( Adopted: 1/ 9/76; Amended: 4/1/77; Amended: 8/5/77; Amended: 4/6/79; Amended: 8 / 7/81; Readopted by Statute: 07/01/97; Readopted by Statute:

01/01/02; Amended: 5/17/05)

AVAQMD RULE 218 218

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Stack Monitoring 

## RULE 218

Stack Monitoring

(A) Stack Monitoring Requirements

(1) The owner or operator of any equipment described below shall provide; properly install, maintain in calibration, in good working order and in operation; approved stack monitoring systems to m

easure the concentration of the following air contaminants and diluent gases in the emissions from the sources indicated. The owner or operator shall also provide any other data necessary for calculating air contaminant emission rates.

(a) Oxides of nitro gen (NO

x ), and carbon dioxide (CO 2 ) or oxygen (0 2 ), from steam generators with a heat input of 63 million kilogram calories (250 million British Thermal Units) or more per hour and with a use factor of at least thirty percent (30%).

(b) Sulfur dioxide (SO 2 ) from steam generators with a heat input of 63 million kilogram calories (250 million British Thermal Units) or more per hour and with a use factor of at least thirty percent (30%) if control equipment is used.

(c) Oxides of nitrogen (NO

x ) from all nitric acid production plants.

(d) Gaseous sulfur compounds calculated as sulfur dioxide (SO 2 ) from all sulfuric acid production plants, carbon monoxide boilers or furnaces of the regenerators of fluid catalytic cracking units, and all fluid cokers.

(e) Sulfur d

ioxide (SO 2 ) from sulfur recovery plants with oxidizing tail gas units, and with reducing tail gas units using continuous incineration for control of hydrogen sulfide (H

2 S).

(2) The Air Pollution Control Officer (APCO) may require a person to provide, prop erly install, maintain in calibration, in good working order and in operation, an approved stack monitoring system to measure air contaminants in emission gases when that person installs, operates, or uses any equipment which emits 900,000 kilograms (992 t ons) or more per year of carbon monoxide (CO) or 90,000 kilograms (99 tons) or more per year of any air contaminant except carbon monoxide (CO). The APCO shall report to the District Board in writing when he requires the installation of a stack monitoring system under the provisions of this subpart.



### (B) Approval of Monitoring Systems218

- 2 AVAQMD RULE 218 Stack Monitoring (1) All monitoring systems to be installed after April 6, 1979, require an initial approval by theAPCO, prior to installation. The APCO shall act upon an application for ini

tial approval within 30 days after filing or within thirty (30) days after the applicant furnishes further information, plans and specifications requested to complete an application. Upon completion of installation, a person operating or using a stack mon itoring system shall undertake a series of tests to demonstrate the acceptability of the system's performance pursuant to (C) below. Within six (6) months of initial operation, data from such tests shall be submitted to the APCO for approval. If satisfac tory performance is demonstrated, a final approval of the system shall be granted.

(2) A person operating a monitoring system installed on or before April 6, 1979, shall, by June 1, 1979, submit a plan to the APCO outlining steps to achieve compliance with

the performance specifications of (C) below as expeditiously as practicable, but in no event later than March 2, 1981.

Each plan shall include, but shall not necessarily be limited to, dates and methods for achieving the following increments of progress:

1. Submit test results.

2. Negotiate and sign contracts.

3. Commence modification or replacement of non

- complying systems.

4. Complete modification or replacement of non

- complying systems.

5. Submit final test results.

6. Achieve final compliance with (C) below on or before March 2, 1981.

Non

- complying systems shall be operated at the level of performance indicated by test results. Each system shall be operated in accordance with the plan.

(3) A person operating an approved monitoring system shall affix such written notice of approval or a legible facsimile upon the equipment in a manner such that it is clearly visible and legible. In the event that the equipment is so 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 theAPCO.



### (C) Monitoring System Standards

(1) The monitoring system shall be installed at a location such that air contaminant and diluent gas concentration measurements can be made which are representative of the stack emissions of the affected facility.

(2) Prior to final approval of the monitoring system, it shall meet, and it shall thereafter be operated in accordance with, the following performance and equipment spec ifications:AVAQMD RULE 218 218

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Stack Mon itoring (a) Monitors for Gaseous Air Contaminants

Parameter Specifications (i) Operational Period* Greater than or equal to 168 hours. (ii) Calibration Error** Less than or equal to 5 percent. (iii) Response Time Less than or equal to 10 minutes. (iv) Zero Drift (2

- hour)** Less than or equal to 2 percent of full scale reading. (v) Zero Drift**(24

- hour) Less than or equal to 2 percent of full scale reading. (vi) Calibration Drift (2

- hour)** Less than or equal to 2 percent of scale reading. (vii) Calibration Drift (24

- hour)** Less than or equal to 2.5 percent of full scale reading. (viii) Relative Accuracy** Less than or equal to 20 percent of the mean

value of the reference method test data or less than or equal to 10 percent of the allowed

conce ntration, whichever is greater.

