218 - 1

(Adopted January 9, 1976)(Amended April 1, 1977)(Amended August 5, 1977)

(Amended April 6, 1979)(Amended August 7, 1981)(Amended May 14, 1999)

RULE 218. CONTINUOUS EMISSION MONITORING

(a) Definitions

(1) ANALYZER- the part of the continuous emission monitoring system

(CEMS) that analyzes the appropriate gaseous constituents of the

conditioned gaseous sample or measures stack gas volumetric flow and

fuel flow rates, as applicable.

(A) Contaminant Analyzer - the part of the CEMS that detects the air

contaminant and represents those concentrations in a signal output.

(B) Diluent Analyzer - the part of the CEMS that detects oxygen,

carbon dioxide or other diluent gas concentrations and represents

those concentrations in a signal output.

(C) Fuel Flowmeter - the part of the CEMS that detects the parameters 

of all essential measurement sub-systems (e.g., temperature,

pressure, differential pressure, frequency, gas density, gas

composition, heating value) and generates signal outputs which are 

a function of the fuel flow rate and all essential measurement subsystem parameters. 

(D) Stack Flowmeter - the part of the CEMS that detects the

parameters from all essential measurement sub-systems (e.g.,

temperature, static and atmospheric pressure, gas density, gas

composition, molecular weight, gas moisture content) and

generates signal outputs which are a function of the stack gas

volumetric flow rate and all essential measurement sub-system 

parameters. 

(2) CALIBRATION - a procedure performed to ensure that the CEMS

accurately measures and record air contaminant or diluent gas

concentration, flow rate and other parameters necessary to generate data,

as evidenced by calibration checks, and achieved by periodic manual or

automatic adjustment.

(3) CALIBRATION CHECK - a procedure performed to determine the

CEMS response to a given gaseous compound concentration. A certified 
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 2

calibration gas mixture is injected into the CEMS as close to the probe tip 

as practical.

(4) CERTIFIED CEMS - a CEMS installed, tested, operated, maintained, and 

calibrated according to the applicable requirements of Rule 218; that has

met the applicable performance specifications according to

Rule 218(c)(1)(B), and, has received written approval and conditions

thereto applying, from the Executive Officer.

(5) CERTIFIED GAS MIXTURE - a gas mixture manufactured, analyzed and 

certified according to “EPA Traceability Protocol for Assay and

Certification of Gaseous Calibration Standards” - EPA-600/R97/121, 

September 1997 Revision (EPA Protocol) or any subsequent version

published by EPA. This definition incorporates by reference EPA

Protocol.

(6) CONTINUOUS EMISSION MONITORING SYSTEM (CEMS) - the

total combined equipment and systems required to continuously determine 

air contaminants and diluent gas concentrations and/or mass emission rate

of a source effluent (as applicable). The CEMS consists of three major

subsystems: sampling interface, analyzer and data acquisition system. 

(7) CONTINUOUS MONITORING - monitoring in which a minimum of one 

measurement (e.g., concentration, mass emission, flow rate) is taken and

recorded each minute.

(8) DATA ACQUISITION SYSTEM (DAS) - the part of the CEMS that

processes data generated by the analyzer and records the results, thus

creating a permanent record of the output signal in terms of concentration, 

flow rate, and/or any other applicable parameter necessary to generate the 

required data in units of applicable standard. The DAS consists of all

equipment such as a computer required to convert the original recorded

values to any values required for reporting.

(9) DILUENT GAS - a gas present in a calibration gas mixture or in the

source emissions which is present in quantities significantly larger than the 

air contaminant.

(10) LABORATORY APPROVAL PROGRAM (LAP) - a program

administered by the District that grants test-method-specific approvals to

independent testing laboratories or firms that perform tests to determine

source compliance with District rules and regulations.
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 3

(11) MODIFICATION REQUIRING RECERTIFICATION - any change to

the basic equipment, control equipment, contaminant concentration,

interfering substances, or CEMS (or SCEMS) that is deemed by the

Executive Officer to have a potential for adversely affecting the ability of

the CEMS to provide accurate, precise and timely data representative of

the stack emissions for which the CEMS (or SCEMS) is required. 

(12) QUALITY ASSURANCE/QUALITY CONTROL (QA/QC) PLAN - a

written document in which the specific procedures for the operation,

calibration and maintenance of a certified CEMS are described in detail,

including additional quality assurance assessments and the corrective action 

system. The purpose of this plan is to ensure that the CEMS generates,

collects and reports valid data that is precise, accurate, complete, and of a 

quality that meets the requirements, performance specifications, and

standards of Rules 218 and 218.1.

(13) ROUTINE MAINTENANCE - preventive evaluation and repair (if

necessary) of CEMS performed at specified intervals to preclude system

failure. Routine maintenance may be performed as recommended by the

manufacturer or a documented standard operating procedure determined

through operating experience and approved by the Executive Officer. 

Repairs to a malfunctioning system are excluded from this definition.

(14) SAMPLING INTERFACE - that part of the CEMS that performs sample

acquisition using one or more of the following operations: extraction,

physical/chemical separation, transportation or conditioning of a

representative sample from a designated source.

(15) SEMI-CONTINUOUS EMISSION MONITORING - a monitoring

technique in which a minimum of one measurement (e.g. concentration,

mass emission, flow rate) is taken and recorded every fifteen (15) minutes.

(16) SEMI-CONTINUOUS EMISSION MONITORING SYSTEM (SCEMS)

- the total combined equipment and systems to semi-continuously 

determine air contaminant and diluent gas concentrations and/or the mass

emission rate in a source effluent (as applicable) The system consists of

three major subsystems: sampling interface, analyzer and data acquisition

system. This class of monitoring includes but is not limited to gas

chromatography, integrated sensitized tape analyzer, other sample

integration based technologies, and time-shared CEMS.
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 4

(17) SYSTEM FAILURE - inability of the CEMS to meet the requirements of

Rule 218.1, “Continuous Emission Monitoring Performance

Specifications”, or, Code of Federal Regulations, Title 40 - "Protection of

Environment", Part 60 - "Standards of Performance for New Stationary

Sources", Appendix F - "Quality Assurance Procedures".

(18) TIME-SHARING - a monitoring technique where an analyzer and possibly 

the associated sample conditioning system is used on more than one

source.

(19) WORKING DAY - Monday through Friday excluding holidays.

(20) ZERO CHECK- a procedure performed to determine the response of the

CEMS to a given zero gas standard by means of injecting the zero gas into 

the CEMS as close to the probe tip as practical.

(21) ZERO GAS - a gas containing less than a specified amount of the air

contaminant or diluent gas which, when periodically injected into the

CEMS, is used to check CEMS’ response to the absence of the air

contaminant or diluent gas.

(b) Applicability and Monitoring Requirements for New, Modified and Existing

CEMS

(1) The provisions of this Rule shall apply to all sources that require CEMS as 

specified in the regulations or permit conditions, with the following

exceptions:

(A) This Rule shall not apply to CEMS subject to Regulation XX -

“Regional Clean Air Incentives Market (RECLAIM)”, Regulation

IX - “New Source Performance Standards (NSPS)”, Regulation X -

National Emission Standards for Hazardous Air Pollutants

(NESHAPS), or Regulation XXXI - "Acid Rain Program". 

(B) This Rule shall not apply to CEMS subject to permit conditions 

where the purpose of the CEMS is to monitor the performance of

the basic and/or control equipment and not to determine

compliance with any applicable limit or standard.

(C) This Rule shall not apply to CEMS where alternative performance

specifications are required by another District rule.

(2) The owner or operator of any equipment subject to this Rule shall provide, 

properly install, operate, and maintain in calibration and good working

order a certified CEMS to measure the concentration and/or emission 
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 5

rates, as applicable, of air contaminants and diluent gases, flow rates, and

other required parameters. The owner or operator shall also provide the

necessary records and other data necessary to calculate air contaminant

emission rates or concentrations, as specified in Rule 218, Sections (e) and 

(f).

(c) Requirements for New and Modified CEMS and SCEMS

(1) Application and Approval Requirements for New and Modified CEMS

(A) The owner or operator of any equipment subject to this Rule shall

submit to the Executive Officer an “Application for CEMS” or

“Application for CEMS Modification”, as applicable. Any

application submitted on or after May 14, 1999, shall require an

initial approval by the Executive Officer prior to installation of a new 

CEMS or modification of an existing CEMS. The Executive Officer 

shall notify the applicant in writing within 60 calendar days of receipt 

of an application for a new CEMS, or within 30 calendar days of

receipt of an application for a modification to an existing CEMS, if

the application contains sufficient information to be deemed

complete. Where an application has been determined to be

incomplete, the Executive Officer shall request specific information

needed to complete the application. Upon receipt of any complete

resubmittal or the additional information, plans or specifications

after the application has been deemed incomplete, a new 30-day 

period shall begin during which the Executive Officer shall determine 

the completeness of the application and notify the applicant. Within 

90 days of installation, a person operating or using CEMS shall

undertake a series of certification tests. If the equipment served by

the CEMS is not operating at the time of complete CEMS

installation, then the CEMS shall undergo a series of certification 

tests within 90 days from the next start-up of the equipment served 

by the CEMS. The purpose of the certification tests is to

demonstrate the CEMS performance pursuant to the specifications

in accordance with the provisions of Rule 218, Section (c)(1)(B). 

The owner or operator shall notify the Executive Officer in writing

at least 14 days before the scheduled certification test dates. The

certification tests shall be performed by a testing laboratory
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 6

approved under the District Laboratory Approval Program. Data

from such tests shall be submitted to the Executive Officer within 45 

days following test completion. If satisfactory performance is

demonstrated, final approval of the CEMS shall be granted.

Subsequent operation and maintenance of the certified CEMS shall

be in accordance with the provisions of Rule 218, Section (c)(1)(B). 

After final approval, modifications made to the CEMS shall be

reviewed and approved by the Executive Officer according to the

specifications stipulated in Rule 218, Section (c)(1)(B), and may

require all or a portion of performance tests to be conducted.

(B) Upon submission of an “Application for CEMS” or “Application for 

CEMS Modification” as prescribed in Rule 218 Section (c)(1)(A),

the applicant shall indicate either one of the following conditions:

(i) That the CEMS shall be reviewed and certified according to 

the provisions of Rule 218.1, “Continuous Emission

Monitoring Performance Specifications”, Section (b), and

the subsequent operation and maintenance of the certified

CEMS shall be in accordance with the provisions of Rule

218, Sections (b), (e), (f) and (g) and of the requirements of 

Rule 218.1(b) and (d), or,

(ii) That the CEMS shall be reviewed and certified according to 

the applicable provisions of the Code of Federal Regulations, 

Title 40 - "Protection of Environment", Part 60 - "Standards 

of Performance for New Stationary Sources" (40CFR60),

Appendix B - "Performance Specifications" (Appendix B),

and the subsequent operation and maintenance of the

certified CEMS shall be in accordance with the provisions of 

Rule 218, Sections (b), (e), (f) and (g), and the requirements 

of 40CFR60, Appendix F - "Quality Assurance Procedures"

(Appendix F).

Notwithstanding the requirements of Section (c)(1)(B)(ii),

any alternative test methods for 40CFR60, Appendices B and 

F shall be those that are listed in Rule 218.1, Table 1 -

Reference Methods.

(C) A "Notification of Pre-Approved Modification" and report of

results of prescribed quality assurance checks may be submitted in-
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 7

lieu of the "Application for CEMS Modification" when the

modification has been made in accordance with the written

technical guidance document approved by the Executive Officer.

(2) Application and Approval Requirements for New and Modified SCEMS

(A) In-lieu of submitting an application for CEMS per Rule 218,

Section (c)(1), the owner or operator of any equipment subject to 

this Rule, may elect to submit an application for a SCEMS if the

averaging time for the applicable limits(s) for which the CEMS is

required is 24 hours or greater; or, if the owner or operator

demonstrates, to the satisfaction of the Executive Officer, that no

CEMS technology is commercially available for the applicable

contaminant and the applicable limits.

