each separate correlation.

(1) You must use the reference method for PM (usually

EPA Methods 5, 5I, or 17) that is prescribed by the applicable

regulations. You may need to perform other reference methods

or performance specifications (e.g., Method 3 for oxygen,

Method 4 for moisture, etc.) depending on the units in which

your PM CEMS reports PM concentration.

(i) We recommend that you use paired reference method

trains when collecting manual PM data to identify and screen

the reference method data for imprecision and bias. 

Procedures for checking reference method data for bias and

precision can be found in the PM CEMS Knowledge Document (see

section 16.5).

(ii) You may use test runs that are shorter than 60

minutes in duration (e.g., 20 or 30 minutes). You may perform

your PM CEMS correlation tests during new source performance

standards performance tests or other compliance tests subject

to the Clean Air Act or other statutes, such as the Resource

Conservation and Recovery Act. In these cases, your reference

method results obtained during the PM CEMS correlation test

may be used to determine compliance so long as your source and

the test conditions and procedures (e.g., reference method

sample run durations) are consistent with the applicable

regulations and the reference method.

(iii) You must convert the reference method results to

units consistent with the conditions of your PM CEMS

measurements. For example, if your PM CEMS measures and

reports PM emissions in the units of mass per actual volume of

stack gas, you must convert your reference method results to

those units (e.g., mg/acm). If your PM CEMS extracts and

heats the sample gas to eliminate water droplets, then

measures and reports PM emissions under those actual

conditions, you must convert your reference method results to

those same conditions (e.g., mg/acm at 160°C).

(2) During each test run, you must coordinate process

operations, reference method sampling, and PM CEMS operations. 

For example, you must ensure that the process is operating at

the targeted conditions, both reference method trains are

sampling simultaneously (if paired sampling trains are being
used), and your PM CEMS and data logger are operating

properly. 

(i) You must coordinate the start and stop times of each

run between the reference method sampling and PM CEMS

operation. For a batch sampling PM CEMS, you must start the

reference method at the same time as your PM CEMS sampling. 

(ii) You must note the times for port changes (and other

periods when the reference method sampling may be suspended)

on the data sheets so that you can adjust your PM CEMS data

accordingly, if necessary. 

(iii) You must properly align the time periods for your

PM CEMS and your reference method measurements to account for

your PM CEMS response time.

(3) You must conduct a minimum of 15 valid runs each

consisting of simultaneous PM CEMS and reference method

measurement sets. 

(i) You may conduct more than 15 sets of CEMS and

reference method measurements. If you choose this option, you

may reject certain test results so long as the total number of

valid test results you use to determine the correlation is

greater than or equal to 15. 

(ii) You must report all data, including the rejected

data.

(iii) You may reject the results of up to five test runs

without explanation.

(iv) If you reject the results of more than five test

runs, the basis for rejecting the results of the additional

test runs must be explicitly stated in the reference method,

this performance specification, Procedure 2 of appendix F, or

your quality assurance plan.

(4) Simultaneous PM CEMS and reference method

measurements must be performed in a manner to ensure that the

range of data that will be used to establish the correlation

for your PM CEMS is maximized. You must first attempt to

maximize your correlation range by following the procedures

described in paragraphs (4)(i) through (iv) of this section. 

If you cannot obtain the three levels as described in

paragraphs (i) through (iv), then you must use the procedure

described in section 8.6(5).

(i) You must attempt to obtain the three different

levels of PM mass concentration by varying process operating

conditions, varying PM control device conditions, or by means

of PM spiking.

(ii) The three PM concentration levels you use in the

correlation tests must be distributed over the complete

operating range experienced by your source.

(iii) At least 20 percent of the minimum 15 measured

data points you use should be contained in each of the
following levels:

• Level 1: From no PM (zero concentration) emissions

to 50 percent of the maximum PM concentration;

• Level 2: 25 to 75 percent of the maximum PM

concentration; and

• Level 3: 50 to 100 percent of the maximum PM

concentration.

(iv) Although the above levels overlap, you may only

apply individual run data to one level. 

(5) If you cannot obtain three distinct levels of PM

concentration as described, you must perform correlation

testing over the maximum range of PM concentrations that is

practical for your PM CEMS. To ensure that the range of data

used to establish the correlation for your PM CEMS is

maximized, you must follow one or more of the steps in

paragraphs (5)(i) through (iv) of this section.

(i) Zero point data for in-situ instruments should be

obtained, to the extent possible, by removing the instrument

from the stack and monitoring ambient air on a test bench. 

(ii) Zero point data for extractive instruments should

be obtained by removing the extractive probe from the stack

and drawing in clean ambient air.

(iii) Zero point data also can be obtained by performing

manual reference method measurements when the flue gas is free

of PM emissions or contains very low PM concentrations (e.g.,

when your process is not operating, but the fans are operating

or your source is combusting only natural gas).

(iv) If none of the steps in paragraphs (5)(i) through

(iii) of this section are possible, you must estimate the

monitor response when no PM is in the flue gas (e.g., 4 mA = 0

mg/acm).

8.7 What do I do with the initial correlation test data

for my PM CEMS? You must calculate and report the results of

the correlation testing, including the correlation

coefficient, confidence interval, and tolerance interval for

the PM CEMS response and reference method correlation data

that are use to establish the correlation, as specified in

section 12. You must include all data sheets, calculations,

charts (records of PM CEMS responses), process data records

including PM control equipment operating parameters, and

reference media certifications necessary to confirm that your

PM CEMS met the requirements of this performance

specification. In addition, you must:

(1) Determine the integrated (arithmetic average) PM CEMS

output over each reference method test period;

(2) Adjust your PM CEMS outputs and reference method test

data to the same clock time (considering response time of your

PM CEMS);
(3) Confirm that the reference method results are

consistent with your PM CEMS response in terms of, where

applicable, moisture, temperature, pressure, and diluent

concentrations; and

(4) Determine whether any of the reference method test

results do not meet the test method criteria.

8.8 What is the limitation on the range of my PM CEMS

correlation? Although the data you collect during the

correlation testing should be representative of the full range

of normal operating conditions at your source, you must

conduct additional correlation testing if either of the

conditions specified in paragraphs (1) and (2) of this section

occurs. 

(1) If your source is a low-emitting source, as defined

in section 3.16 of this specification, you must conduct

additional correlation testing if either of the events

specified in paragraphs (1)(i) or (ii) of this section occurs

while your source is operating under normal conditions.

(i) Your source generates 24 consecutive hourly average

PM CEMS responses that are greater than 125 percent of the

highest PM CEMS response (e.g., mA reading) used for the

correlation curve or are greater than the PM CEMS response

that corresponds to 50 percent of the emission limit,

whichever is greater, or 

(ii) The cumulative hourly average PM CEMS responses

generated by your source are greater than 125 percent of the

highest PM CEMS response used for the correlation curve or are

greater than the PM CEMS response that corresponds to 50

percent of the emission limit, whichever is greater, for more

than 5 percent of your PM CEMS operating hours for the

previous 30-day period.

(2) If your source is not a low-emitting source, as

defined in section 3.16 of this specification, you must

conduct additional correlation testing if either of the events

specified in paragraph (i) or (ii) of this section occurs

while your source is operating under normal conditions.

(i) Your source generates 24 consecutive hourly average

PM CEMS responses that are greater than 125 percent of the

highest PM CEMS response (e.g., mA reading) used for the

correlation curve, or 

(ii) The cumulative hourly average PM CEMS responses

generated by your source are greater than 125 percent of the

highest PM CEMS response used for the correlation curve for

more than 5 percent of your PM CEMS operating hours for the

previous 30-day period.

(3) If additional correlation testing is required, you

must conduct at least three additional test runs under the

conditions that caused the higher PM CEMS response.
(i) You must complete the additional testing and use the

resulting new data along with the previous data to calculate a

revised correlation equation within 60 days after the

occurrence of the event that requires additional testing, as

specified in paragraphs 8.8(1) and (2).