(b) Monitors for Diluent Gases

Parameter Specifications (i) Operational Period* Greater than or equal to 168 hours. (ii) Calibration Error** Less than or equal to 5 percent. (iii) Response Time Less than or equal to 10 minutes. (iv) Zero Drift (2

- hour)** Less than or equal to 0.4 percent CO 2 or 0 2

. (v) Zero Drift (24

- hour)** Less than or equal to 0.5 percent CO 2 or 0 2

. (vi) Calibration Drift (2

- hour)** Less than or equal to 0.4 percent CO 2 or 0 2

. (vii) Calibration D

rift (24

- hour)** Less than or equal to 0.5 percent CO 2 or 0 2

.

(3) The monitoring system shall be operated according to the following standards:

(a) Calibration gases shall meet the following criteria:

(i) For gaseous air contaminant monitors, the mixture shall be certified to be within two percent (2%) of the stated value. (ii) For carbon dioxide and oxygen monitors, the mixture shall be certified

to be within two

- tenths percent (0.2%) carbon dioxide or oxygen of the stated value. Ambient air may be used for oxygen monitors if the span is higher than twenty one percent (21%) oxygen.

(b) Zero gases used shall meet the following criteria:

(i) For gaseous air contaminant monitors, the gas shall be certified by the manufacturer to contain less than 1 part pe r million of the air218

- 4 AVAQMD RULE 218 Stack Monitoring contaminant (except carbon monoxide, less than 10 parts per million), or alternately, ambient air may be used. (ii) For carbon dioxide and oxygen monitors, the gas shall be certified by the manufacturer to contain less than 100 parts p er million of carbon dioxide or oxygen.

(c) Calibration gases shall be manufactured, analyzed and certified according to USEPA Traceability Protocol for Assay and Certification of Gaseous

Calibration Standards (EPA

- 600/R97/121) as revised September 1997 o r any subsequent version as published by USEPA. [Suggested by comment letter of 03/17/2005. Derived from SCAQMD 218(a)(5)]

(d) Calibration checks shall be performed at least once each day at regular

intervals.

(e) The instrument full scale reading shall b e equivalent to approximately two hundred percent (200%) of the concentration limit specified in the applicable rule, or at a value approved by theAPCO. Oxygen and carbon dioxide instruments full scale readings shall be such that the full range of concent rations

encountered can be measured.

(f) Regular scheduled maintenance of the monitoring system shall be deferred until the report required under Section (E)(2) is made, if the system is measuring a concentration equal to or exceeding the emission standard , and if such deferral will not reasonably be expected to result in damage to the system.

(g) The monitoring system shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording), for each successive fifteen (15) minute period

.

(h) The requirements of section (C)(3)(g) shall not apply to the following conditions:

(i) Regular calibration checks of the system. (ii) Routine maintenance and repair of sixty (60) minutes or less duration. (4) Following final approval, if significant modifications are made to the system, a demonstration of the ability of the system to operate in accordance with the specifications of (c)(2) may be required at the discretion of the Executive Officer.

(5) Span cell calibration techniques may be employed w ith in situ monitors, not extracting the gas sample from the stack if the criteria of (c)(2)(A)(ii), (vi) and (vii) can be met and if the use of the cell provides a check of all analyzer internal mirrors and lenses and all electronic circuitry including th e source and detector assembly which are normally used in sampling and analysis.AVAQMD RULE 218 218

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Stack Mon itoring (6) Zero calibration reflector techniques may be employed with in situ monitors, not extracting the gas sample from the stack, if the criteria of (c)(2)(A)(iv) and (v) can be

met.



### (D) Retention of Records

(1) The records of the data obtained from the recording devices of the stack monitoring system shall clearly indicate concentrations as specified by theAPCO. Records shall be maintained by the owner or operator of a monitorin g system for a period of at least two (2) years and shall be made available to the APCO upon request.

(2) All records of the occurrence and duration of any start up, shutdown or malfunction, performance test, evaluation, calibration, adjustment and mainten ance of the monitoring system as well as calibration gas traceability or span cell specifications documents, shall be retained by the monitoring system operator for a period of at least two (2) years and shall be made available to the APCO upon request.



### (E ) Reporting

(1) A person operating a stack monitoring system shall provide a summary of the concentration and emission data obtained from such system, as well as any additional information specified by the APCO to evaluate the accuracy and precision of the measurements. The summary shall be submitted monthly to the APCO within thirty (30) days of the end of the month being reported, in the form and manner prescribed by him. The summary shall be available for public inspection at the office of the Air Qual ity Management District.