(B) If the conditions in Rule 218, Section (c)(2)(A), above, do not

apply, the owner or operator of any equipment subject to this Rule 

may still elect to submit an application for a SCEMS in lieu of a

CEMS, subject to the following:

(i) The owner or operator demonstrates that the concentrations 

and/or emissions required to be monitored would be

equivalent to that monitored by a CEMS for the applicable

averaging period, to the satisfaction of the Executive

Officer;

(ii) The SCEMS shall be capable to take and record a minimum 

of one measurement (concentration, mass emission rate

and/or flow rate, as applicable) every 15 minutes allowing

as equally spaced data points as practical;

(iii) The owner or operator shall include in the QA/QC plan the 

method of calculating the 15-minute averages for

compliance determination to the applicable limit or

standard;

(iv) If an exeedance of the allowable limit or standard is

calculated using fewer than 100% valid data points, then the 

District shall use any relevant data for the operation of the

equipment (basic and control, as applicable) to verify the 

calculated exeedance;

(v) If a time shared SCEMS is proposed, it shall meet the

performance specifications of Rule 218.1, Section (e);
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 8

(C) The requirements for the application submittal and approval of

CEMS as provided in Rule 218, Section (c)(1) shall also apply for

SCEMS applications.

(3) Operation of CEMS or SCEMS During Certification Testing

CEMS or SCEMS shall be certified as configured for the normal operation 

of the CEMS or SCEMS with respect to sample acquisition, sample

conditioning, pollutant/diluent detection, data requirements and reporting.

(4) Quality Assurance/Quality Control Plan for New or Modified CEMS or

SCEMS

(A) The owner or operator of CEMS or SCEMS who elects the

performance specifications according to Rule 218, Section

(c)(1)(B)(i), shall submit to the Executive Officer for approval a

CEMS QA/QC Plan within 45 days of CEMS installation and no

later than 30 days before the certification tests.

(B) Alternative Quality Assurance Practices

The owner or operator of CEMS or SCEMS who elects the

performance specifications according to Rule 218, Section

(c)(1)(B)(i), may choose to develop alternative CEMS operational

test requirements to be included in the CEMS QA/QC procedures

that assure data of equivalent or better quality. These alternative

QA/QC procedures shall be submitted with the facility QA/QC Plan 

and are subject to the approval of the Executive Officer.

(d) Requirements for Existing CEMS and SCEMS

(1) Requirements for Existing CEMS

(A) A CEMS installed and granted final approval before May 14, 1999 

shall be maintained and operated according to the provisions of

Rule 218, Sections (b), (e), (f) and (g), and the requirements of

Rule 218.1, Sections (c) and (d). 

(B) A CEMS application for initial and final approval submitted to the

Executive Officer before May 14, 1999 shall be reviewed and

approved by the Executive Officer according to the specifications

and requirements of Rule 218.1, Sections (c) and (d). After final

approval, the CEMS shall be operated and maintained according to 

the provisions of Rule 218, Sections (b), (e), (f) and (g), and the

requirements of Rule 218.1, Sections (c) and (d).
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 9

(C) Modifications requiring recertification to any existing CEMS shall

be reviewed and approved according to the conditions under Rule

218 Section (c)(1)(B)(i) or (ii), as applicable. After final approval,

the modified CEMS shall be operated and maintained according to 

the conditions under Rule 218, Section (c)(1)(B)(i) or (ii), as

applicable.

(D) (i) All existing CEMS as prescribed in Rule 218, Sections

(d)(1)(A) and (B) shall comply with the provisions of Rule

218.1, Sections (b) and (d), or 40CFR60 Appendices B and 

F, as applicable, and of Rule 218, Sections (b) and (c), no

later than May 14, 2006.

(ii) The requirements of Rule 218, Section (d)(1)(D)(i) shall be 

waived for a period of three years if the owner or operator 

demonstrates, to the satisfaction of the Executive Officer, 

that the existing CEMS is providing data that are of a

quality commensurate with the original performance

specifications and other indicators of consistent data quality. 

Data quality factors that will be considered include:

(I) Relative Accuracy

(II) Calibration Error

(III) Calibration Drift

(IV) Zero Drift

(V) Valid data return percentage

(VI) Availability or up-time percentage

(VII) Breakdown frequency and duration

(VIII) Excursions beyond quality control limits in QA plan.

The owner or operator may apply for a waiver under this

sub-section every three years after May 14, 2006. This subsection shall not apply to existing CEMS that are required

to comply with the provisions of Rule 218.1, Sections (b)

and (d), or, 40 CFR60, Appendices B and F, as applicable, 

and Rule 218, Sections (b) and (c), as a result of CEMS

modifications requiring recertification, rule implementation,

or, compliance with a permit condition.

(E) The owner or operator of existing CEMS shall develop and

implement a written Quality Assurance/ Quality Control (QA/QC)
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 10

Plan no later than May 14, 2000. The written QA/QC Plan shall be 

kept on record and available for inspection upon request by the

Executive Officer. 

(F) On or before May 14, 2005, the owner or operator of any existing 

CEMS shall submit to the Executive Officer for approval: 

(i) A certification signed by an authorized representative of the 

facility that the existing CEMS meets the requirements of

Rule 218, Section (c), or,

(ii) An “Application for CEMS Modification”, with the

applicable fee(s) as specified in Rule 301, or,

(iii) An application for waiver according to Rule 218, Section

(d)(1)(D)(i), with documentation supporting the required

demonstration;

(2) Requirements for Existing SCEMS

(A) A SCEMS installed and granted final approval before May 14, 1999 

shall be maintained and operated according to the provisions of

Rule 218, Sections (b), (e), (f) and (g), and the requirements of

Rule 218.1, Sections (c) and (d). 

(B) A SCEMS application for initial and final approval submitted to the 

Executive Officer before May 14, 1999 shall be reviewed and

approved by the Executive Officer according to the specifications

and requirements of Rule 218.1, Sections (c) and (d). After final

approval, the SCEMS shall be operated and maintained according

to the provisions of Rule 218, Sections (b), (e), (f) and (g), and the 

requirements of Rule 218.1, Sections (c) and (d).

(C) Modifications requiring recertification to any existing SCEMS shall

be reviewed and approved according to the conditions under Rule

218 Section (c)(1)(B)(i) or (ii), as applicable. After final approval,

the modified CEMS shall be operated and maintained according to 

the conditions under Rule 218, Section (c)(1)(B)(i) or (ii), as

applicable.

(D) The owner or operator of an existing SCEMS operating on or

before May 14, 1999 shall be required to comply with the

provisions of Rule 218.1 Section (e) - “Time Sharing

Requirements” and with the provisions of Rule 218.1 Sections (b)
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 11

and (d), or, 40CFR60 Appendix B and F, as applicable, when the

equipment served by the time-shared SCEMS is modified such that:

(i) One or more of the sources monitored requires a new

monitoring range,

(ii) The operating permit is modified to require continuous

monitoring, or, 

(iii) An applicable source specific rule is adopted or revised to

require continuous monitoring.

Subsequent operation and maintenance of the SCEMS shall be

according to the provisions of Rule 218, Section (c)(1)(B)(i) or (ii), 

as applicable. 

(e) Retention of Records for New, Modified and Existing CEMS and SCEMS

(1) The records of the data obtained from the CEMS recording devices shall

clearly indicate concentrations or emission rates, or both, as specified by

the Executive Officer. Records shall be maintained by the CEMS owner or 

operator for a minimum period of two years, unless otherwise specifically

provided by another District regulation or permit conditions, and, shall be

made available to the Executive Officer upon request.

(2) All calculations, raw parameter data used for calculations, records of the

occurrence and duration of any start up, shutdown or malfunction,

performance test, evaluation, calibration, adjustment and maintenance of

the CEMS as well as calibration gas traceability shall be retained by the 

CEMS operator for a minimum period of two years unless otherwise

specifically provided by another District regulation or permit conditions,

and shall be made available to the Executive Officer upon request.

(f) Reporting Requirements for New, Modified and Existing CEMS and SCEMS

Unless otherwise specifically provided by another District regulation or permit

conditions, the following reporting requirements shall apply to new, modified and 

existing CEMS and SCEMS:

(1) A CEMS owner or operator shall provide a summary of the concentration 

and/or emission rate data, as applicable, obtained from the CEMS, as well

as any additional information specified by the Executive Officer, to

evaluate the accuracy and precision of the measurements. The summary

shall be submitted once every six months to the Executive Officer, except 
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 12

when more frequent reporting is specifically required by another District

rule, or the Executive Officer, on a case-by-case basis, determines that

more frequent reporting is necessary to accurately assess the compliance

status of the source. The summary report shall be submitted within 30 days 

following the end of the six-month period being reported, in the form and 

manner prescribed by the Executive Officer. The summary shall be

maintained on-site in a retrievable and readable form and shall be made

available to the Executive Officer upon request. The submitted summaries 

shall be available for public inspection at the District.

(2) The CEMS owner or operator shall report any concentration level and/or 

emission rate, as applicable, in excess of the regulated limit within 24 hours 

or the next working day after such occurrence in the form and manner

prescribed by the Executive Officer. The report shall include the following 

information:

(A) Time intervals, date, and magnitude of the excess concentration

level, nature and cause of the excess concentration (if known),

corrective action(s) taken, preventive measure(s) adopted, specific

location of CEMS, the equipment or CEMS involved and the

facility contact person.

(B) The averaging period used for data reporting shall correspond to

the averaging period specified in the rule or permit condition

governing the concentration and/or emission rate, if applicable.

(3) Reports of CEMS Failure or Shutdown

(A) The CEMS owner or operator shall notify the Executive Officer

within 24 hours or the next working day, in the event of a system

failure or shutdown, which exceeds 24 hours. Zero and calibration 

checks and routine maintenance do not require reporting.

(B) In the case of a CEMS failure or shutdown, compliance with the

provisions of Rule 218, Section (b) is waived for a period not to

exceed 96 consecutive hours. Such waiver is extended beyond 96 

consecutive hours only if a petition for an interim variance is filed in 

accordance with Regulation V and shall terminate at the time the

Hearing Board acts upon such variance petition. CEMS owners or 

operators of qualified facilities may obtain a Hearing Board

approval of an alternative operating condition following the
Rule 218 (Cont.) (Amended May 14, 1999)

218 - 13

established procedure in District Rule 518.2 - Federal Alternative

Operating Condition.

(C) Regularly scheduled CEMS maintenance shall be deferred until the

report required under Rule 218, Section (f)(2) is made, if the

system is measuring a concentration equal to or exceeding the

emission standard, and if such deferral is not reasonably expected to 

result in damage to the system.

(D) Continuous emission monitoring requirements shall not apply

during regular calibration checks of the system, or routine 

maintenance and repair lasting 60 minutes or less.

(g) Posting of Written Approval for New, Modified and Existing CEMS and SCEMS

The CEMS owner or operator of an approved CEMS shall affix a written notice of 

approval or a legible facsimile thereof, upon the equipment or within 26 feet of the 

equipment as prescribed in District Rule 206, in a manner such that it is clearly

visible, legible, and safely accessible. In the event that the equipment is

constructed or operated that the notice of approval or its legible facsimile cannot 

be so placed, such notice or legible facsimile shall be mounted on a location

approved by the Executive Officer.
404 - 1

(Adopted May 7, 1976)(Amended October 5, 1979)

(Amended February 7, 1986)

RULE 404. PARTICULATE MATTER - CONCENTRATION

(a) A person shall not discharge into the atmosphere from any source, particulate

matter in excess of the concentration at standard conditions, shown in Table

404(a).

Where the volume discharged is between figures listed in the Table, the exact

concentration permitted to be discharged shall be determined by linear

interpolation.

The provisions of this subsection shall not apply to any equipment completed and 

put into service before July 1, 1976 in the Palo Verde and Joshua Tree areas.

Before July 1, 1983, liquid sulfur compounds shall not be included as particulate

matter discharged from petroleum coke calciners.

(b) A person shall not discharge into the atmosphere from any source, particulate

matter in excess of 450 milligrams per cubic meter (0.196 grain per cubic foot) in 

discharged gas calculated as dry gas at standard conditions.

The provisions of this subsection shall apply only to any equipment completed and 

put into service before July 1, 1976 in the Palo Verde and Joshua Tree areas.

(c) The provisions of this rule shall not apply to emissions resulting from the

combustion of liquid or gaseous fuels in steam generators or gas turbines.

(d) For the purposes of this rule, emissions shall be averaged over one complete cycle 

of operation or one hour, whichever is the lesser time period.