(4) If your source generates consecutive PM CEMS hourly

responses that are greater than 125 percent of the highest PM

CEMS response used to develop the correlation curve for 24

hours or for a cumulative period that amounts to more than 5

percent of the PM CEMS operating hours for the previous 30-day

period, you must report the reason for the higher PM CEMS

responses.

9.0 What quality control measures are required?

Quality control measures for PM CEMS are specified in 40

CFR 60, Appendix F, Procedure 2.

10.0 What calibration and standardization procedures must I

perform? [Reserved]

11.0 What analytical procedures apply to this procedure? 

Specific analytical procedures are outlined in the

applicable reference method(s).

12.0 What calculations and data analyses are needed?

You must determine the primary relationship for

correlating the output from your PM CEMS to a PM

concentration, typically in units of mg/acm or mg/dscm of flue

gas, using the calculations and data analysis process in

sections 12.2 and 12.3. You develop the correlation by

performing an appropriate regression analysis between your PM

CEMS response and your reference method data. 

12.1 How do I calculate upscale drift and zero drift? 

You must determine the difference in your PM CEMS output

readings from the established reference values (zero and

upscale check values) after a stated period of operation

during which you performed no unscheduled maintenance, repair,

or adjustment.

(1) Calculate the upscale drift (UD) using Equation 11-

1:

UD (Eq. 11-1)

R R

R

100 CEM U

U

=

−

×

where:

UD = The upscale (high-level) drift of your PM CEMS

in percent,

RCEM = The measured PM CEMS response to the upscale

reference standard, and 

RU = The preestablished numerical value of the

upscale reference standard. 

(2) Calculate the zero drift (ZD) using Equation 11-2:
ZD (Eq. 11-2)

R R

R

100 CEM L

U

=

−

×

where:

ZD = The zero (low-level) drift of your PM CEMS in

percent,

RCEM = The measured PM CEMS response to the zero

reference standard,

RL = The preestablished numerical value of the zero

reference standard, and

RU = The preestablished numerical value of the

upscale reference standard. 

(3) Summarize the results on a data sheet similar to

that shown in Table 2 (see section 17).

12.2 How do I perform the regression analysis? You must

couple each reference method PM concentration measurement, y,

in the appropriate units, with an average PM CEMS response, x,

over corresponding time periods. You must complete your PM

CEMS correlation calculations using data deemed acceptable by

quality control procedures identified in 40 CFR 60, Appendix

F, Procedure 2.

(1) You must evaluate all flagged or suspect data

produced during measurement periods and determine whether they

should be excluded from your PM CEMS’s average.

(2) You must assure that the reference method and PM

CEMS results are on a consistent moisture, temperature, and

diluent basis. You must convert the reference method PM

concentration measurements (dry standard conditions) to the

units of your PM CEMS measurement conditions. The conditions

of your PM CEMS measurement are monitor-specific. You must

obtain from your PM CEMS vendor or instrument manufacturer the

conditions and units of measurement for your PM CEMS.

(i) If your sample gas contains entrained water droplets

and your PM CEMS is an extractive system that measures at

actual conditions (i.e., wet basis), you must use the measured

moisture content determined from the impinger analysis when

converting your reference method PM data to PM CEMS

conditions; do not use the moisture content calculated from a

psychrometric chart based on saturated conditions.

12.3 How do I determine my PM CEMS correlation? To

predict PM concentrations from PM CEMS responses, you must use

the calculation method of least squares presented in

paragraphs (1) through (5) of this section. When performing

the calculations, each reference method PM concentration

measurement must be treated as a discrete data point; if using

paired sampling trains, do not average reference method data

pairs for any test run.
This performance specification describes procedures for

evaluating five types of correlation models: linear,

polynomial, logarithmic, exponential, and power. Procedures

for selecting the most appropriate correlation model are

presented in section 12.4 of this specification.

(1) How do I evaluate a linear correlation for my

correlation test data? To evaluate a linear correlation,

follow the procedures described in paragraphs (1)(i) through

(iv) of this section.

(i) Calculate the linear correlation equation, which

gives the predicted PM concentration (í) as a function of the

PM CEMS response (x), as indicated by Equation 11-3:

y$ = b0 + b1x (Eq. 11-3)

where:

í = the predicted PM concentration,

b0 = the intercept for the correlation curve, as

calculated using Equation 11-4,

b1 = the slope of the correlation curve, as

calculated using Equation 11-6, and

x = the PM CEMS response value.

Calculate the y intercept (b0) of the correlation curve using

Equation 11-4:

b0 = y − b1⋅ x (Eq. 11-4)

where:

xG = the mean value of the PM CEMS response data, as

calculated using Equation 11-5, and

yG = the mean value of the PM concentration data, as

calculated using Equation 11-5:

x (Eq. 11-5) 1

n

x , y

1

n

y i

i 1

n

i

i 1

n

= =

= =

∑ ∑

where:

xi = the PM CEMS response value for run i,

yi = the PM concentration value for run i, and

n = the number of data points.

Calculate the slope (b1) of the correlation curve using

Equation 11-6:

b (Eq. 11-6)

S

S

1

xy

xx

=

where:

Sxx, Sxy = as calculated using Equation 11-7:

(Eq. 11-7) S (x x) , S (x x)(y y) xx i

2

i 1

n

xy i i

i 1

n

= − = − −

= =

∑ ∑

(ii) Calculate the half range of the 95 percent

confidence interval (CI) for the predicted PM concentration
(yG) at the mean value of x, using Equation 11-8:

CI t S (Eq. 11-8)

1

n

df,1 a/2 L = ⋅ −

where:

CI = the half range for the 95 percent confidence

interval for the mean x value,

 tdf,1-a/2 = the value for the t statistic provided in

Table 1 for df = n-2, and

SL = the scatter or deviation of í values about the

correlation curve, which is determined using

Equation 11-9:

S ( ) (Eq. 11-9) 1

n 2

L yi yi

2

i 1

n

=

−

−

=

∑ $

Calculate the confidence interval half range at the mean x

value as a percentage of the emission limit (CI%) using

Equation 11-10:

CI% (Eq. 11-10)

CI

EL

= ⋅100%

where:

CI = the confidence interval half range at the mean x

value, and

EL = PM emission limit, as described in section 13.2.

(iii) Calculate the half range of the tolerance interval

at the mean x value (TI) using Equation 11-11:

TI k S (Eq. 11-11) t L = ⋅

where:

TI = the tolerance interval half range at the mean x

value, 

kt = as calculated using Equation 11-12, and

SL = as calculated using Equation 11-9:

k u v (Eq. 11-12) t n df= ⋅

′

where:

n’ = the number of test runs (n),

un’ = the tolerance factor for 75 percent provided in

Table 1, and

vdf = the value from Table 1 for df = n - 2.

Calculate the tolerance interval half range at the mean x

value as a percentage of the emission limit (TI%) using

Equation 11-13:

TI% (Eq. 11-13)

TI

EL

= ⋅100%

where:

TI = the tolerance interval half range at the mean

value of x, and 
EL = PM emission limit, as described in section 13.2.

(iv) Calculate the linear correlation coefficient (r)

using Equation 11-14:

r 1 (Eq. 11-14) S

S

L

2

y

2 = −

where:

SL = as calculated using Equation 11-9, and

Sy = as calculated using Equation 11-15:

(Eq. 11-15)

( )

S

y y

n 1

y

i

2

i 1

n

=

−

−

=

∑

(2) How do I evaluate a polynomial correlation for my

correlation test data? To evaluate a polynomial correlation,

follow the procedures described in paragraphs (2)(i) through

(iv) of this section.

(i) Calculate the polynomial correlation equation, which

is indicated by Equation 11-16, using Equations 11-17 through

11-22:

y$ b0 b1x b2x (Eq. 11-16) 2= + +

where:

í = the PM CEMS concentration predicted by the

polynomial correlation equation, and

b0, b1, b2 = the coefficients determined from the

solution to the matrix equation Ab=B where:

A 

n S S

S S S

S S S

, b 

b

b

b

, B 

S

S

S

.