(e) The provisions of this rule shall not apply to the use of equipment which complies 

with the emission limits specified in Rule 1112.1.
Rule 404 (Cont.) (Amended February 7, 1986)

404 - 2

TABLE 404(a)

Volume Discharged

Calculated as Dry Gas

At Standard Conditions

Maximum Concentration

of Particulate Matter”Allowed 

in Discharged Gas Calculated 

as Dry Gas at Standard

Conditions

Volume Discharged

Calculated as Dry Gas

At Standard Conditions

Maximum Concentration

of Particulate Matter

Allowed in Discharged

Gas Calculated as Dry Gas at

Standard Conditions

Cubic meters

Per Minute

Cubic feet

Per Minute

Milligrams per

Cubic Meter

Grains per

Cubic Foot

Cubic meters

Per Minute

Cubic feet

Per Minute

Milligrams per

Cubic Meter

Grains per

Cubic Foot

25 or

less

883 or

less

450 0.196 900 31780 118 0.0515

30 1059 420 .183 1000 35310 113 .0493

35 1236 397 .173 1100 38850 109 .0476

40 1413 377 .165 1200 42380 106 .0463

45 1589 361 .158 1300 45910 102 .0445

50 1766 347 .152 1400 49440 100 .0437

60 2119 324 .141 1500 52970 97 .0424

70 2472 306 .134 1750 61800 92 .0402

80 2825 291 .127 2000 70630 87 .0380

90 3178 279 .122 2250 79460 83 .0362

100 3531 267 .117 2500 88290 80 .0349

125 4414 246 .107 3000 105900 75 .0327

150 5297 230 .100 4000 141300 67 .0293

175 6180 217 .0947 5000 176600 62 .0271

200 7063 206 .0900 6000 211900 58 .0253

250 8829 190 .0830 8000 282500 52 .0227

300 10590 177 .0773 10000 353100 48 .0210

350 12360 167 .0730 15000 529700 41 .0179

400 14130 159 .0694 20000 706300 37 .0162

450 15890 152 .0664 25000 882900 34 .0148

500 17660 146 .0637 30000 1059000 32 .0140

600 21190 137 .0598 40000 1413000 28 .0122

700 24720 129 .0563 50000 1766000 26 .0114

800 28250 123 .0537 70000

or more

2472000

or more

23 .0100
405 - 1

(Adopted May 7, 1976)(Amended February 7, 1986)

RULE 405. SOLID PARTICULATE MATTER - WEIGHT

(a) A person shall not discharge into the atmosphere from any source, solid particulate 

matter including lead and lead compounds in excess of the rate shown in Table 

405(a).

Where the process weight per hour is between figures listed in the table, the exact 

weight of permitted discharge shall be determined by linear interpolation.

The provisions of this subsection shall not apply to any equipment completed and 

put into service before July 1, 1976 in the Palo Verde and Joshua Tree areas.

(b) A person shall not discharge into the atmosphere in any one hour from any source, 

solid particulate matter including lead and lead compounds in excess of 0.23

kilogram (0.5 pound) per 907 kilograms (2000 pounds) of process weight.

For the purposes of this subsection only, process air shall be considered to be a

material introduced into the process when calculating process weight.

The provisions of this subsection shall apply only to equipment completed and put 

into service before July 1, 1976 in the Palo Verde and Joshua Tree areas.

(c) For the purposes of this rule, emissions shall be averaged over one complete cycle 

of operation or one hour, whichever is the lesser time period.

(d) The provisions of this rule shall not apply to the use of equipment which complies 

with the emission limits specified in Rule 1112.1.
Rule 405 (Cont.) (Amended February 7, 1986)

405 - 2

TABLE 405(a)

Process Weight

Per Hour

Maximum Discharge Rate

Allowed for Solid Particulate Matter (Aggregate Discharged From All Points of

Process

Process Weight

Per Hour

Maximum Discharge Rate

Allowed for Solid Particulate Matter (Aggregate Discharged From All points of 

Process

Kilograms

Per Hour

Pounds

Per Hour

Kilograms

Per Hour

Pounds

Per Hour

Kilograms

Per Hour

Pounds

Per Hour

Kilograms

Per Hour

Pounds

Per Hour

100 or

less

220 or

less

0.450 0.99 9000 19840 5.308 11.7

150 331 0.585 1.29 10000 22050 5.440 12.0

200 441 0.703 1.55 12500 27560 5.732 12.6

250 551 0.804 1.77 15000 33070 5.982 13.2

300 661 0.897 1.98 17500 38580 6.202 13.7

350 772 0.983 2.17 20000 44090 6.399 14.1

400 882 1.063 2.34 25000 55120 6.743 14.9

450 992 1.138 2.51 30000 66140 7.037 15.5

500 1102 1.209 2.67 35000 77160 7.296 16.1

600 1323 1.340 2.95 40000 88180 7.527 16.6

700 1543 1.461 3.22 45000 99210 7.738 17.1

800 1764 1.573 3.47 50000 110200 7.931 17.5

900 1984 1.678 3.70 60000 132300 8.277 18.2

1000 2205 1.777 3.92 70000 154300 8.582 18.9

1250 2756 2.003 4.42 80000 176400 8.854 19.5

1500 3307 2.206 4.86 90000 198400 9.102 20.1

1750 3858 2.392 5.27 100000 220500 9.329 20.6

2000 4409 2.563 5.65 125000 275600 9.830 21.7

2250 4960 2.723 6.00 150000 330700 10.26 22.6

2500 5512 2.874 6.34 175000 385800 10.64 23.5

2750 6063 3.016 6.65 200000 440900 10.97 24.2

3000 6614 3.151 6.95 225000 496000 11.28 24.9

3250 7165 3.280 7.23 250000 551200 11.56 25.5

3600 7716 3.404 7.50 275000 606300 11.82 26.1

4000 8818 3.637 8.02 300000 661400 12.07 26.6

4500 9921 3.855 8.50 325000 716500 12.30 27.1

5000 11020 4.059 8.95 350000 771600 12.51 27.6

6000 13230 4.434 9.78 400000 881800 12.91 28.5

7000 15430 4.775 10.5 450000 992100 13.27 29.3

8000 17640 5.089 11.2 500000

or more

1102000

or more

13.60 30.0
407 - 1

(Adopted May 7, 1976)(Amended April 2, 1982)

RULE 407. LIQUID AND GASEOUS AIR CONTAMINANTS

(a) A person shall not discharge into the atmosphere from any equipment:

(1) Carbon monoxide (CO) exceeding 2,000 ppm by volume measured on a

dry basis, averaged over 15 consecutive minutes.

(2) Sulfur compounds which would exist as liquid or gas at standard

conditions, calculated as sulfur dioxide (SO2) and averaged over 15

consecutive minutes, exceeding:

(A) In the South Coast Air Basin, 500 ppm by volume, effective July 1, 

1982.

(B) In the Southeast Desert Air Basin portion of Riverside County:

(i) 500 ppm by volume for equipment which is issued a permit 

to construct or permit to operate after July 1, 1982.

(ii) 1,500 ppm by volume until January 1, 1984, and 500 ppm 

by volume thereafter for equipment that has been issued a

permit to construct or permit to operate prior to July 1,

1982.

(b) The provisions of this rule shall not apply to emissions from:

(1) Stationary internal combustion engines.

(2) Propulsion of mobile equipment.

(3) Emergency venting due to equipment failure or process upset.

(c) The provisions of subsection (a)(2) of this rule shall not apply to:

(1) Equipment which is subject to the emission limits and requirements of

source specific rules in Regulation XI.

(2) Equipment which complies with the gaseous fuel sulfur content

limits of Rule 431.1. 
SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT 

METHOD 100.1 

INSTRUMENTAL ANALYZER PROCEDURES FOR CONTINUOUS GASEOUS 

 EMISSION SAMPLING 

OFFICE OF OPERATIONS 

TECHNICAL SERVICES DIVISION 

MARCH 1989
METHOD 100.1 

INSTRUMENTAL ANALYZER PROCEDURES FOR CONTINUOUS GASEOUS 

 EMISSION SAMPLING 

TABLE OF CONTENTS 

1. Overview

1.1 Principle 

1.2 Applicability 

1.3 Range and Sensitivity 

2. Field Procedures

2.1 Definitions 

2.2 Measurement System Performance Specifications 

2.3 Apparatus and Measurement System 

2.4 Calibration Gases 

2.5 Measurement System Performance Test Procedures 

2.6 Emission Test Procedure 

2.7 Emission Calculation 

3. Calculations and Reporting 

3.1 Emission Rate of Gas 

3.2 Percent Excess Air 

3.3 Pollutant Concentration Calculated to 12 Percent 

 CO2, 3 Percent O2 and 15 Percent O2
METHOD 100.1 

INSTRUMENTAL ANALYZER PROCEDURES FOR CONTINUOUS GASEOUS 

EMISSION SAMPLING 

Section 1 of 3 

1. Overview

1.1 Principle 

A representative sample of an exhaust gas stream 

is continuously extracted, conditioned, and 

conveyed to instrumental analyzers for the 

determination of: 

• Sulfur dioxide (SO2) gas concentrations using 

an ultraviolet (UV) or a non-dispersive 

ultraviolet (NDUV) analyzer. 

• Oxides of nitrogen (NOx) gas concentrations 

using a chemiluminescent analyzer. 

 • Oxygen (O2) gas concentrations using an 

electrochemical (fuel cell) type analyzer. 

100.1-1
• Carbon monoxide (CO) gas concentrations using 

a non-dispersive infrared (NDIR) analyzer. 

• Carbon dioxide (CO2) gas concentrations using 

a non-dispersive infrared (NDIR) analyzer. 

Other systems may be used to measure SO2, NOx, 

O2, CO, and CO2 if they meet the specifications 

of this method and have been subjected to a 

relative accuracy test to determine equivalence. 

Performance specifications and test procedures 

are provided to ensure reliable data. Typical 

analyzer specifications are shown in Table 

100.1-1. 

1.2 Applicability 

This method measures emissions of SO2, NOx, O2, 

CO, and CO2 from stationary source gas streams 

flowing in ducts, stacks, and flues. This 

procedure does not supersede the New Source 

Performance Standards (NSPS) requirement for 

permanently installed continuous monitoring 

instruments. 

100.1-2
This test procedure is an alternative to SCAQMD 

reference methods, in particular SCAQMD Methods 

3.1, 6.1, 7.1, and 10.1. It should be used only 

on sources where its equivalency to the 

reference methods has been established, or where 

specific regulations for the source specify this 

procedure. 

1.3 Range and Sensitivity 

1.3.1 Analytical Range 

The analytical range is selected so that 

the sample gas concentration for each run 

is between 20 and 95 percent of the range, 

for 95 percent of the test period. The 

run is considered invalid if the measured 

gas concentration exceeds the range during 

the test period. Data obtained below 20 

percent of the range can be used only for 

qualitative purpose. 

1.3.2 Sensitivity 

The minimum detectable limit depends on 

the analytical range, span, and signal-to100.1-3
noise ratio of the measurement system. 

For a well designed system, the minimum 

detectable limit shall be less than 2 

percent of the range. 

100.1-4
METHOD 100.1 

INSTRUMENTAL ANALYZER PROCEDURES FOR CONTINUOUS GASEOUS 

EMISSION SAMPLING 

Section 2 of 3 

2. Field Procedures

2.1 Definitions 

2.1.1 Measurement System 

Equipment required to determine sample gas 

concentration consists of three major subsystems: 

 Sample Interface - The portion of the 

system used for sample acquisition, sample 

transport, sample conditioning, and 

protection of the analyzers from the 

effects of the stack effluent. 

 Gas Analyzer - The portion of the system 

that identifies the gas component and 

generates an output proportional to its 

concentration. 

100.1-5
 Data Acquisition - A strip chart recorder, 

analog computer and printer, or any 

combination thereof, for recording 

measurement data from the analyzer output. 

2.1.2 Range 

The upper limit of the gas concentration 

measurement range displayed on the data 

recorder. 

2.1.3 Calibration Gas 

A gas of known concentration in an inert 

diluent gas. 

2.1.4 Analyzer Calibration Error 

The difference between the known 

concentration of the calibration gas and 

the gas concentration exhibited by the gas 

analyzer when the calibration gas is 

introduced directly to the analyzer. 

100.1-6
2.1.5 Sampling System Bias 

The difference between the gas 

concentrations exhibited by the 

measurement system when calibration gas is 

introduced at the sampling probe tip 

filter and when the same calibration gas 

is introduced directly to the analyzer. 

2.1.6 Zero Drift 

The difference in the measurement system 

responses at a zero concentration level 

during the initial calibration, and final 

calibration check after a test. During 

this test there should be no unscheduled 

maintenance, repair, or adjustment of the 

measurement system. 

2.1.7 Calibration Drift 

The difference in the measurement system 

responses at a mid-range concentration 

level during the initial calibration, and 

final calibration check after a test. 

During this test there should be no 

100.1-7
unscheduled maintenance, repair, or 

adjustment of the measurement system. 

2.1.8 Response Time 

The time required for the system to 

display 95 percent of a step change in gas 

concentration on the data recorder. 

2.1.9 Interference Response 

The output response of the measurement 

system to a component in the sample gas, 

other than the gas component being 

measured. 

2.1.10 Calibration Curve 

A graph or other systematic method of 

establishing the relationship between the 

analyzer response and the actual 

calibration gas concentration introduced 

to the analyzer. 

100.1-8
 2.1.11 Linearity 

Maximum deviation as a percent of range, 

between a mid-range calibration reading 

and the reading predicted by a straight 

line drawn between high-range and zero gas 

calibration points. 

2.2 Measurement System Performance Specifications 

2.2.1 Analyzer Calibration Error 

 Less than + 2 percent of the reading for 

calibration gases. 

2.2.2 Sampling System Bias 

 Less than + 5 percent of the range for the 

zero, and mid-or high range calibration 

gases. 

2.2.3 Zero Drift 

 Less than + 3 percent of the range over 

the period of each run. 

100.1-9
2.2.4 Calibration Drift 

 Less than + 3 percent of the range over 

the period of each run. 

2.2.5 Interference Response 

Each of the analyzers described shall have 

the following minimum interference 

response to the gases listed. For 

example, an SO2 analyzer should respond no 

more than 30 ppm when the NO2

concentration in the sample gas is 2000 

ppm. 

 SO2 Analyzer 

 NO2 2,000/30 

 NH3 106/0 

 CO2 Analyzer 

 H2O 10,000/1 

CO 15,000/1 

 CH4 20,000/1 

CO Analyzer 

 H20 200,000/1 

 CO2 500,000/1 

 SO2 106/1 

 NO 106/1 

100.1-10
 NO2 106/1 

 HC 106/1 

 N20 103/1 

 2.2.6 Linearity 

 Less than + 1.0 percent of the range for 

the pretest and post test values. 

2.3 Apparatus and Measurement System 

A schematic of an acceptable measurement system 

is shown in Figures 100.1-1, 100.1-2, and 

100.1-3. The essential components of the 

measurement system are described below. 

2.3.1 Probe 

Use quartz, borosilicate glass, stainless 

steel, aluminum oxide, porcelain, 

Hastalloy, or Inconel tubing of 

approximately 1/4 inch diameter or larger. 

If stack temperatures are above 1200oF the 

probe should be designed to minimize the 

time the sample is kept at those high 

temperatures. Use a heated probe if 

condensation occurs. 

100.1-11
2.3.2 Sample Line 

Use Teflon or stainless steel tubing to 

transport the sample gas to the moisture 

removal system. The sampling line should 

be heated to prevent condensation. If the 

sample passes through a moisture knockout 

trap immediately after extraction from the 

stack, it is not necessary to heat the 

sample transport line downstream of the 

moisture removal trap. A sample line made 

from another material may be used if the 

material does not absorb, adsorb, evolve, 

or alter the pollutants being monitored. 

2.3.3 Probe Calibration System 

Calibration gases should be introduced 

into a baffled sample chamber around the 

probe tip filter when in the probe 

calibration mode. 

100.1-12
2.3.4 Sample Conditioning 

a. The sample conditioner should be 

capable of reducing moisture content 

to below a dewpoint of 35oF. 

b. All parts exposed to the sample should 

be glass, stainless steel, or Teflon. 

c. Remove water by using refrigeration or 

a permeation dryer designed to 

minimize contact between the 

condensate and sample gas. 

d. Provide for back flushing the probe 

filter with zero air to remove 

particulate buildup on the probe 

filter. 

2.3.5 Sample Transport Lines 

Use Teflon or stainless steel lines to 

transport the sample from the moisture 

removal system to the sample pump, sample 

flow rate control, and sample gas 

manifold. 

100.1-13
2.3.6 Particulate Filter 

Use an in-stack 5 micron stainless steel 

or Inconel 600 porous filter or a heated 

(sufficient to prevent water condensation) 

out-of-stack filter. The out-of-stack 

filter should be borosilicate or quartz 

glass wool or glass fiber mat. Additional 

filters at the inlet or outlet of the 

moisture removal system and inlet of the 

analyzer may be used to prevent 

accumulation of particulate material in 

the measurement system, and to extend the 

useful life of the components. All 

filters should be fabricated of materials 

that are nonreactive to the gas being 

sampled. 

2.3.7 Sample Pump 

Use a leak-free pump to pull the sample 

gas through the system at a flow rate 

sufficient to minimize the response time 

of the measurement system. The pump may 

be constructed of any material that is 

nonreactive to the gas being sampled. 

100.1-14
2.3.8 Sample Flow Rate Control 

Use a control valve and rotameter to 

maintain a sampling rate constant within 

10 percent. 

The tester may elect to install a back 

pressure regulator to maintain the sample 

gas manifold at a constant pressure in 

order to protect the analyzers from over 

pressurization or the need for flow rate 

adjustments. 

2.3.9 Sample Gas Manifold 

Use a sample gas manifold to divert a 

portion of the sample gas stream to the 

analyzer, and the remainder to the bypass 

discharge vent. The sample gas manifold 

also should include provisions for 

introducing calibration gases directly 

into the analyzer. The manifold may be 

constructed of any material that is 

nonreactive to the gas being sampled. 

100.1-15
2.3.10 Gas Analyzer 

Use a gas analyzer to continuously 

determine the SO2, NOx, 02, CO2, or CO 

concentration in the sample gas stream. 

Each analyzer should meet the applicable 

performance specifications of Section 2.2. 

Each analyzer should be provided with a 

means of controlling its flow rate and a 

device for determining proper sample flow 

rate (e.g. precision rotameter, pressure 

gauge downstream of all flow controls). 

 An NO2 to NO converter in an NOx analyzer 

is the portion of the system that converts 

nitrogen dioxide (NO2) in the sample gas 

to nitric oxide (NO). An NO2 to NO 

converter is not necessary if data are 

presented to demonstrate that the NO2

portion of the exhaust gas is less than 5 

percent of the total NOx concentration. A 

high temperature (650oC) stainless steel 

converter should be used when no NH3 is 

present and a low temperature (350oC) 

molybdenum converter should be used when 

NH3 is present. Other converters may be 

used if equivalence is demonstrated. 

100.1-16
 Housing the analyzer in a clean, 

thermally-stable, vibration-free 

environment will minimize drift in the 

analyzer calibration. 

2.3.11 Data Recorder 

Use a strip chart recorder, analog 

computer, or digital recorder, for 

recording measurement data. The data 

recorder resolution, or readability should 

be 0.5 percent of range. Sampling 

measurements should be obtained at a 

minimum of 1 minute intervals. 

2.3.12 Interference Response Sampling System 

Introduce an interference test gas to the 

analyzer. The analyzer zero should be 

given a positive offset prior to the test 

to allow measurement of a negative 

interference. As an alternative, offset 

chart paper may be used to avoid changing 

the analyzer zero. 

100.1-17
 2.3.13 Pitot Tubes 

Same as required by SCAQMD Methods 1.1 and 

2.1. 

2.3.14 Differential Pressure Gauge 

Same as required by SCAQMD Methods 1.1 and 

2.1. 

2.3.15 Sample Gas Moisture Content Equipment 

As specified by SCAQMD Method 4.1. 

 2.3.16 Barometer 

Use a mercury, aneroid, or other barometer 

capable of measuring atmospheric pressure 

to within 0.1 in. Hg. 

2.3.17 Vacuum Gauge 

Use a 30 in. Hg gauge for leak checking 

the sampling system. 

100.1-18
 2.3.18 Thermocouple 

Use a Type K thermocouple to measure the 

temperature of the stack gas. 

2.4 Calibration Gases 

 

 Calibration gases shall be certified according to 

EPA Traceability Protocol Number 1 (see Table 

100.1-2 for cylinder gas recertification 

schedule) or certified to an analytical accuracy 

of + 1 percent and be traceable to applicable 

NIST* Standard Reference Materials (SRM's). 

Traceability shall include identification of 

applicable SRM and its cylinder number. 

 Super blends, i.e. gas mixtures of nitric oxide, 

sulfur dioxide, carbon monoxide and carbon 

dioxide with nitrogen as the balance gas, may be 

used for simultaneous calibration of multiple 

analyzers. The average deviation of each 

component gas shall not exceed + 1 percent of the 

tag value, and shall be confirmed using NIST 

traceable standards within the certification 

period of the lowest component in the mixture. 

 

100.1-19
EPA Traceability Protocol No. 1 is in the 

 Appendix. 

 

*NIST - National Institute of Standards and 

 Technology 

Use three calibration gases as specified below: 

2.4.1 High-Range Gas 

The concentration should be equivalent to 

80 to 100 percent of the range. 

2.4.2 Mid-Range Gas 

The concentration should be equivalent to 

40 to 60 percent of the range. 

2.4.3 Zero Gas 

The impurity concentration should be less 

than 0.25 of one percent of the range. 

Purified ambient air may be used for the 

zero gas by passing compressed air through 

a heatless dryer, a catalytic oxidizer, 

and a carbon dioxide scrubber. 

100.1-20
Use ultra zero grade nitrogen gas for 

zeroing the 02 analyzer. 

2.5 Measurement System Performance Test Procedures 

Perform the following procedures before 

measurement of emissions (Section 2.6). 

2.5.1 Cleaning of Sample Train 

As needed, thoroughly flush the probe, 

heat-trace line, and sample conditioner 

with distilled water, followed by acetone. 

Dry with filtered dry air. 

2.5.2 Continuous Analyzers 

Allow analyzers to warm up according to 

manufacturer's instructions. 

2.5.3 Sampling System Preparation 

A leak check of the sampling system is a 

good practice. However, it is optional. 

Assemble the sample train as shown in 

Figures 100.1-1, 100.1-2 and 100.1-3. 

100.1-21
Leak check the vacuum side of the assembly 

to a minimum of 20 inches of Hg (gauge). 

The sampling system should hold 20 inches 

of Hg vacuum for 5 minutes with less than 

1 in. Hg loss. Correct any leaks found 

and repeat the leak check until a 

satisfactory result is obtained. Check 

the pressure side of the system with 

liquid soap solution and correct any 

leaks. Alternative leak check methods are 

acceptable if equivalent or better than 

the specified method. 

The sample train assembly may be modified 

as follows to reflect actual stack 

conditions: 

• If the stack is at or below ambient 

temperature and condensation is not 

observed upstream of the sample 

conditioner, the probe heating element 

and the heat trace line can be 

eliminated. 

• If only concentration measurements are 

required, the Pitot tube can be 

eliminated. 

100.1-22
Introduce zero and high range calibration 

gases directly to the instruments and make 

all necessary adjustments to calibrate the 

analyzer and the data recorder. Adjust 

system components to achieve individual 

analyzer sampling rates recommended by the 

instrument manufacturer. 

2.5.4 Analyzer Calibration Error 

Conduct the analyzer calibration error 

check at the beginning and end of each 

test run by introducing calibration gases 

to the measurement system at any point 

upstream of the gas analyzer as follows: 

a. After the measurement system has been 

prepared for use, introduce the zero, 

mid-range, and high-range gases to the 

analyzer. During this check, make no 

adjustments to the system except those 

necessary to achieve the correct 

calibration gas flow rate at the 

analyzer. Record the analyzer 

responses to each calibration gas on 

a form similar to Figure 100.1-4. 

100.1-23
The calibration error check should be 

considered invalid if the gas 

concentration displayed by the 

analyzer exceeds + 2 percent of the 

reading for any of the calibration 

gases. If an invalid calibration is 

exhibited, take corrective action and 

repeat the analyzer calibration error 

check until acceptable performance is 

achieved. 

2.5.5 Instrument Response Time 

Establish during semi-annual 

 certification. 

2.5.6 Sampling System Bias Check 

A bias check of the sampling system is 

 mandatory. 