1 2

1 2 3

2 3 4

0

1

2

5

6

7

=





















=





















=





















S1 (xi ),S2 (x ),S (x ), S (x ), (Eq. 11-17)

i 1

n

i

2

i 1

n

3 i

3

4 i

4

i 1

n

i 1

n

= = = =

= = = =

∑ ∑ ∑ ∑

S (y ), S (x y ), S (x y ). (Eq. 11-18)

5 i

i 1

n

6 i i

i 1

n

7 i

2

i

i 1

n

= = =

= = =

∑ ∑ ∑

where:

xi = the PM CEMS response for run i,

yi = the reference method PM concentration for run i,

and

n = the number of test runs.

Calculate the polynomial correlation curve coefficients (b0,

b1, and b2) using Equations 11-19 to 11-21, respectively:

( )

b

S S S S S S S S S S S S S S S S S S

detA 0

5 2 4 1 3 7 2 6 3 7 2 2 3 3 5 4 6 1

=

⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅

(Eq. 11-19)
( )

b

n S S S S S S S S S S S S S n S S S

detA 1

6 4 5 3 2 2 1 7 2 6 2 7 3 4 1 5

=

⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅

(Eq. 11-20)

( )

b

n S S S S S S S S S S S S S n S S S

detA 2

2 7 1 6 2 5 1 3 2 2 5 3 6 7 1 1

=

⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅

(Eq. 11-21)

where:

det A n S2 S4 S2 S2 S1 S3 S2 S3 S3 n S2 S1 S3 S4 S1 S1 = ⋅ ⋅ − ⋅ + ⋅ ⋅ − ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅

(Eq. 11-22)

(ii) Calculate the confidence interval half range (CI)

by first calculating the C coefficients (C0 to C5) using

Equations 11-23 and 11-24:

( ) ( ) ( )

( ) ( ) ( )

C

S S S

D

, C

S S S S

D

, C

S S S

D

,

C

nS S

D

, C

S S nS

D

, C

nS S

D

0

2 4 3

2

1

3 2 1 4

2

1 3 2

2

3

4 2

2

4

1 2 3

5

2 1

2

=

⋅ −

=

⋅ − ⋅

=

⋅ −

=

−

=

⋅ −

=

−

(Eq. 11-23)

where:

D n(S S S ) S (S S S S ) S (S S S ) 2 4 3

2

1 3 2 1 4 2 1 3 2

2

= ⋅ − + ⋅ − ⋅ + ⋅ − (Eq. 11-24)

Calculate ) using Equation 11-25 for each x value:

Δ = C + 2C x + (2C + C )x + 2C x + C x (Eq. 11-25) 0 1 2 3

2

4

3

5

4

Determine the x value that corresponds to the minimum value of

) ()min). Determine the scatter or deviation of í values about

the polynomial correlation curve (SP) using Equation 11-26:

S ( ) (Eq. 11-26) 1

n 3

P yi yi

2

i 1

n

=

−

−

=

∑ $

Calculate the half range of the 95 percent confidence interval

(CI) at the x value that corresponds to )min using Equation 11-

27:

(Eq. 11-27) CI= tdf SP Dmin ⋅

where:

df = n-3, and

tdf = as listed in Table 1 (see section 17).

Calculate the confidence interval half range at the x

value for )min as a percentage of the emission limit (CI%)

using Equation 11-28:

CI (Eq. 11-28) CI

EL

% = ⋅ 100%

where:

CI = the confidence interval half range at the x
value that corresponds to )min, and

EL = PM emission limit, as described in section

13.2.

(iii) Calculate the tolerance interval half range

(TI) at the x value for )min, as indicated in Equation 11-

29 for the polynomial correlation, using Equations 11-30

and 11-31:

TI k S (Eq. 11-29) T P = ⋅

where:

k u v (Eq. 11-30) T = n df ⋅

′

n′ = (Eq. 11-31)

1

Δ min

un’ = the value indicated in Table 1, and

vdf = the value indicated in Table 1 for df = n3. 

If the calculated value for n’ is less than 2, then n’ =

2.

Calculate the tolerance interval half range at the x value

for )min as a percentage of the emission limit (TI%) using

Equation 11-32:

TI (Eq. 11-32)

TI

EL

% = ⋅ 100%

where:

TI = the tolerance interval half range at the x

value that corresponds to )min, and 

EL = PM emission limit, as described in section

13.2.

(iv) Calculate the polynomial correlation

coefficient (r) using Equation 11-33:

r 1 (Eq. 11-33)

S

S

P

2

y

2 = −

where:

SP = as calculated using Equation 11-26, and

Sy = as calculated using Equation 11-15.

(3) How do I evaluate a logarithmic correlation for

my correlation test data? To evaluate a logarithmic

correlation, which has the form indicated by Equation 11-

34, follow the procedures described in paragraphs (3)(i)

through (iii) of this section.

y$ = b0 + b1Ln(x) (Eq. 11-34)

(i) Perform a logarithmic transformation of each PM

CEMS response value (x values) using Equation 11-35:

 xi’ = Ln(xi) (Eq. 11-35)

where:
xi’ = is the transformed value of xi, and

Ln(xi) = the natural logarithm of the PM CEMS

response for run i.

(ii) Using the values for xi’ in place of the values

for xi, perform the same procedures used to develop the

linear correlation equation described in paragraph (1)(i)

of this section. The resulting equation has the form

indicated by Equation 11-36:

y$ = b0 + b1x′ (Eq. 11-36)

where:

x’ = the natural logarithm of the PM CEMS

response, and the variables í, b0, and b1

are as defined in paragraph (1)(i) of this

section.

(iii) Using the values for xi’ in place of the

values for xi, calculate the confidence interval half

range at the mean x’ value as a percentage of the emission

limit (CI%), the tolerance interval half range at the mean

x’ value as a percentage of the emission limit (TI%), and

the correlation coefficient (r) using the procedures

described in paragraphs (1)(ii) through (iv) of this

section.

(4) How do I evaluate an exponential correlation for

my correlation test data? To evaluate an exponential

correlation, which has the form indicated by Equation 11-

37, follow the procedures described in paragraphs (4)(i)

through (v) of this section:

y$ b e (Eq. 11-37) 1

b x

= 0

(i) Perform a logarithmic transformation of each PM

concentration measurement (y values) using Equation 11-38:

y Ln(y ) (Eq. 11-38) i i

′ =

where:

yi’ = is the transformed value of yi, and

 Ln(yi) = the natural logarithm of the PM

concentration measurement for run i.

(ii) Using the values for yi’ in place of the values

for yi, perform the same procedures used to develop the

linear correlation equation described in paragraph (1)(i)

of this section. The resulting equation will have the

form indicated by Equation 11-39.

y$ ′ = b0 + b1x (Eq. 11-39)

where:

í’ = the natural logarithm of the predicted PM

concentration values, and the variables b0,

b1, and x are as defined in paragraph (1)(i)
of this section.

(iii) Using the values for yi’ in place of the

values for yi, calculate the confidence interval half

range (CI), as described in paragraph (1)(ii) of this

section. However, for the exponential correlation, you

must calculate the value for CI at the median x value,

instead of the mean x value for linear correlations. 

Calculate the confidence interval half range at the median

x value as a percentage of the emission limit (CI%) using

Equation 11-40:

CI% (Eq. 11-40)

CI

Ln(EL)

= ⋅100%

where:

CI = the confidence interval half range at the

median x value, and

Ln(EL) = the natural logarithm of the PM emission

limit, as described in section 13.2.

(iv) Using the values for yi’ in place of the values

for yi, calculate the tolerance interval half range (TI),

as described in paragraph (1)(iii) of this section. For

the exponential correlation, the value for TI also must be

calculated at the median x value. Calculate the tolerance

interval half range at the median x value as a percentage

of the emission limit (TI%) using Equation 11-41:

TI% (Eq. 11-41)

TI

Ln(EL)

= ⋅100%

where:

TI = the tolerance interval half range at the

median x value, and

Ln(EL) = the natural logarithm of the PM emission

limit, as described in section 13.2.