Backflush gas through the probe as 

necessary to prevent particulate buildup 

on the probe filter. Perform the sampling 

system bias check by introducing 

calibration gases into a baffled sample 

chamber around the probe tip filter. 

100.1-24
A zero gas and either the mid-range or 

high-range gas, whichever most closely 

approximates the effluent concentrations, 

should be used for this check as follows: 

a. Introduce the upscale calibration gas 

and record the gas concentration 

displayed by the analyzer on a form 

similar to Figure 100.1-5. Introduce 

the zero gas and record the gas 

concentration displayed by the 

analyzer. During the sampling system 

bias check operate the system at the 

normal sampling rate and make no 

adjustments to the measurement system 

other than those necessary to achieve 

manufacturer recommended calibration 

gas flow rates at the analyzer. 

b. The sampling system bias check shall 

be considered invalid if the 

difference between the gas 

concentrations exhibited by the 

measurement system when a known 

concentration gas is introduced at the 

sampling probe tip and when the same 

gas is introduced directly to the 

100.1-25
analyzer, exceeds + 5 percent of the 

analyzer range. If an invalid 

calibration is exhibited, take 

corrective action and repeat the 

sampling system bias check until 

acceptable performance is achieved. 

If adjustment to the analyzer is 

required, first repeat the analyzer 

calibration error check, then repeat 

the sampling system bias check. 

2.5.7 NO2 to NO Conversion Efficiency 

Conduct an NO2 to NO conversion efficiency 

test in accordance with EPA Method 20 or 

by using an NBS traceable gas mixture of 

NO2 in air. 

2.6 Emission Test Procedure 

Traverse the duct to determine if there is 

stratification (see Chapter X). Single point gas 

sampling is acceptable if the gas composition is 

homogeneous, i.e. < 10 percent variation between 

any two traverse points in the gas stream 

throughout the cross sectional diameter of the 

100.1-26
stack. For multipoint gas sampling use every 

other point, as required by SCAQMD Method 5.1 for 

particulate matter. Determine moisture content 

and velocity pressures in the stack gas according 

to SCAQMD Methods 1.1, 2.1 and 4.1 if required 

for mass flow rate calculations. The probe inlet 

should never be closer than one inch to the stack 

wall. As an alternate method, the mass flow rate 

may be obtained by stoichiometric and gas 

composition relations. 

2.6.1 Chart Recorder Label 

Turn on strip chart recorder and label the 

chart as to pollutant, source, range, 

calibration cylinder ID number, certified 

expiration date, zero and upper range 

calibration settings, chart speeds, date, 

time, person operating instruments, and 

other pertinent data. 

2.6.2 Sample Probe Traverse and Minimum Sampling 

Time 

Insert the sample probe assembly into the 

stack and blank off the remainder of the 

opening. Conduct a gas sample traverse to 

100.1-27
determine if single point sampling is 

acceptable and label the response obtained 

on the strip chart. If a traverse is 

required, leave the probe at each traverse 

point for at least the system response 

time plus one minute, allowing enough time 

for the system to be flushed and the 

instruments to respond fully. Move the 

probe to the next traverse point and 

repeat. Continue until the stack has been 

fully traversed. 

A minimum sample time of 60 minutes is 

recommended. See District Rules and 

Regulations and permit conditions for 

applicable requirements. When the test 

duration exceeds one hour, conduct zero 

and span checks every 2 hours. Adjust 

settings as necessary, mark strip charts, 

and record in log books. 

2.6.3 Zero and Calibration Drift Tests 

Immediately preceding and following each 

run, or if adjustments are necessary for 

the measurement system during the run, 

repeat the sampling system bias check 

100.1-28
procedure. (Make no adjustments to the 

measurement system until after the drift 

checks are completed.) Record the 

analyzer's responses on a form similar to 

Figure 100.1-5. 

2.6.3.1 If either the zero or upscale 

calibration value exceeds the 

sampling system bias 

specification, then the run is 

considered invalid. Repeat both 

the analyzer calibration error 

check procedure and the sampling 

system bias check procedure 

before repeating the run. 

2.6.3.2 If both the zero and upscale 

calibration values are within the 

sampling system bias 

specification, then use the 

average of the initial and final 

bias check values to calculate 

the gas concentration for the 

run. If the zero or upscale 

calibration drift value exceeds 

the drift limits, based on the 

difference between the sampling 

100.1-29
system bias check responses 

immediately before and after the 

run, repeat both the analyzer 

calibration error check procedure 

and the sampling system bias 

check procedure before conducting 

additional runs. 

2.6.4 Post Run Leak Check 

 

If a prerun leak check is conducted, 

proceed as follows: 

See Section 2.5.3. If the leak rate is 2 

percent or more of the total sample flow 

rate (approximately 0.4 SCFH) discard the 

test. 

2.7 Emission Calculation 

Determine the average gas effluent concentration 

from the average gas concentration displayed by 

the gas analyzer and adjust for zero and high 

range calibration drift. The average gas 

concentration displayed by the analyzer may be 

determined by integration of the area under the 

curve for chart recorders, or by averaging all of 

100.1-30
the effluent measurements. Alternatively, the 

average may be calculated from measurements 

recorded at equally spaced intervals over the 

entire duration of the run. Sampling 

measurements should be obtained at a minimum of 1 

minute intervals. Calculate the effluent gas 

concentration using the following equation: 

 - Cma Cgas = (C - Co) 

 Cm - Co

 where: 

 Cgas = Effluent gas concentration, dry basis, 

 ppm 

 - 

C = Average gas concentration indicated by 

gas analyzer, dry basis, ppm 

 Cma = Actual concentration of the upscale 

calibration gas, ppm 

 Cm = Average of initial and final system 

calibration bias check responses for the 

upscale calibration gas, ppm 

100.1-31
 Co = Average of initial and final system 

calibration bias check responses for the 

zero gas, ppm 

100.1-32
METHOD 100.1 

INSTRUMENTAL ANALYZER PROCEDURES FOR CONTINUOUS GASEOUS 

EMISSION SAMPLING 

Section 3 of 3 

3. Calculations and Reporting 

3.1 Emission Rate of Gas 

 (Cg)(M) 

 E = (Q) (60) 

 379 x 106

 

 where:

E = Emission rate, lb/hr 

 Cg = Concentration of gas, ppm 

M = Molecular weight of gas*, lb/lb- 

 mole 

Q = Stack Effluent, dscfm 

60 = Conversion factor, min/hr 

379 x 106 = Conversion factor, scf/lb-mole 

 *NOx is often expressed as NO2

100.1-33
3.2 Percent Excess Air 

 [O2 - 0.5 CO] 

EA = x 100 

 [0.264 N2 - (O2 - 0.5 CO)] 

 where: 

 

EA = Percent excess air 

 O2 = Percent O2 by volume, dry basis 

 (measured) 

CO = Percent CO by volume, dry basis 

 (measured) 

 N2 = Percent N2 by volume, dry basis 

 (calculated) 

0.264 = Ratio of O2 in air, v/v 

 

3.3 Pollutant Concentration Calculated to 12 Percent 

 CO2, 3 Percent O2, and 15 Percent O2

 

 Concentration(12 Percent O2) = 

 12 Concentration(std) x 

 CO2 (measured) 

 CO2 = Percent CO2 by volume, dry basis 

 Concentration(3 Percent O2) = Concentration(std)

 20.9 - 3.0 Concentration(std) x 

 20.9 - O2 (measured) 

100.1-34
 Concentration(15 Percent O2) = Concentration(std) 

 20.9 - 15.0 

 Concentration(std) x 

 20.9 - O2 (measured) 

Based on O2 in air as 20.9 percent.

100.1-35
100.1-36 

TABLE 100.1-1 

ANALYZER SPECIFICATIONS FOR CONTINUOUS GASEOUS EMISSION STACK SAMPLING 

Sulfur 

Dioxide 

Oxides of 

Nitrogen 

Carbon 

Monoxide 

Carbon 

Dioxide Oxygen 

Typical 

Principle of 

Operation 

(1) 

Typical 

Range of 

Conc. 

Noise Level, 

Percent of 

Full Scale 

Response 

Time, Time 

Interval 

from a Step 

Change in 

Input Conc. 

at Inlet to 

Instrument 

to Output 

Reading of 

95 Percent 

of Steady 

State 

Analyzer 

Calibration 

Error, 

Percent of 

Range for 

the Zero, 

Mid-Range 

Calibration 

Gases 

Zero Drift, 

Percent of 

Range Over 

the Period 

of Each Run 

Ultra-Violet 

or NonDispersive 

Ultra-Violet 

Absorption 

Photometry 

50, 250, 

1000 ppm 

< ± 1.0 

10 Seconds 

< ± 2.0 

< ± 3.0 

Chemiluminescence 

10, 25, 100, 250, 

1000, 10,000 ppm 

< ± 1.0 

3 Seconds 

< ± 2.0 

< ± 3.0 

NonDispersive 

Infrared 

Absorption 

5, 10, 50, 

500, 2500, 

5000 ppm 

< ± 1.0 

10 Seconds 

< ± 2.0 

< ± 3.0 

NonDispersive 

Infrared 

Absorption 

2, 10, 20 

Percent 

< ± 1.0 

10 Seconds 

< ± 2.0 

< ± 3.0 

Electrochemical

5, 10, 25 

Percent 

< ± 1.0 

10 Seconds 

< ± 2.0 

< ± 3.0 
100.1-37 

TABLE 100.1-1 CONT. 

Sulfur 

Dioxide 

Oxides of 

Nitrogen 

Carbon 

Monoxide 

Carbon 

Dioxide Oxygen 

Calibration 

or Span 

Drift, 

Percent of 

Range Over 

the Period 

of Each Run 

Precision, 

Maximum Avg. 

Deviation 

from Mean 

Change as 

Percent of 

Range 

Linearity 

(2) 

Interference 

Response 

< ± 3.0 

< ± 1.0 

< ± 1.0 

NO2 2000/30 

NH3 106/0 

< ± 3.0 

< ± 1.0 

< ± 1.0 

- 

< ± 3.0 

< ± 1.0 

< ± 1.0 

H20 200,000/1 

CO2 500,000/1 

SO2 106/1 

NO 106/1 

NO2 106/1 

HC 106/1 

N2O 103/1 

< ± 3.0 

< ± 1.0 

< ± 1.0 

H2O 10,000/1 

CO 15,000/1 

CH4 20,000/1 

< ± 3.0 

< ± 1.0 

< ± 1.0 

- 

(1 Other types may also be acceptable. 

(2) Maximum deviation between a mid-range calibration reading and the reading predicted by 

a straight line drawn between high-range and zero gas calibration points, as a percent 

of range. 
TABLE 100.1-2 

Cylinder Gas Recertification Schedule for EPA 

Protocol 1 Traceable Standards

Pollutant Balance Gas Concentration 

Range 

Maximum 

Months Until 

Recertificati

on for 

Passivated 

Aluminum 

Cylinders:

Al 

Carbon Monoxide 

Carbon Dioxide 

Nitric Oxide 

Nitrogen Dioxide 

Oxygen 

Propane 

Sulfur Dioxide 

Others not 

Specifically 

Listed 

N2 Air 

N2

N2

N2 or Air 

N 2

Air 

N2 or Air 

≥ 10 ppm 

> 0.5% 

≥ 5 ppm 

≥ 1000 ppm 

≥ 2% 

≥ 3 ppm 

50-499 ppm 

36 

36 

24 

24 

36 

36 

24 

 6 

100.1 - 38
100.1 - 39
100.1 - 40
100.1 - 41
100.1-42

Date

Analyzer

Range

Cylinder 

Value 

(Indicate 

Units)

Analyzer 

Calibration 

Response 

(Indicate 

Units)

Absolute 

Difference 

(Indicate 

Units)

Difference 

(Percent 

of Range)

Zero Gas

Mid-Range 

Gas

High-range 

Gas

Pretest Linearity Error Percent Range

Post Test Linearity Error Percent Range

Figure 100.1-4

Analyzer Calibration Data Form
100.1 - 43
GENERAL CONTINUOUS GAS MONITORING REQUIREMENTS

(600perf_pro1.doc : REV 9/20/2005 2:41 PM) 

The District requires continuous gas monitoring equipment 

employing sample extraction and conditioning, and 

electronic detection, to be conducted strictly according to 

District Method 100.1, with the emphasis upon 

representativeness, documentation, and quality assurance. 

This includes, in part: 

1. Gas analyzers must meet minimum acceptable standards for 

method of detection, sensitivity, noise, precision, 

linearity, and interference (see TABLE 100.1-1 for 

details). Also, the gas sample extraction and 

conditioning equipment (probe, filter, pump, conditioner, 

connective plumbing, etc., and data acquisition and 

logging equipment shall meet minimum acceptable 

specifications, as described in Method 100.1. 

2. It is recommended that the entire sampling system for 

continuous gas monitoring instruments should be leak 

checked before and after each test run by evacuating 

the system to a minimum of 20 in. Hg vacuum, and 

plugging for a period of 5 minutes. The resultant 

loss of vacuum can not exceed 1 in. Hg during this 

period. 

3. Calibration of all analyzers must be accomplished at 

zero, mid span (40-60% of full scale range), and high 

span (80-95% of full scale range). The lowest 

practicable range should be selected for monitoring, 

so that the measured emission values are within 20-95% 

of the range. If a significant amount of the data are 

outside of this range, the data may be rejected, 

depending upon the application. 

4. The calibration gases must be certified according to 

EPA Protocol Number 1, or certified to an analytical 

accuracy of +1% and be NIST traceable (except cal gases 

used for system bias check), following EPA600/R93/224, “EPA Traceability Protocol for Assay and 

Certification of Gaseous Calibration Standards”, TABLE 

2-2. Superblend or multi-component blend gas 

recertifications are based upon the individual 

component(s) with the shortest recertification date. 

5. Field calibrations employing gas dilution systems 

(mass flow or critical orifice) must be performed in 

accordance with EPA Method 205, "Gas Dilution 

Verification Protocol", or available “Draft” SCAQMD 

Method, and supported with appropriate documentation. 

A 5-point check is required. 

6. A calibration error check, and zero/span drift check 

must be performed before and after each test run. 

100.1 - 44
Calibration error must be less than +2% of the range of 

measurement for zero, mid, and high range calibration 

gases. Zero/span drift must be less than +3% of the 

range of measurement. 

7. A system bias check must be performed before and after 

each test run by alternately introducing cal gases to 

the entire sampling system, then to the gas 

analyzer(s), for comparison. The difference can not 

exceed +5% of the analyzer range. 

8. Semi-annual analyzer certifications consisting of 

linearity plot, calibration curve, response time, and 

interference response must be furnished with the other 

calibrations to satisfy Q/A documentational 

requirements. 

9. NOX measurement must be performed in the NOX mode of 

the analyzer. An NO2 to NO converter is required if 

NO2 constitutes 5% or more of the total NOX in the 

sample stream, or the rule or permit condition 

requires "NOX" monitoring. The NO2 to NO converter 

must be at least 90% efficient (use the NO2 to NO 

converter efficiency procedure). The converter should 

be high temperature (650oC) stainless steel, if no NH3

is present. If NH3 is present in the sample stream, 

then a low temperature (350oC) molybdenum catalyst must 

be used in the converter. This check must be done at 

the beginning of the test. 

10.The connective tubing from the probe to the sample 

conditioner must be heated above the dewpoint and the 

dewpoint reported. The sample conditioner must be 

able to maintain a dewpoint temperature of 37oF or 

less. (Refer to the “Sample Conditioning Requirements 

for Method 100.1” Addendum, for details) 

11.Data recorder resolution must be at least 0.5% of the 

range of measurement. A data point for each 

contaminant/diluent monitored must be recorded at 

least once/minute. Analog chart recorders must have a 

minimum 10-inch chart width, with 100 minor divisions. 

12.All facets of testing must be continuously recorded. 

This includes the 3-point calibration, system bias, 

calibration error, and zero/span drift checks, which 

must precede and conclude each test run. 

100.1 - 45
13.All chart traces, or digital printouts, must be 

included in the final report and must be clearly 

identified as to: 

• location/source • range changes • operator initials • range of measurement • date/running times • calibrations • actual test interval • calibration gas conc./ 

cylinder number • contaminant/diluent • range of calibration 

14.When more than one gas trace is shown on a chart, the 

individual traces must be distinguishable by color coding 

or some other means (original charts may be submitted, and 

returned following evaluation). If a gas measurement 

range has been "offset" from zero, or zero has been 

"transposed to the right side of the recorder chart, it 

must be clearly identified. this offset should not be 

more than 5-small divisions of the chart. This data must 

be corrected using the ratio of the offset. 

15.Gaseous measurements must be conducted a minimum of 15 

continuous minutes at each load or specified condition, 

after the readings have stabilized (RECLAIM reference 

method sampling requires a minimum of 30 continuous 

minutes at each load for RATAs). Processes having 

multiple exhausts exhibiting non-cyclic (i.e. steadystate) characteristics may alternatively be monitored 

using the above criteria. Otherwise, simultaneous 

sampling may be required. 

16.Sampling locations not meeting the minimum site selection 

standards for District Method 1 must be tested for 

absence of stratification. (A gaseous constituent 

concentration profile differing more than 10% between any 

two monitoring points within the same cross-sectional 

plane of a stack or duct indicates stratification.) If 

stratification is present, and alternate approved site 

selection or modification is not possible, then special 

monitoring (see Chapter X of the District Source Testing 

Manual) will be required. 

100.1 - 46
ATTACHMENT B

ADDENDUM TO "General Continuous Gas Monitoring Requirements"

SAMPLE CONDITIONING REQUIREMENTS FOR METHOD 100.1

For Method 100.1 tests, proper sample conditioning is 

essential for representative sampling. Sample conditioning 

includes removal of particulate matter and moisture present 

in the sample gas stream. The design of the sample 

conditioning system must be such that during the process of 

particulate and moisture removal, the pollutants of 

interest are not also removed from the gas stream. Method 

100.1 requires that the tester select a system which will 

have a minimum "scrubbing" effect. In particular, NO2 and 

SO2 are more susceptible to scrubbing than, for example NO 

or CO, because of their high solubility in water. Since 

Method 100.1 is a reference method, it is required that a 

sample conditioning system cause only minimum loss of these 

pollutants. 

The District recommends a gas sampling system which can be 

used universally1. (i.e. under all testing conditions). The 

set-up includes a heated 1/4-inch stainless steel probe 

with a 50-80 micron size, sintered 316 stainless steel or 

ceramic filter at the tip; and a short (not more than 6 

feet) heated Teflon line to the sample conditioning system. 

The temperature of the probe and the Teflon line should be 

maintained at about 250oF. The conditioning system consists 

of a pair of standard Greenburg-Smith impingers with the 

stems cut to about 1-inch length from the top, immersed in 

a bath containing water and dry ice pellets, and 

immediately followed by a thermo-electric cooler or 

permeation drier. The gas temperature at the outlet of the 

impinger shall be less than 60oF and the gas at the drier 

outlet shall be maintained at a dew point less than 37oF. 

If the drier can not be directly connected to the impinger 

outlet, then a Teflon line heated to 10o

F above the impinger 

outlet gas temperature can be used for connection. Another 

particulate filter (about 5 microns) should be in the line 

right after the cooler/drier. All the temperatures should 

be measured and recorded, preferably on a strip chart 

recorder. If the moisture content of the exhaust gas is 

below 5% and the sample gas flow rate is less than 10 

liters/minute, the impinger set-up need not be used, as 

long as no moisture condensation occurs in the system and 

the conditioned sample is maintained at the required dew 

point. 

PRECAUTIONS: Never allow the water in the impingers to 

accumulate more than 1/4 of the impinger height. Don't 

allow the water bath to become frozen around the impingers, 

or cracking of the glassware may result. Assure that the 

thermo-electric cooler/permeation drier has adequate design 

capacity. Follow a good maintenance schedule for the 

cooler/drier gas conditioning system. 

100.1 - 47
ATTACHMENT B

Other systems may be used, upon District approval, 

emphasizing the requirements that water is removed 

immediately after separation from the gas stream, and 

minimal water contact with the gas stream is assured. 

1. An example of a non-universally applicable water removal system is 

based on the refrigerated cooling coil principle. A refrigerated 

cooling coil system can scrub out a high percentage of water soluble 

pollutants due to a comparatively long residence time, and intimate 

contact between the sample gases and the water droplets collected on 

the inside of the coil. Consequently, it will show a high bias for 

the CEMS being tested if the sample gas contains a significant amount 

of NO2, compared to NOx or SO2, and therefore it may not be suitable 

in all cases. 

600perf_pro1.doc : REV 9/20/05

100.1 - 48
ATTACHMENT C

ADDENDUM TO "General Continuous Gas Monitoring Requirements"

NO2 TO NO CONVERSION TEST PROCEDURE 

(Alternative to O3 Titration Method-40 CFR 50.1, Appendix F) 

1. NOx Analyzer Requirements 

a. Full span range 0-20 ppm or 0-25 ppm 

b. Equipped with NO and NOx modes 

2. Auditing Gas Requirements 

a. NO2 in air (or N2): Use NO2 in air for a stainless steel 

converter. 

b. Concentration of NO2: 15 to 18 ppm (C0, ppm) 

c. Recertification: An audit gas should be recertified after 

six months. 

3. Calibration Gas Requirements 

a. Concentration: 

NO (17 to 19 ppm) with less than 0.1 ppm NO2 – High Span 

NO (10 to 13 ppm) with less than 0.1 ppm NO2 – Mid Span 

b. Zero Gas: High purity N2

4. Calibration of Analyzer: 

a. Calibrate NO mode with the NO calibration gases. 

b. Calibrate NOx mode with the same gases without any gain 

adjustment. 

b1. If the analyzer is equipped with two independent gain 

adjusting circuits, skip 4.b., then repeat 4.a. for the NOx

mode. 

5. Conversion Efficiency (CE) Test 

a. Analyze the audit gas with NO mode. Read and standardize 

concentration. (C1, ppm) 

b. Analyze the audit gas with NOx mode. Read and standardize 

concentration. (C2, ppm) 

6. Calculation for Conversion Efficiency: 

100 | | %

0

2 1 x

C

C C CE − = 

7. Criteria for Acceptability of CE 

a. %CE must be larger than 90%. 

b. C1 must be less than 5% of total NOx (NO + NO2) in the NO2

audit gas (Section 2b). 

NOTE: NO2 audit gas concentration of higher value than what is specified in

Section 2. may be required where NO2 present in the exhaust gas being measured

is greater than 30 ppm. Select the NO2 gas within 10% of the expected NO2

concentration in the exhaust. 

600perf_pro1.doc : REV 9/20/05 

100.1 - 49
Appendix 

The EPA Traceability Protocol can be downloaded here: 

http://www.epa.gov/oamcinc1/0410474/protocol.pdf

100.1 - 50
SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT 

METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

OFFICE OF OPERATIONS 

TECHNICAL SERVICES DIVISION 

OCTOBER 2005 
METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

TABLE OF CONTENTS 

Section

1. Overview

 1.1 Principle 

 1.2 Applicability 

2. Field Procedures

 2.1 Sampling Apparatus 

 2.2 Sampling Reagents 

 2.3 Pretest Determinations 

 2.4 Gas Volume Meter Checks 

 2.5 Pretest Preparation 

 2.6 Leak Check Procedures 

 2.7 Sampling Train Operation 

 2.8 Calculation of Percent Isokinetic 

 2.9 Sample Handling 

 2.10 Calibrations 
3. Laboratory Procedures

 3.1 Apparatus 

 3.2 Reagents 

 3.3 Pretest Preparation 

 3.4 Preparation of Sample Collection Train 

 3.5 Leak Check 

 3.6 Sample Recovery 

 3.7 Sample Analysis 

 3.8 Calculations and Reporting 

 3.9 Calibrations 

4. Engineering Calculations and Reporting

 4.1 Calculations 
METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

Section 1 of 4 

1. Overview

1.1 Principle 

 

A sample is withdrawn isokinetically from the 

source through a sample train by a metering 

system. Filterable particulate matter is 

collected on a glass fiber filter kept inside the 

stack. Condensibles and particulates passing 

through the filter are collected in impingers 

containing deionized water. The impingers are 

contained in an ice bath to maintain a sampled 

gas temperature of approximately 15oC (60oF). A 

separate train for sulfuric acid mist may be 

required (see below). 

The total particulate mass is defined as the sum 

of the mass collected in the probe, filter, and 

impingers after removal of uncombined water, the 

5.3 - 1 
organic extraction, and the sulfuric acid 

collected from the separate sulfuric acid train 

(if required). The solid particulate matter mass 

is defined as the total particulate matter mass 

minus extractable organic matter and sulfuric 

acid. 