(v) Using the values for yi’ in place of the values

for yi, calculate the correlation coefficient (r) using

the procedure described in paragraph (1)(iv) of this

section.

(5) How do I evaluate a power correlation for my

correlation test data? To evaluate a power correlation,

which has the form indicated by Equation 11-42, follow the

procedures described in paragraphs (5)(i) through (v) of

this section.

y$ b x (Eq. 11-42) 1

b0 =

(i) Perform logarithmic transformations of each PM

CEMS response (x values) and each PM concentration

measurement (y values) using Equations 11-35 and 11-38,

respectively.
(ii) Using the values for xi’ in place of the values

for xi, and the values for yi’ in place of the values for

yi, perform the same procedures used to develop the linear

correlation equation described in paragraph (1)(i) of this

section. The resulting equation will have the form

indicated by Equation 11-43:

y$ ′ = b0 + b1x′ (Eq. 11-43)

where:

í’ = the natural logarithm of the predicted PM

concentration values, and

x’ = the natural logarithm of the PM CEMS

response values, and the variables b0 and b1

are as defined in paragraph (1)(i) of this

section.

(iii) Using the values for yi’ in place of the

values for yi, calculate the confidence interval half

range (CI), as described in paragraph (1)(ii) of this

section. You must calculate the value for CI at the

median x’ value, instead of the mean x value for linear

correlations. Calculate the confidence interval half

range at the median x’ value as a percentage of the

emission limit (CI%) using Equation 11-40.

(iv) Using the values for yi’ in place of the values

for yi, calculate the tolerance interval half range (TI),

as described in paragraph (1)(iii) of this section. The

value for TI also must be calculated at the median x’

value. Calculate the tolerance interval half range at the

median x’ value as a percentage of the emission limit

(CI%) using Equation 11-41.

(v) Using the values for yi’ in place of the values

for yi, calculate the correlation coefficient (r) using

the procedure described in paragraph (1)(iv) of this

section.

12.4 Which correlation model should I use? Follow

the procedures described in paragraphs (1) through (4) of

this section to determine which correlation model you

should use.

(1) For each correlation model that you develop

using the procedures described in section 12.3 of this

specification, compare the confidence interval half range

percentage, tolerance interval half range percentage, and

correlation coefficient to the performance criteria

specified in section 13.2 of this specification. You can

use the linear, logarithmic, exponential, or power

correlation model if the model satisfies all of the

performance criteria specified in section 13.2 of this
specification. However, to use the polynomial model you

first must check that the polynomial correlation curve

satisfies the criteria for minimum and maximum values

specified in paragraph (3) of this section.

(2) If you develop more than one correlation curve

that satisfy the performance criteria specified in section

13.2 of this specification, you should use the correlation

curve with the greatest correlation coefficient. If the

polynomial model has the greatest correlation coefficient,

you first must check that the polynomial correlation curve

satisfies the criteria for minimum and maximum values

specified in paragraph (3) of this section.

(3) You can use the polynomial model that you

develop using the procedures described in section 12.3(2)

if the model satisfies the performance criteria specified

in section 13.2 of this specification, and the minimum or

maximum value of the polynomial correlation curve does not

occur within the expanded data range. The minimum or

maximum value of the polynomial correlation curve is the

point where the slope of the curve equals zero. To

determine if the minimum or maximum value occurs within

the expanded data range, follow the procedure described in

paragraphs (3)(i) through (iv) of this section.

(i) Determine if your polynomial correlation curve

has a minimum or maximum point by comparing the polynomial

coefficient b2 to zero. If b2 is less than zero, the curve

has a maximum value. If b2 is greater than zero, the

curve has a minimum value. (Note: If b2 equals zero, the

correlation curve is linear.)

(ii) Calculate the minimum value using Equation 11-

44.

maximum or minimum = − (Eq. 11-44)

b

2b

1

2

(iii) If your polynomial correlation curve has a

minimum point, you must compare the minimum value to the

minimum PM CEMS response used to develop the correlation

curve. If the correlation curve minimum value is less

than or equal to the minimum PM CEMS response value, you

can use the polynomial correlation curve, provided the

correlation curve also satisfies all of the performance

criteria specified in section 13.2 of this specification. 

If the correlation curve minimum value is greater than the

minimum PM CEMS response value, you cannot use the

polynomial correlation curve to predict PM concentrations.

(iv) If your polynomial correlation curve has a

maximum, the maximum value must be greater than the

allowable extrapolation limit. If your source is not a
low-emitting source, as defined in section 3.16 of this

specification, the allowable extrapolation limit is 125

percent of the highest PM CEMS response used to develop

the correlation curve. If your source is a low-emitting

source, the allowable extrapolation limit is 125 percent

of the highest PM CEMS response used to develop the

correlation curve or the PM CEMS response that corresponds

to 50 percent of the emission limit, whichever is greater. 

If the polynomial correlation curve maximum value is

greater than the extrapolation limit, and the correlation

curve satisfies all of the performance criteria specified

in section 13.2 of this specification, you can use the

polynomial correlation curve to predict PM concentrations. 

If the correlation curve maximum value is less than the

extrapolation limit, you cannot use the polynomial

correlation curve to predict PM concentrations.

(4) You may petition the Administrator for

alternative solutions or sampling recommendations if the

correlation models described in section 12.3 of this

specification do not satisfy the performance criteria

specified in section 13.2 of this specification.

13.0 What are the performance criteria for my PM CEMS?

You must evaluate your PM CEMS based on the 7-day drift

check, the accuracy of the correlation, and the sampling

periods and cycle/response time.

13.1 What is the 7-day drift check performance

specification? Your daily PM CEMS internal drift checks

must demonstrate that the average daily drift of your PM

CEMS does not deviate from the value of the reference

light, optical filter, Beta attenuation signal, or other

technology-suitable reference standard by more than 2

percent of the upscale value. If your CEMS includes

diluent and/or auxiliary monitors (for temperature,

pressure, and/or moisture) that are employed as a

necessary part of this performance specification, you must

determine the calibration drift separately for each

ancillary monitor in terms of its respective output (see

the appropriate performance specification for the diluent

CEMS specification). None of the calibration drifts may

exceed their individual specification.

13.2 What performance criteria must my PM CEMS

correlation satisfy? Your PM CEMS correlation must meet

each of the minimum specifications in paragraphs (1), (2),

and (3) of this section. Before confidence and tolerance

interval half range percentage calculations are made, you

must convert the emission limit to the appropriate units

of your PM CEMS measurement conditions using the average

of emissions gas property values (e.g., diluent
concentration, temperature, pressure, and moisture)

measured during the correlation test.

(1) The correlation coefficient must satisfy the

criterion specified in paragraph (1)(i) or (ii), whichever

applies.

(i) If your source is not a low-emitting source, as

defined in section 3.16 of this specification, the

correlation coefficient (r) must be greater than or equal

to 0.85.

(ii) If your source is a low-emitting source, as

defined in section 3.16 of this specification, the

correlation coefficient (r) must be greater than or equal

to 0.75.

(2) The confidence interval half range must satisfy

the applicable criterion specified in paragraph (2)(i),

(ii), or (iii) of this section, based on the type of

correlation model.

(i) For linear or logarithmic correlations, the 95

percent confidence interval half range at the mean PM CEMS

response value from the correlation test must be within 10

percent of the PM emission limit value specified in the

applicable regulation, as calculated using Equation 11-10.

(ii) For polynomial correlations, the 95 percent

confidence interval half range at the PM CEMS response

value from the correlation test that corresponds to the

minimum value for ) must be within 10 percent of the PM

emission limit value specified in the applicable

regulation, as calculated using Equation 11-28.

(iii) For exponential or power correlations, the 95

percent confidence interval half range at the median PM

CEMS response value from the correlation test must be

within 10 percent of the natural logarithm of the PM

emission limit value specified in the applicable

regulation, as calculated using Equation 11-40.

(3) The tolerance interval half range must satisfy

the applicable criterion specified in paragraph (3)(i),

(ii), or (iii) of this section, based on the type of

correlation model. 