An adjustment to the total particulate matter 

mass is allowed for sulfuric acid formed from 

reactions between SO2 and SO3 with the sample 

train components. When ammonia is injected to 

enhance the efficiency of a control device, a 

second adjustment is allowed for total sulfate. 

This adjustment is allowed for fluid catalytic 

cracking units only. 

Because of the complexity of this method testers 

must be trained and experienced in the test 

procedures. 

1.2 Applicability 

 

This method measures particulate emissions from 

stationary sources, except when determining 

compliance with New Source Performance Standards. 

It does not apply to stacks that contain liquid 

5.3 - 2 
droplets, or saturated with water vapor, or where 

the temperature is greater than 204oC (400oF). 

In addition, this method should not be used if 

the projected cross sectional area of the probe 

extension-filter holder assembly covers more than 

5 percent of the stack cross sectional area (see 

Figure 5.3-1). This method is recommended for 

testing cement plants and other sources emitting 

highly hygroscopic particulate matter. 

5.3 - 3 
METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

Section 2 of 4 

2. Field Procedures

2.1 Sampling Apparatus 

 2.1.1 Sampling Train 

 

A schematic of the sampling train used in 

this method is shown in Figure 5.3-2. The 

procedure for the preparation of the 

sample collection train is given in Method 

5.1, Section 3.2.1. The sampling train 

consists of the following components: 

 a. Probe Nozzle 

The nozzle material should be 316 

stainless steel or glass, with a 

sharp, tapered leading edge. The 

taper angle should be <30o and on the 

5.3 - 4 
outside, to preserve a constant 

internal diameter. The stainless 

steel nozzle should be constructed 

from seamless tubing. Other materials 

which will not be corroded by the 

sampled gases or interfere with sample 

recovery may be used. 

A range of nozzle sizes suitable for 

isokinetic sampling should be 

available in increments of 0.16 cm 

(1/16 in.), e.g. 0.32 to 1.27 cm (1/8 

to 1/2 in.) or larger if higher volume 

sampling trains are used. Each nozzle 

must be calibrated according to 

procedure outlined in Method 5.1, 

Section 2.1. 

b. Filter Holder 

Use a borosilicate glass filter 

holder, with a Teflon, Teflon-coated 

stainless steel, or stainless steel 

support and a silicone rubber gasket. 

Gasket made of other materials such as 

stainless steel, Teflon, or Viton may 

5.3 - 5 
be used if they do not react with the 

particulate matter or sampled gases. 

Fritted glass supports are 

unsatisfactory for post-filter 

analysis. The holder design provides 

a positive seal against leakage from 

the outside or around the filter. 

c. Probe Liner 

Whenever practical, use borosilicate 

or quartz glass probe liners. Metal 

liners such as 316 stainless, Inconel, 

Incoloy 825, or other corrosion 

resistant metals made of seamless 

tubing may be used when the 

concentration of acid particulate is 

less than 1 mg/m3 at probe conditions 

or SO2 is less than 20 ppm. 

d. Pitot Tube 

Use an S-type Pitot tube, as described 

in Section 1.1 of Method 2.1, or other 

device approved by the Executive 

Officer. Attach the Pitot tube to the 

5.3 - 6 
probe, as shown in Figure 5.3-2, to 

allow constant monitoring of the stack 

gas velocity. If this is not 

practical see Chapter X, section on 

Flue Factor. 

The impact (high pressure) opening 

plane of the Pitot tube must be even 

with or above the nozzle entry plane 

(see Method 2.1) during sampling. The 

S-type Pitot tube assembly must have a 

known coefficient, as determined in 

Method 2.1. 

e. Differential Pressure Gauge 

 

Use an inclined manometer or 

equivalent device, as described in 

Method 2.1, for stack velocity head 

readings, and a separate manometer for 

orifice differential pressure 

readings. 

f. Impinger Train 

5.3 - 7 
The train consists of four GreenburgSmith design impingers connected in 

series with leak-free ground glass 

fittings, or any similar leak-free 

non-contaminating fittings. The first 

and second impingers must be of the 

Greenburg-Smith design with the 

standard tip. The third and fourth 

impingers must be of the GreenburgSmith design, modified by replacing 

the tip with 1.3 cm (1/2 in.) ID glass 

tube extending to about 1.3 cm (1/2 

in.) from the bottom of the flask. 

Acceptable modifications include the 

following: using flexible connections 

between the impingers, using materials 

other than glass, or using flexible 

vacuum lines to connect the probe to 

the impinger train. 

The first and second impingers contain 

100 ml of deionized water, the third 

is empty and the fourth contains a 

known weight of silica gel, or 

equivalent desiccant. Place a 

5.3 - 8 
thermometer capable of measuring 

temperature to within 1oC (2oF) at the 

outlet of the fourth impinger to 

monitor outlet gas temperature. 

Instead of using silica gel the 

moisture leaving the third impinger 

may be measured by monitoring the 

temperature and pressure at the exit 

of the impinger train and using 

Dalton's law of partial pressures. 

Even if one uses means other than 

silica gel to determine the amount of 

moisture leaving the impinger train, 

silica gel, or equivalent should be 

used between the impinger system and 

pump to prevent moisture condensation 

in the pump and metering devices. 

g. Metering System 

The metering system includes vacuum 

gauge, leak-free pump, thermometers 

capable of measuring temperature to 

within 3oC (5.4oF), dry gas meter 

5.3 - 9 
capable of measuring volume to within 

2 percent, and related equipment, as 

shown in Figure 5.3-2. An alternative 

to the thermometers and dry gas meters 

is an equivalent temperaturecompensated dry gas meter. When the 

metering system is used in conjunction 

with a Pitot tube, the system shall 

allow for checks of isokinetic 

sampling rates. 

2.1.2 Barometer 

 A mercury, aneroid, or other barometer 

capable of measuring atmospheric pressure 

to within 2.5 mm (0.1 in.) Hg may be used. 

Alternatively, the barometric reading may 

be obtained from a nearby National Weather 

Service station. Request the station 

value (which is the absolute barometric 

pressure) and adjust for elevation 

difference between the NWS station and the 

sampling point at the rate of minus 2.5 mm 

(0.1 in.) Hg per 30 m (100 ft) elevation 

increase or plus the same adjustment for 

elevation decrease. 

5.3 - 10 
2.1.3 Temperature Determination Equipment 

Use the temperature sensor described in 

Method 2.1. Preferably the temperature 

sensor should be permanently attached to 

the Pitot tube or sampling probe so that 

the tip of the sensor extends beyond the 

leading edge of the probe sheath and 

touches no metal. Alternatively, the 

sensor may be attached just prior to use 

in the field. If the temperature sensor 

is attached in the field, place it in an 

interference-free arrangement with respect 

to the S-type Pitot tube openings (see 

Method 2.1). As another alternative, if a 

difference of not more than 1 percent in 

the average velocity measurement and 

resulting stack flow rate calculation 

would be introduced, the temperature 

gauge need not be attached to the probe or 

Pitot tube. 

2.1.4 Sulfuric Acid Determination Equipment 

Same as Method 6.1. If the process is 

steady state and sulfuric acid is less 

5.3 - 11 
than 10 percent of the standard for the 

applicable rule, concurrent sampling is 

not required. 

2.1.5 Gas Molecular Weight Determination 

Equipment 

Same as Method 3.1. Concurrent 

determination is not required when the 

process is steady state and the molecular 

weight varies less than 2 percent. 

2.2 Sampling Reagents 

a. Filters 

Glass fiber filters, without organic binder. 

The filters should be at least 99.95 percent 

efficient (< 0.05 percent penetration) on 

0.3-micron dioctyl phthalate smoke particles. 

The filter efficiency test must be conducted 

in accordance with ASTM Standard Method 

D-2986-71 or use data from the supplier's 

quality control program. Low sodium filters 

are recommended when SO2 is present. 

 

5.3 - 12 
b. Silica Gel 

Indicating-type, 6 to 16 mesh. Use new 

silica gel as received. If previously used, 

dry at 175oC (350oF) for 2 hours. 

c. Water 

Deionized, distilled water to conform to ASTM 

specification D1193-77 or D1193-91, Type 3. 

At the option of the chemist, the KMnO4 test 

for oxidizable matter may be eliminated when 

high concentrations of organic matter are not 

expected to be present. Reference to water 

throughout this method implies deionized, 

distilled water. 

Run blanks prior to field use to eliminate a 

high blank on test samples. 

d. Crushed Ice or Dry Ice Pellets 

e. Stopcock Grease 

Stopcock grease is not recommended and not 

necessary if screw-on connectors with Teflon 

5.3 - 13 
sleeves or similar are used. Acetoneinsoluble, heat-stable silicone grease may be 

used. Other types of grease may be used, 

subject to the approval of the Executive 

Officer. 

2.3 Pretest Determinations 

Select the sampling site and the minimum number 

of sampling points according to Method 1.1. If 

it is not possible to follow Method 1.1, or more 

than one sample site must be tested, see Chapter 

X. Determine the stack pressure, temperature and 

the range of velocity heads using Method 2.1. 

Determine the moisture content, using Method 4.1 

or it alternative, to make sampling rate 

settings. 

Determine the stack gas dry molecular weight, as 

described in Method 3.1. If integrated sampling 

(Method 3.1) is used for molecular weight 

determination, take the integrated bag sample 

throughout the total time of the particulate 

sample run, unless the effect on the velocity 

measurement and resulting stack flow rate 

5.3 - 14 
calculation is less than 1 percent. In that case 

take the integrated sample immediately before, 

after, or for a shorter time during the 

particulate sample run. 

Select a nozzle size based on the range of 

velocity heads, so that it is not necessary to 

change the nozzle size to maintain isokinetic 

sampling rates. Do not change the nozzle size 

during the run. Choose the differential pressure 

gauge appropriate for the range of velocity heads 

encountered (see Method 2.1). 

Select a probe length suitable for sampling all 

traverse points. Consider sampling large stacks 

from opposite sides (four sampling port holes) to 

reduce probe lengths. 

Select a total sampling time equal to or greater 

than the minimum total sampling time specified in 

the test procedures for the specific industry. 

The sampling time per point must not be less than 

2 minutes and the total sample volume taken 

(corrected to standard conditions) must not be 

less that 30 ft3. 

5.3 - 15 
To avoid timekeeping errors, the number of 

minutes sampled at each point should be an 

integer or an integer plus one-half minute. The 

sampling time should be the same at each point. 

In some circumstances, e.g. batch cycles, it may 

be necessary to sample for shorter times at the 

traverse points, resulting in smaller gas sample 

volumes. In these cases, test two or more 

cycles. 

Make a projected-area model of the probe 

extension-filter holder assembly, with the Pitot 

tube face openings positioned along the 

centerline of the stack, as shown in Figure 

5.3-1. Calculate the estimated cross-section 

blockage as shown. If the blockage exceeds 5 

percent of the duct cross sectional area, either 

(1) use a suitable out-of-stack filtration method 

instead of in-stack filtration; or (2) use a 

special in-stack arrangement with separate 

sampling and velocity measurement sites. 

2.4 Gas Volume Meter Checks 

 

 Check the meter against the −H@ orifice 

calibration obtained in Chapter III without the 

5.3 - 16 
probe, filter, and train connected. A pretest 

check is recommended. A post test check is 

mandatory. 

 Check calibration of the metering system by 

performing calibration runs at three different 

flow rates. Set flow rates at 0.4 CFM + 10 

percent, 0.75 CFM + 10 percent, and 1.0 CFM + 10 

percent. The calibration will be used to 

calculate −H@ at these three flow rates, where 

 −H@ is calculated as follows: 

 TmO2

 ∆H@ = 0.0319 ∆H --------------- 

 Pbar (Y2Vm

2A2) 

 where: 

 ∆H@ = Average pressure differential across 

 the orifice meter, in. H2O at 0.75 

 scfm (528oF, 29.92 in. Hg) 

 Tm = Absolute average dry gas meter 

 temperature, oR 

 Pbar = Barometric pressure, in. Hg 

 O = Total sampling time, min 

5.3 - 17 
 Y = Dry gas meter calibration factor, 

 dimensionless, obtained from 

 Chapter III 

 ∆H = Pressure differential across the 

 orifice, in. H2O 

 Vm = Volume of gas sample as measured by 

 dry gas meter, dcf 

0.0319 = (0.0567 in. Hg/oR) x (0.75 cfm)2

A = 1, if meter is not temperature 

 compensated 

 Tm = ---------------------- Compensated Temp. (oR) 

 if temperature compensated 

If the measured −H@ differs by more than + 3 

percent of the actual −H@ obtained in Chapter 

III, the results of the tests are voided. 