(i) For linear or logarithmic correlations, the

tolerance interval half range at the mean PM CEMS response

value from the correlation test must have 95 percent

confidence that 75 percent of all possible values are

within 25 percent of the PM emission limit value specified

in the applicable regulation, as calculated using Equation

11-13.

(ii) For polynomial correlations, the tolerance

interval half range at the PM CEMS response value from the
correlation test that corresponds to the minimum value for

) must have 95 percent confidence that 75 percent of all

possible values are within 25 percent of the PM emission

limit value specified in the applicable regulation, as

calculated using Equation 11-32.

(iii) For exponential or power correlations, the

tolerance interval half range at the median PM CEMS

response value from the correlation test must have 95

percent confidence that 75 percent of all possible values

are within 25 percent of the natural logarithm of the PM

emission limit value specified in the applicable

regulation, as calculated using Equation 11-41.

13.3 What are the sampling periods and

cycle/response time? You must document and maintain the

response time and any changes in the response time

following installation. 

(1) If you have a batch sampling PM CEMS, you must

evaluate the limits presented in paragraphs (1)(i) and

(ii) of this section.

(i) The response time of your PM CEMS, which is

equivalent to the cycle time, must be no longer than 15

minutes. In addition, the delay between the end of the

sampling time and reporting of the sample analysis must be

no greater than 3 minutes. You must document any changes

in the response time following installation.

(ii) The sampling time of your PM CEMS must be no

less than 30 percent of the cycle time. If you have a

batch sampling PM CEMS, sampling must be continuous except

during pauses when the collected pollutant on the capture

media is being analyzed and the next capture medium starts

collecting a new sample.

13.4 What PM compliance monitoring must I do? You

must report your CEMS measurements in the units of the

standard expressed in the regulations (e.g., mg/dscm @ 7

percent oxygen, pounds per million Btu (lb/mmBtu), etc.). 

You may need to install auxiliary data monitoring

equipment to convert the units reported by your PM CEMS

into units of the PM emission standard.

14.0 Pollution Prevention. [Reserved]

15.0 Waste Management. [Reserved]

16.0 Which references are relevant to this performance

specification?

16.1 Technical Guidance Document: Compliance

Assurance Monitoring. U.S. Environmental Protection

Agency Office of Air Quality Planning and Standards

Emission Measurement Center. August 1998.

16.2 40 CFR 60, Appendix B, "Performance

Specification 2 - Specifications and Test Procedures for
SO2 and NOx, Continuous Emission Monitoring Systems in

Stationary Sources."

16.3 40 CFR 60, Appendix B, "Performance

Specification 1 - Specification and Test Procedures for

Opacity Continuous Emission Monitoring Systems in

Stationary Sources."

16.4 40 CFR 60, Appendix A, "Method 1 - Sample and

Velocity Traverses for Stationary Sources."

16.5 "Current Knowledge of Particulate Matter (PM)

Continuous Emission Monitoring." EPA-454/R-00-039. U.S.

Environmental Protection Agency, Research Triangle Park,

NC. September 2000.

16.6 40 CFR 266, Appendix IX, Section 2,

"Performance Specifications for Continuous Emission

Monitoring Systems."

16.7 ISO 10155, "Stationary Source Emissions -

Automated Monitoring of Mass Concentrations of Particles:

Performance Characteristics, Test Procedures, and

Specifications." American National Standards Institute,

New York City. 1995.

17.0 What reference tables and validation data are

relevant to PS-11? 

Use the information in Table 1 for determining the

confidence and tolerance interval half ranges. Use Table

2 to record your 7-day drift test data.

TABLE 1. FACTORS FOR CALCULATION OF CONFIDENCE

AND TOLERANCE INTERVAL HALF RANGES

df or n' tdf vdf un' (75)

2 4.303 4.415 1.433

3 3.182 2.920 1.340

4 2.776 2.372 1.295

5 2.571 2.089 1.266

6 2.447 1.915 1.247

7 2.365 1.797 1.233

8 2.306 1.711 1.223

9 2.262 1.645 1.214

10 2.228 1.593 1.208

11 2.201 1.551 1.203

12 2.179 1.515 1.199

13 2.160 1.485 1.195

14 2.145 1.460 1.192

15 2.131 1.437 1.189

16 2.120 1.418 1.187

17 2.110 1.400 1.185
18 2.101 1.385 1.183

19 2.093 1.370 1.181

20 2.086 1.358 1.179

21 2.080 1.346 1.178

22 2.074 1.335 1.177

23 2.069 1.326 1.175

24 2.064 1.317 1.174

25 2.060 1.308 1.173

26 2.056 1.301 1.172

27 2.052 1.294 1.172

28 2.048 1.287 1.171

29 2.045 1.281 1.171

30 2.042 1.274 1.170

31 2.040 1.269 1.169

32 2.037 1.264 1.169

33 2.035 1.258 1.168

34 2.032 1.253 1.168

35 2.030 1.248 1.167

36 2.028 1.244 1.167

37 2.026 1.240 1.166

38 2.025 1.236 1.166

39 2.023 1.232 1.165

40 2.021 1.228 1.165

41 2.020 1.225 1.165

42 2.018 1.222 1.164

43 2.017 1.219 1.164

44 2.015 1.216 1.163

45 2.014 1.213 1.163

46 2.013 1.210 1.163

47 2.012 1.207 1.163

48 2.011 1.205 1.162

49 2.010 1.202 1.162

50 2.009 1.199 1.162

51 2.008 1.197 1.162

52 2.007 1.194 1.162

53 2.006 1.191 1.161

54 2.005 1.189 1.161

55 2.005 1.186 1.161

56 2.004 1.183 1.161

57 2.003 1.181 1.161
58 2.002 1.178 1.160

59 2.001 1.176 1.160

60 2.000 1.173 1.160

61 2.000 1.170 1.160

62 1.999 1.168 1.160

63 1.999 1.165 1.159

TABLE 2. 7-DAY DRIFT TEST DATA

Zero

Drift

Day #

Date

and

Time

Zero Check

Value

(RL)

PM CEMS

Response

(RCEMS)

Difference

(RCEMS -

RL)

Zero Drift

((RCEMS-RL)/RU)×100

1

2

3

4

5

6

7

Upscale

Drift

Day #

Date

and

Time

Upscale

Check

Value

(RU)

PM CEMS

Response

(RCEMS)

Difference

(RCEMS -

RU)

Upscale Drift

((RCEMSRU)/RU)×100%

1

2

3

4

5

6

7

3. Appendix F, part 60 is revised to read as

follows:
APPENDIX F - QUALITY ASSURANCE PROCEDURES

* * * * *

PROCEDURE 2 - Quality Assurance Requirements for

Particulate Matter Continuous Emission Monitoring Systems

at Stationary Sources

1.0 What are the purpose and applicability of Procedure

2?

The purpose of Procedure 2 is to establish the

minimum requirements for evaluating the effectiveness of

quality control (QC) and quality assurance (QA) procedures

and the quality of data produced by your particulate

matter (PM) continuous emission monitoring system (CEMS). 

Procedure 2 applies to PM CEMS used for continuously

determining compliance with emission standards or

operating permit limits as specified in an applicable

regulation or permit. Other QC procedures may apply to

diluent (e.g., O2) monitors and other auxiliary monitoring

equipment included with your CEMS to facilitate PM

measurement or determination of PM concentration in units

specified in an applicable regulation.

1.1 What measurement parameter does Procedure 2

address? Procedure 2 covers the instrumental measurement

of PM as defined by your source’s applicable reference

method (no Chemical Abstract Service number assigned).
1.2 For what types of devices must I comply with

Procedure 2? You must comply with Procedure 2 for the

total equipment that: 

(1) We require you to install and operate on a

continuous basis under the applicable regulation, and 

(2) You use to monitor the PM mass concentration

associated with the operation of a process or emission

control device.

1.3 What are the data quality objectives (DQOs) of

Procedure 2? The overall DQO of Procedure 2 is the

generation of valid, representative data that can be

transferred into useful information for determining PM

CEMS concentrations averaged over a prescribed interval. 

Procedure 2 is also closely associated with Performance

Specification 11 (PS-11).

(1) Procedure 2 specifies the minimum requirements

for controlling and assessing the quality of PM CEMS data

submitted to us or the delegated permitting authority. 

(2) You must meet these minimum requirements if you

are responsible for one or more PM CEMS used for

compliance monitoring. We encourage you to develop and

implement a more extensive QA program or to continue such

programs where they already exist. 

1.4 What is the intent of the QA/QC procedures
specified in Procedure 2? Procedure 2 is intended to

establish the minimum QA/QC requirements for PM CEMS and

is presented in general terms to allow you to develop a

program that is most effective for your circumstances. 

You may adopt QA/QC procedures that go beyond these

minimum requirements to ensure compliance with applicable

regulations.

1.5 When must I comply with Procedure 2? You must

comply with the basic requirements of Procedure 2

immediately following successful completion of the initial

correlation test of PS-11.

2.0 What are the basic requirements of Procedure 2?

Procedure 2 requires you to perform periodic

evaluations of PM CEMS performance and to develop and

implement QA/QC programs to ensure that PM CEMS data

quality is maintained. 

2.1 What are the basic functions of Procedure 2?

(1) Assessment of the quality of your PM CEMS data

by estimating measurement accuracy;

(2) Control and improvement of the quality of your

PM CEMS data by implementing QC requirements and

corrective actions until the data quality is acceptable;

and

(3) Specification of requirements for daily
instrument zero and upscale drift checks and daily sample

volume checks, as well as routine response correlation

audits, absolute correlation audits, sample volume audits,

and relative response audits. 

3.0 What special definitions apply to Procedure 2?

The definitions in Procedure 2 include those provided

in PS-11 of Appendix B, with the following additions:

3.1 "Absolute Correlation Audit (ACA)" means an

evaluation of your PM CEMS response to a series of

reference standards covering the full measurement range of

the instrument (e.g., 4 mA to 20 mA). 

3.2 "Correlation Range" means the range of PM CEMS

responses used in the complete set of correlation test

data.

3.3 "PM CEMS Correlation" means the site-specific

relationship (i.e., a regression equation) between the

output from your PM CEMS (e.g., mA) and the particulate

concentration, as determined by the reference method. The

PM CEMS correlation is expressed in the same units as the

PM concentration measured by your PM CEMS (e.g., mg/acm). 

You must derive this relation from PM CEMS response data

and manual reference method data that were gathered

simultaneously. These data must be representative of the

full range of source and control device operating
conditions that you expect to occur. You must develop the

correlation by performing the steps presented in sections

12.2 and 12.3 of PS-11.

3.4 "Reference Method Sampling Location" means the

location in your source’s exhaust duct from which you

collect manual reference method data for developing your

PM CEMS correlation and for performing relative response

audits (RRAs) and response correlation audits (RCAs).

3.5 "Response Correlation Audit (RCA)" means the

series of tests specified in section 10.3(8) of this

procedure that you conduct to ensure the continued

validity of your PM CEMS correlation.

3.6 "Relative Response Audit (RRA)" means the brief

series of tests specified in section 10.3(6) of this

procedure that you conduct between consecutive RCAs to

ensure the continued validity of your PM CEMS correlation.

3.7 "Sample Volume Audit (SVA)" means an evaluation

of your PM CEMS measurement of sample volume if your PM

CEMS determines PM concentration based on a measure of PM

mass in an extracted sample volume and an independent

determination of sample volume.

4.0 Interferences. [Reserved]

5.0 What do I need to know to ensure the safety of

persons using Procedure 2?
People using Procedure 2 may be exposed to hazardous

materials, operations, and equipment. Procedure 2 does

not purport to address all of the safety issues associated

with its use. It is your responsibility to establish

appropriate safety and health practices and determine the

applicable regulatory limitations before performing this

procedure. You must consult your CEMS user’s manual for

specific precautions to be taken with regard to your PM

CEMS procedures.

6.0 What equipment and supplies do I need?

[Reserved]

7.0 What reagents and standards do I need?

You will need reference standards or procedures to

perform the zero drift check, the upscale drift check, and

the sample volume check.

7.1 What is the reference standard value for the

zero drift check? You must use a zero check value that is

no greater than 20 percent of the PM CEMS’s response

range. You must obtain documentation on the zero check

value from your PM CEMS manufacturer.

7.2 What is the reference standard value for the

upscale drift check? You must use an upscale check value

that produces a response between 50 and 100 percent of the

PM CEMS’s response range. For a PM CEMS that produces
output over a range of 4 mA to 20 mA, the upscale check

value must produce a response in the range of 12 mA to 20

mA. You must obtain documentation on the upscale check

value from your PM CEMS manufacturer.

7.3 What is the reference standard value for the

sample volume check? You must use a reference standard

value or procedure that produces a sample volume value

equivalent to the normal sampling rate. You must obtain

documentation on the sample volume value from your PM CEMS

manufacturer.

8.0 What sample collection, preservation, storage, and

transport are relevant to this procedure?

[Reserved]

9.0 What quality control measures are required by this

procedure for my PM CEMS?

You must develop and implement a QC program for your

PM CEMS. Your QC program must, at a minimum, include

written procedures that describe, in detail, complete

step-by-step procedures and operations for the activities

in paragraphs (1) through (8) of this section.

(1) Procedures for performing drift checks,

including both zero drift and upscale drift and the sample

volume check (see sections 10.2(1), (2), and (5)).

(2) Methods for adjustment of PM CEMS based on the
results of drift checks, sample volume checks (if

applicable), and the periodic audits specified in this

procedure.

(3) Preventative maintenance of PM CEMS (including

spare parts inventory and sampling probe integrity).

(4) Data recording, calculations, and reporting.

(5) RCA and RRA procedures, including sampling and

analysis methods, sampling strategy, and structuring test

conditions over the prescribed range of PM concentrations.

(6) Procedures for performing ACAs and SVAs and

methods for adjusting your PM CEMS response based on ACA

and SVA results. 

(7) Program of corrective action for malfunctioning

PM CEMS, including flagged data periods.

(8) For extractive PM CEMS, procedures for checking

extractive system ducts for material accumulation.

9.1 What QA/QC documentation must I have? You are

required to keep the written QA/QC procedures on record

and available for inspection by us, the State, and/or

local enforcement agency for the life of your CEMS or

until you are no longer subject to the requirements of

this procedure.

9.2 How do I know if I have acceptable QC procedures

for my PM CEMS? Your QC procedures are inadequate or your
PM CEMS is incapable of providing quality data if you fail

two consecutive QC audits (i.e., out-of-control conditions

resulting from the annual audits, quarterly audits, or

daily checks). Therefore, if you fail the same two

consecutive audits, you must revise your QC procedures or

modify or replace your PM CEMS to correct the deficiencies

causing the excessive inaccuracies (see section 10.4 for

limits for excessive audit inaccuracy).

10.0 What calibration/correlation and standardization

procedures must I perform for my PM CEMS?

You must generate a site-specific correlation for

each of your PM CEMS installation(s) relating response

from your PM CEMS to results from simultaneous PM

reference method testing. The PS-11 defines procedures

for developing the correlation and defines a series of

statistical parameters for assessing acceptability of the

correlation. However, a critical component of your PM

CEMS correlation process is ensuring the accuracy and

precision of reference method data. The activities listed

in sections 10.1 through 10.10 assure the quality of the

correlation.

10.1 When should I use paired trains for reference

method testing? Although not required, we recommend that

you should use paired-train reference method testing to
generate data used to develop your PM CEMS correlation and

for RCA testing. Guidance on the use of paired sampling

trains can be found in the PM CEMS Knowledge Document (see

section 16.5).