5.3 - 18 
Alternative procedure e.g. using an orifice meter 

with a known K-factor may be used, subject to the 

approval of the Executive Office. 

2.5 Pretest Preparation 

Set up the train as in Figure 5.3-2. 

Mark the probe with heat-resistant tape or by 

some other method to denote the proper distance 

to insert the probe into the stack or duct for 

each sampling point. 

Place crushed ice or dry ice pellets around the 

impingers. 

2.6 Leak Checks 

2.6.1 Pretest Leak Check 

After the sampling train has been 

assembled, plug the inlet to the probe 

nozzle with a material able to withstand 

the stack temperature. Insert the filter 

holder into the stack and wait 

approximately 5 minutes, or longer if 

necessary, to allow the system to come to 

5.3 - 19 
equilibrium with the stack gas 

temperature. Turn on the pump and draw a 

vacuum of at least 380 mm (15 in.) Hg; a 

lower vacuum may be used if it is not 

exceeded during the test. Determine the 

leakage rate. A leakage rate in excess of 

either 4 percent of the average sampling 

rate or 0.00057 m3 minute (0.02 cfm), is 

unacceptable. 

Start the pump with the bypass valve fully 

open and the coarse adjust valve 

completely closed. Partially open the 

coarse adjust valve and slowly close the 

bypass valve until the desired vacuum is 

reached. Do not reverse direction of 

bypass valve. If the desired vacuum is 

exceeded, either leak check at this higher 

vacuum or end the leak check as shown 

below and start over. 

When the leak check is completed, slowly 

remove the plug from the inlet to the 

probe nozzle and immediately turn off the 

vacuum pump. This prevents water from 

being forced backward and keeps silica gel 

5.3 - 20 
from being entrained backward. Perform 

leak check of Pitot lines (see Method 

2.1). 

2.6.2 Leak Check During Sample Run 

If a component change (e.g. filter 

assembly or impinger) becomes necessary 

during the sampling run, conduct a leak 

check immediately before the change is 

made. Use the pretest leak check 

procedure, but use a vacuum equal to or 

greater than the maximum value recorded up 

to that point in the test. 

If the leakage rate is is not greater than 

either 0.00057 m3/min (0.02 cfm) or 4 

percent of the average sampling rate, the 

results are acceptable, and no correction 

has to be applied to the total volume of 

dry gas metered. However, if leakage 

rate exceeds either of these limits, the 

tester must either record the leakage rate 

and correct the sample volume as shown in 

Chapter X, or void the sampling run. 

5.3 - 21 
Immediately after component changes, 

perform pretest leak check. 

2.6.3 Post Test Leak Check 

A leak check is mandatory at the 

conclusion of each sampling run. Follow 

the procedures outlined in Section 2.6.1, 

at a vacuum equal to or greater than the 

maximum value reached during the sampling 

run. Compare the leakage rate to limits 

indicated in Section 2.6.2 and follow the 

procedure described there. 

2.7 Sampling Train Operation 

During the sampling run, maintain an isokinetic 

sampling rate within 10 percent of true 

isokinetic. Maintain ice in the ice bath. 

For each run, record the data required on the 

data sheet shown in Figure 5.3-3. Be sure to 

record the initial dry gas meter reading. Record 

the dry gas meter readings at the beginning and 

end of each sampling time increment, when changes 

5.3 - 22 
in flow rates are made, before and after each 

leak check, and when sampling is halted. 

Record other data required by the sheet in Figure 

5.3-3 at least once for each sample point during 

each time increment. Take additional readings 

when significant changes (20 per cent variation 

in velocity head readings) require adjustments in 

flow rate. 

Level and zero the manometer and make periodic 

checks during the traverse, because the manometer 

level and zero may drift due to vibrations and 

temperature changes. 

During the period before sampling, the nozzle can 

be pointed downstream. Clean the portholes prior 

to the test run to minimize the chance of 

contamination. To begin sampling, remove the 

nozzle cap and verify that the Pitot tube and 

probe extension are properly positioned. 

 

 Position the nozzle at the first traverse point 

and rotate the nozzle until the tip is pointing 

directly into the gas stream before turning an 

the sampling pump. Immediately start the pump 

and adjust the flow to isokinetic conditions. 

5.3 - 23 
Use calculators or nomographs to expedite 

adjustment of the isokinetic sampling rate. 

When the stack is under significant negative 

pressure (height of water in impinger stem), take 

care to close the coarse adjust valve before 

inserting the probe into the stack to prevent 

water from backing into the filter holder. If 

necessary the pump may be turned on with the 

coarse adjust valve closed. 

When the probe is in position, block off the 

openings around the probe and porthole to prevent 

unrepresentative dilution of the gas stream. 

If needed, start the H2SO4.2H2O sample train 

following procedures outlined in Method 6.1. 

Traverse the stack cross section, as required by 

Method 1.1. Be careful to avoid bumping the 

probe nozzle into the stack walls when sampling 

near the walls or when moving the probe through 

the portholes. This minimizes the chance of 

extracting stack deposits. 

5.3 - 24 
During the test run, add more ice to maintain a 

temperature less than 15oC (60oF) at the 

condenser/silica gel outlet. Also periodically 

check the level and zero of the manometer. Note 

and investigate any changes in stack temperature 

or velocity pressure over those measured during 

previous tests or traverses. Changes can mean 

failure of sampling equipment or a change in the 

source. 

If the pressure drop of the filter becomes too 

high, making isokinetic sampling difficult to 

maintain, the filter may be replaced during a 

sample run. Use another complete filter assembly 

rather than attempt to change the filter itself. 

Before a new filter assembly is installed, 

conduct a leak check (see Section 2.6.2). 

The total particulate weight includes the 

summation of all filter assembly catches. Use a 

single train for the entire sample run, except 

cases when sampling is required in two or more 

ducts or at two or more locations within the same 

duct, or when equipment failure necessitates a 

change of trains. When two or more trains are 

used, perform separate analyses of the front-half 

5.3 - 25 
and impinger catches from each train must be 

performed. 

At the end of the sample run, turn off the coarse 

adjust valve, remove the probe and nozzle from 

the stack, turn off the pump, record the final 

dry gas meter reading, and conduct a post test 

leak check as outlined in Section 2.6.3. 

Also, leak check Pitot lines as described in 

Method 2.1. The lines must pass this leak check 

to validate the velocity head data. Calibrate 

the meter as described in Section 2.4. 

2.8 Calculation of Percent Isokinetic 

Calculate percent isokinetic using the equation 

shown in Figure 5.3-5 to determine whether the 

run was valid or another test run should be made. 

2.9 Sample Handling 

Proper clean-up procedure begins as soon as the 

probe is removed from the stack at the end of the 

sampling period. 

5.3 - 26 
Allow the probe to cool. When the probe can be 

safely handled, wipe off all external particulate 

matter near the tip of the probe nozzle and place 

a cap over it to prevent losing or gaining 

particulate matter. Do not cap off the probe tip 

tightly while the sampling train is cooling down. 

This would create a vacuum in the filter holder, 

drawing water from the impingers into the filter. 

Before moving the sample train to the clean-up 

site, remove the probe from the sample train, 

wipe off any stopcock grease, and cap the open 

outlets of the probe. Be careful not to lose any 

condensate that might be present. Remove the 

umbilical cord from the last impinger and cap the 

impinger. If a flexible line is used between the 

first impinger and the probe, disconnect the line 

at the probe and let any condensed water or 

liquid drain into the impingers or condenser. 

After wiping off any stopcock grease, cap off the 

probe outlet and impinger inlet. Either groundglass stoppers, plastic caps, or serum caps may 

be used to close these openings. 

Transfer the probe, filter, and impinger assembly 

to the clean-up area. This area should be clean 

5.3 - 27 
and protected from the wind to reduce chances of 

contaminating or losing the sample. It is 

recommended that sample recovery be performed in 

a controlled laboratory environment. 

2.10 Calibrations 

 See Chapter III.

5.3 - 28 
METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

Section 3 of 4 

3. Laboratory Procedures 

3.1 Apparatus 

3.1.1 Sampling Train 

See Section 2.1. 

 3.1.2 Sample Recovery 

See Method 5.1, Section 3.1.2. 

3.1.3 Analysis of Particulate Matter 

See Method 5.1, Section 3.1.3. 

3.1.4 Acid and Sulfate Analysis 

See Method 5.1, Section 3.1.4. 

5.3 - 29 
 3.2 Reagents 

See Method 5.1, Section 3.2. 

 3.3 Pretest Preparation 

See Method 5.1, Section 3.3. 

3.4 Preparation of Sample Collection Train 

Assemble the train as shown in Figure 5.2-1. 

Follow the loading and connection procedures 

found in Method 5.1, Section 3.3. 

 3.5 Leak Check 

The sample collection train may be leak checked 

in the laboratory after assembly following the 

procedures found in Section 2.5. 

3.6 Sample Recovery 

Recover the sample in three fractions: 

filter, prefilter, and post-filter. 

5.3 - 30 
3.6.1 Prefilter Fraction 

This includes the nozzle and front half of 

the filter holder. Recover this fraction 

using the procedures outlined in Section 

3.6.2, Method 5.1. 

3.6.2 Filter Fraction 

Recover the filter using the procedures 

outlined in Section 3.6.1, Method 5.1. 

3.6.3 Post-Filter 

This consists of the back half of the 

filter holder, the probe, first three 

impingers and any connectors. Measure the 

moisture gain using Method 4.1, and 

recover this fraction using the procedures 

outlined in Section 3.6.2 and 3.6.3, 

Method 5.1. 

3.7 Sample Analysis 

5.3 - 31 
The three fractions are analyzed separately using 

procedures outlined in Section, 3.7, Method 5.1. 

3.7.1 Prefilter 

Analyze the prefilter fraction for total 

residue weight, acid content and, sulfate 

content. Organic extraction is not 

performed on this fraction because organic 

compounds do not normally deposit on 

heated train components. 

3.7.2 Filter 

Weigh the filter to constant weight and 

analyze for acid and sulfate if necessary. 

3.7.3 Post-Filter 

Analyze the post-filter catch for organic 

residue (if required), aqueous or total 

residue, acid and sulfate. 

NOTE: This fraction represents 

"condensable" particulates i.e. compounds 

which condense at ambient conditions and 

5.3 - 32 
particulates <0.3 microns in diameter. 

Filtration for insolubles is not normally 

required before organic extraction, since 

the up-filter catches most insoluble 

particulates. 

3.8 Calculations and Reporting 

Calculations are carried out as in Method 5.1. 

Results are reported as follows: 

Total Impinger Volume, ml (g) 

Impinger Gain, ml (g) 

Silica Gel Gain, ml (g) 

Pre-Filter Recovered Volume, ml (g) 

 Residue, mg 

 Acid, as H2SO4.2H2O, mg 

 Sulfate, as H2SO4.2H2O, mg 

Filter Catch, mg 

 Acid, as H2SO4.2H2O, mg 

 Sulfate, as H2SO.2H2O, mg 

Post-Filter Recovered Volume, ml (g) 

Organic Residue, mg 

Aqueous (or Total) Residue, mg 

 Acid, as H2SO4.2H2O, mg 

 Sulfate, as H2SO4.2H2O, mg 

5.3 - 33 
 3.9 Calibrations 

See Method 5.1, Section 3.9 

5.3 - 34 
METHOD 5.3 

DETERMINATION OF PARTICULATE MATTER EMISSIONS FROM 

STATIONARY SOURCES USING AN IN-STACK FILTER 

Section 4 of 4 

4. Engineering Calculations and Reporting 

 4.1 Calculations 

Carry out calculations, retaining at least one 

decimal figure more than that of the acquired 

data. Round off figures after the final 

calculation. Other forms of the equations may be 

used as long as they give equivalent results. 

See Figures 5.3-4 and 5.3-5 

5.3 - 35 
5.3 - 36
5.3 - 37
5.3 - 38
5.3 - 39
5.3 - 40