10.2 What routine system checks must I perform on my

PM CEMS? You must perform routine checks to ensure proper

operation of system electronics and optics, light and

radiation sources and detectors, and electric or electromechanical systems. Necessary components of the routine

system checks will depend on design details of your PM

CEMS. As a minimum, you must verify the system operating

parameters listed in paragraphs (1) through (5) of this

section on a daily basis. Some PM CEMS may perform one or

more of these functions automatically or as an integral

portion of unit operations; for other PM CEMS, you must

initiate or perform one or more of these functions

manually.

(1) You must check the zero drift to ensure

stability of your PM CEMS response to the zero check

value. You must determine system output on the most

sensitive measurement range when the PM CEMS is challenged

with a zero reference standard or procedure. You must, at

a minimum, adjust your PM CEMS whenever the daily zero

drift exceeds 4 percent.
(2) You must check the upscale drift to ensure

stability of your PM CEMS response to the upscale check

value. You must determine system output when the PM CEMS

is challenged with a reference standard or procedure

corresponding to the upscale check value. You must, at a

minimum, adjust your PM CEMS whenever the daily upscale

drift check exceeds 4 percent.

(3) For light-scattering and extinction-type PM

CEMS, you must check the system optics to ensure that

system response has not been altered by the condition of

optical components, such as fogging of lens and

performance of light monitoring devices.

(4) You must record data from your automatic driftadjusting PM CEMS before any adjustment is made. If your

PM CEMS automatically adjusts its response to the

corrected calibration values (e.g., microprocessor

control), you must program your PM CEMS to record the

unadjusted concentration measured in the drift check

before resetting the calibration. Alternately, you may

program your PM CEMS to record the amount of adjustment.

(5) For extractive PM CEMS that measure the sample

volume and use the measured sample volume as part of

calculating the output value, you must check the sample

volume on a daily basis to verify the accuracy of the
sample volume measuring equipment. This sample volume

check must be done at the normal sampling rate of your PM

CEMS. You must adjust your PM CEMS sample volume

measurement whenever the daily sample volume check error

exceeds 10 percent.

10.3 What are the auditing requirements for my PM

CEMS? You must subject your PM CEMS to an ACA and an SVA,

as applicable, at least once each calender quarter. 

Successive quarterly audits must occur no closer than 2

months apart. You must conduct an RCA and an RRA at the

frequencies specified in the applicable regulation or

facility operating permit. An RRA or RCA conducted during

any calendar quarter can take the place of the ACA

required for that calendar quarter. An RCA conducted

during the period in which an RRA is required can take the

place of the RRA for that period. 

(1) When must I perform an ACA? You must perform an

ACA each quarter unless you conduct an RRA or RCA during

that same quarter.

(2) How do I perform an ACA? You perform an ACA

according to the procedure specified in paragraphs (2)(i)

through (v) of this section.

(i) You must challenge your PM CEMS with an audit

standard or an equivalent audit reference to reproduce the
PM CEMS’s measurement at three points within the following

ranges:

Audit point Audit range

1 0 to 20 percent of measurement range

2 40 to 60 percent of measurement range

3 70 to 100 percent of measurement range

(ii) You must then challenge your PM CEMS three

times at each audit point and use the average of the three

responses in determining accuracy at each audit point. 

Use a separate audit standard for audit points 1, 2, and

3. Challenge the PM CEMS at each audit point for a

sufficient period of time to ensure that your PM CEMS

response has stabilized.

(iii) Operate your PM CEMS in the mode, manner, and

range specified by the manufacturer.

(iv) Store, maintain, and use audit standards as

recommended by the manufacturer. 

(v) Use the difference between the actual known

value of the audit standard and the response of your PM

CEMS to assess the accuracy of your PM CEMS.

(3) When must I perform an SVA? You must perform an

audit of the measured sample volume (e.g., the sampling

flow rate for a known time) once per quarter for

applicable PM CEMS with an extractive sampling system. 
Also, you must perform and pass an SVA prior to initiation

of any of the reference method data collection runs for an

RCA or RRA. 

(4) How do I perform an SVA? You perform an SVA

according to the procedure specified in paragraphs (4)(i)

through (iii) of this section. 

(i) You perform an SVA by independently measuring

the volume of sample gas extracted from the stack or duct

over each batch cycle or time period with a calibrated

device. You may make this measurement either at the inlet

or outlet of your PM CEMS, so long as it measures the

sample gas volume without including any dilution or

recycle air. Compare the measured volume with the volume

reported by your PM CEMS for the same cycle or time period

to calculate sample volume accuracy. 

(ii) You must make measurements during three

sampling cycles for batch extractive monitors (e.g., Betagauge) or during three periods of at least 20 minutes for

continuous extractive PM CEMS. 

(iii) You may need to condense, collect, and measure

moisture from the sample gas prior to the calibrated

measurement device (e.g., dry gas meter) and correct the

results for moisture content. In any case, the volumes

measured by the calibrated device and your PM CEMS must be
on a consistent temperature, pressure, and moisture basis.

(5) How often must I perform an RRA? You must

perform an RRA at the frequency specified in the

applicable regulation or facility operating permit. You

may conduct an RCA instead of an RRA during the period

when the RRA is required.

(6) How do I perform an RRA? You must perform the

RRA according to the procedure specified in paragraphs

(6)(i) and (ii) of this section.

(i) You perform an RRA by collecting three

simultaneous reference method PM concentration

measurements and PM CEMS measurements at the as-found

source operating conditions and PM concentration. 

(ii) We recommend that you use paired trains for

reference method sampling. Guidance on the use of paired

sampling trains can be found in the PM CEMS Knowledge

Document (see section 16.5 of PS-11).

(7) How often must I perform an RCA? You must

perform an RCA at the frequency specified in the

applicable regulation or facility operating permit. 

(8) How do I perform an RCA? You must perform the

RCA according to the procedures for the PM CEMS

correlation test described in PS-11, section 8.6, except

that the minimum number of runs required is 12 in the RCA
instead of 15 as specified in PS-11. 

(9) What other alternative audits can I use? You

can use other alternative audit procedures as approved by

us, the State, or local agency for the quarters when you

would conduct ACAs.

10.4 What are my limits for excessive audit

inaccuracy? Unless specified otherwise in the applicable

subpart, the criteria for excessive audit inaccuracy are

listed in paragraphs (1) through (6) of this section.

(1) What are the criteria for excessive zero or

upscale drift? Your PM CEMS is out of control if the zero

drift check or upscale drift check either exceeds 4

percent for five consecutive daily periods or exceeds 8

percent for any one day. 

(2) What are the criteria for excessive sample

volume measurement error? Your PM CEMS is out of control

if sample volume check error exceeds 10 percent for five

consecutive daily periods or exceeds 20 percent for any

one day. 

(3) What are the criteria for excessive ACA error? 

Your PM CEMS is out of control if the results of any ACA

exceed ± 10 percent of the average audit value or 7.5

percent of the applicable standard, whichever is greater.

(4) What is the criterion for excessive SVA error? 
Your PM CEMS is out of control if results exceed ± 5

percent of the average sample volume audit value.

(5) What are the criteria for passing an RCA? To

pass an RCA, you must meet the criteria specified in

paragraphs (5)(i) through (iii) of this section. If your

PM CEMS fails to meet these RCA criteria, it is out of

control.

(i) For all 12 data points, the PM CEMS response

value can be no greater than the greatest PM CEMS response

value used to develop your correlation curve.

(ii) For 9 of the 12 data points, the PM CEMS

response value must lie within the PM CEMS output range

used to develop your correlation curve.

(iii) At least 75 percent of a minimum number of 12

sets of PM CEMS and reference method measurements must

fall within a specified area on a graph of the correlation

regression line. The specified area on the graph of the

correlation regression line is defined by two lines

parallel to the correlation regression line, offset at a

distance of ± 25 percent of the numerical emission limit

value from the correlation regression line.

(6) What are the criteria to pass an RRA? To pass

an RRA, you must meet the criteria specified in paragraphs

(6)(i) and (ii) of this section. If your PM CEMS fails to
meet these RRA criteria, it is out of control.

(i) For all three data points, the PM CEMS response

value can be no greater than the greatest PM CEMS response

value used to develop your correlation curve.

(ii) For two of the three data points, the PM CEMS

response value must lie within the PM CEMS output range

used to develop your correlation curve.

(iii) At least two of the three sets of PM CEMS and

reference method measurements must fall within the same

specified area on a graph of the correlation regression

line as required for the RCA and described in paragraph

(5)(iii) of this section.

10.5 What do I do if my PM CEMS is out of control? 

If your PM CEMS is out of control, you must take the

actions listed in paragraphs (1) and (2) of this section. 

(1) You must take necessary corrective action to

eliminate the problem and perform tests, as appropriate,

to ensure that the corrective action was successful. 

(i) Following corrective action, you must repeat the

previously failed audit to confirm that your PM CEMS is

operating within the specifications. 

(ii) If your PM CEMS failed an RRA, you must take

corrective action until your PM CEMS passes the RRA

criteria. If the RRA criteria cannot be achieved, you
must perform an RCA.

(iii) If your PM CEMS failed an RCA, you must follow

procedures specified in section 10.6 of this procedure.

(2) You must report both the audit showing your PM

CEMS to be out of control and the results of the audit

following corrective action showing your PM CEMS to be

operating within specifications.

10.6 What do I do if my PM CEMS fails an RCA? After

an RCA failure, you must take all applicable actions

listed in paragraphs (1) through (3) of this section.

(1) Combine RCA data with data from the active PM

CEMS correlation and perform the mathematical evaluations

defined in PS-11 for development of a PM CEMS correlation,

including examination of alternate correlation models

(i.e., linear, polynomial, logarithmic, exponential, and

power). If the expanded data base and revised correlation

meet PS-11 statistical criteria, use the revised

correlation.

(2) If the criteria specified in paragraph (1) of

this section are not achieved, you must develop a new PM

CEMS correlation based on revised data. The revised data

set must consist of the test results from only the RCA. 

The new data must meet all requirements of PS-11 to

develop a revised PM CEMS correlation, except that the
minimum number of sets of PM CEMS and reference method

measurements is 12 instead of the minimum of 15 sets

required by PS-11. Your PM CEMS is considered to be back

in controlled status when the revised correlation meets

all of the performance criteria specified in section 13.2

of PS-11.

(3) If the actions in paragraphs (1) and (2) of this

section do not result in an acceptable correlation, you

must evaluate the cause(s) and comply with the actions

listed in paragraphs (3)(i) through (iv) of this section

within 90 days after the completion of the failed RCA.

(i) Completely inspect your PM CEMS for mechanical

or operational problems. If you find a mechanical or

operational problem, repair your PM CEMS and repeat the

RCA.

(ii) You may need to relocate your PM CEMS to a more

appropriate measurement location. If you relocate your PM

CEMS, you must perform a new correlation test according to

the procedures specified in PS-11.

(iii) The characteristics of the PM or gas in your

source’s flue gas stream may have changed such that your

PM CEMS measurement technology is no longer appropriate. 

If this is the case, you must install a PM CEMS with

measurement technology that is appropriate for your
source’s flue gas characteristics. You must perform a new

correlation test according to the procedures specified in

PS-11.

(iv) If the corrective actions in paragraphs (3)(i)

through (iii) of this section were not successful, you

must petition us, the State, or local agency for approval

of alternative criteria or an alternative for continuous

PM monitoring.

10.7 When does the out-of-control period begin

and end? The out-of-control period begins immediately

after the last test run or check of an unsuccessful RCA,

RRA, ACA, SVA, drift check, or sample volume check. The

out-of-control period ends immediately after the last test

run or check of the subsequent successful audit or drift

check.

10.8 Can I use the data recorded by my PM CEMS

during out-of-control periods? During any period when

your PM CEMS is out of control, you may not use your PM

CEMS data to calculate emission compliance or to meet

minimum data availability requirements described in the

applicable regulation.

10.9 What are the QA/QC reporting requirements for

my PM CEMS? You must report the accuracy results for your

PM CEMS, specified in section 10.4 of this procedure, at
the interval specified in the applicable regulation. 

Report the drift and accuracy information as a Data

Assessment Report (DAR), and include one copy of this DAR

for each quarterly audit with the report of emissions

required under the applicable regulation. An example DAR

is provided in Procedure 1, Appendix F of this part.

10.10 What minimum information must I include in my

DAR? As a minimum, you must include the information

listed in paragraphs (1) through (5) of this section in

the DAR:

(1) Your name and address.

(2) Identification and location of monitors in your

CEMS.

(3) Manufacturer and model number of each monitor in

your CEMS.

(4) Assessment of PM CEMS data

accuracy/acceptability, and date of assessment, as

determined by an RCA, RRA, ACA, or SVA described in

section 10, including the acceptability determination for

the RCA or RRA, the accuracy for the ACA or SVA, the

reference method results, the audit standards, your PM

CEMS responses, and the calculation results as defined in

section 12. If the accuracy audit results show your PM

CEMS to be out of control, you must report both the audit
results showing your PM CEMS to be out of control and the

results of the audit following corrective action showing

your PM CEMS to be operating within specifications.

(5) Summary of all corrective actions you took when

you determined your PM CEMS to be out of control, as

described in section 10.5, or after failing an RCA, as

described in section 10.6.

10.7 Where and how long must I retain the QA data

that this procedure requires me to record for my PM CEMS? 

You must keep the records required by this procedure for

your PM CEMS onsite and available for inspection by us,

the State, and/or local enforcement agency for a period of

5 years.

11.0 What analytical procedures apply to this procedure? 

Sample collection and analysis are concurrent for

this procedure. You must refer to the appropriate

reference method for the specific analytical procedures.

12.0 What calculations and data analysis must I perform

for my PM CEMS? 

(1) How do I determine RCA and RRA acceptability? 

You must plot each of your PM CEMS and reference method

data sets from an RCA or RRA on a graph based on your PM

CEMS correlation line to determine if the criteria in

paragraphs 10.4(5) or (6), respectively, are met.
(2) How do I calculate ACA accuracy? You must use

Equation 2-1 to calculate ACA accuracy for each of the

three audit points:

ACA Accuracy (Eq. 2-1)

R R

R

100 CEM V

V

=

−

×

where:

ACA Accuracy = The ACA accuracy at each audit point,

in percent,

RCEM = Your PM CEMS response to the reference

standard, and 

RV = The reference standard value. 

(3) How do I calculate daily upscale and zero drift? 

You must calculate the upscale drift using to Equation 2-2

and the zero drift according to Equation 2-3:

UD (Eq. 2-2)

R R

R

100 CEM U

U

=

−

×

where:

UD = The upscale drift of your PM CEMS, in

percent,

RCEM = Your PM CEMS response to the upscale check

value, and 
RU = The upscale check value.

ZD (Eq. 2-3)

R R

R

100 CEM L

U

=

−

×

where:

ZD = The zero (low-level) drift of your PM CEMS,

in percent,

RCEM = Your PM CEMS response of the zero check

value, 

RL = The zero check value, and

RU = The upscale check value. 

(4) How do I calculate SVA accuracy? You must use

Equation 2-4 to calculate the accuracy, in percent, for

each of the three SVA tests or the daily sample volume

check:

(Eq. 2-4)

( )

Accuracy 

V V

FS

100 R M=

−

×

where:

VM = Sample gas volume determined/reported by

your PM CEMS (e.g., dscm),

VR = Sample gas volume measured by the

independent calibrated reference device

(e.g., dscm) for the SVA or the reference
value for the daily sample volume check,

and

FS = Full-scale value.

Note: Before calculating SVA accuracy, you must

correct the sample gas volumes measured by your PM CEMS

and the independent calibrated reference device to the

same basis of temperature, pressure, and moisture content. 

You must document all data and calculations.

13.0 Method Performance. [Reserved]

14.0 Pollution Prevention. [Reserved]

15.0 Waste Management. [Reserved]

16.0 Which references are relevant to this method?

[Reserved]

17.0 What tables, diagrams, flowcharts, and validation

data are relevant to this method? [Reserved]