(2) A person operating a monitoring system shall report any concentration level in excess of the regulated limit to the APCO within ninety

- six (96) hours after such occurrence in the form and manner prescribed by him. The report s hall include the following information:

(a) Time intervals, date, and magnitude of the excess concentration level; nature and cause of the excess (if known), corrective actions taken and preventive measure adopted.

(b) Averaging period used for data report ing shall correspond to the averaging period specified in the rule governing the concentration limit in question.

(3) Reports of Monitoring System Failure or Shutdown

(a) A person operating a monitoring system shall notify the Executive Officer within

nine ty

- six (96) hours, in a form and manner prescribed by him, in the event of a system failure or shutdown for repair, which exceeds sixty (60) consecutive minutes. Zero and calibration checks and routine maintenance do not require reporting.218

- 6 AVAQMD RULE 218 Stack Monitoring (b) In the case

of a monitoring system failure or shutdown for repair, compliance with the provisions of subsection (a) is waived for a period not to exceed ninety

- six (96) consecutive hours. Such waiver is extended beyond ninety

- six (96_ consecutive hours only if a pet ition 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.



### (F) Exemption

Any source subject to the provisions of (a)(1) above may obtain an exemption from the

p rovisions of (a)(1) above upon demonstration to the satisfaction of the APCO that the source is not subject to a District rule or regulation prohibiting or limiting the discharge of any air contaminants which are the subject of (a)(1).



### (G) Definitions

(1) Calibration

- An operating condition of the monitoring system whereby the system is accurately recording the concentration of the specific air contaminant or diluent gas as evidenced by calibration checks, achieved by periodic manual or automatic adjustmen t.

(2) Calibration Check

- A procedure to determine the response of the system to a given gaseous compound concentration by means of injecting a certified calibration gas mixture into the system, or the insertion of a span cell into the internal light path of the analyzer.

(3) Calibration Drift**

- The change in the monitoring system output over a stated time period of normal continuous operation when the air contaminant or diluent gas concentration at the time of the measurements is the same known upscale value, or simulated to be the same upscale value by use of a span cell.

(4) Calibration Error**

- The difference between the air contaminant or diluent gas concentration indicated by the monitoring system and the known concentration of the span gas or the equivalent rating of the span cell.

(5) Calibration Gas

- A mixture of the air contaminant gas, or carbon dioxide or oxygen in a diluent gas, which, when periodically introduced into the monitoring system, is used to check that system's accuracy.

(6) Certi

fied Gas Mixture

- A mixture analyzed, by replicate samples, by the manufacturer by referring to National Bureau of Standards Reference Materials, such that a statement of the precision of the analysis can be made.

(7) Diluent Gas

- A gas present in a cali bration gas mixture or in the emissions from a source which is present in quantities significantly larger than the air contaminant.AVAQMD RULE 218 218

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Stack Mon itoring (8) Ninety

- Five Percent Confidence Interval

- The statistically determined range within which there is a ninety

- five percent (95%) probability all values determined will lie.

(9) Operational Period

- A minimum period of time during which the monitoring system shall operate, according to the performance and equipment specifications, without unscheduled maintenance, repair, or ad justment.

(10) Parts Per Million

- A volume concentration measurement, indicating the volumetric quantity of the gas in question, dispersed in one million volumes of gas mixture, reported on a dry basis.

(11) Reference Method

- The official test method emp loyed by the District to determine compliance with the rules.

(12) Relative Accuracy

- The degree of correctness with which the monitoring system yields the value of gas concentration of a sample relative to the value given by the reference

method or to th

e allowed concentration. This accuracy is expressed in terms of error, which is the absolute value of the mean of the differences between the pared concentration measurements plus the absolute value of the ninety

- five percent (95%)

confidence interval. I

t is expressed as a percentage of the mean reference method value or of the allowed concentration. When a rule requires a correction of the air contaminant concentration to a specific O 2 or CO 2 concentration, the relative accuracy requirement shall apply to the corrected concentration value.

(13) Response Time

- The time interval from a step change in the air contaminant or gas diluent concentration at the input to the monitoring system to the time at which ninety

five percent (95%) of the corresponding fi nal value is reached as displayed on the monitoring system data recorder.

(14) Routine Maintenance

- An operation, recommended by the manufacturer, to be performed at specified intervals, to preclude system failure. Repairs to a malfunctioning
system are excluded from this definition.

(15) Span Cell

- A sealed cell of fixed length, containing a known concentration of an air contaminant, which is inserted into the internal light path of the analyzer to provide a measurement output that corresponds to a know n concentration of that air contaminant.

(16) Stack Monitoring System, or Monitoring System

- The total equipment required for the determination of concentrations of air contaminants and diluent gases in a source effluent. The system consists of three maj or subsystems:

(a) Sampling Interface

- that portion of the monitoring system that performs one or more of the following operations: delineation, acquisition, transportation, and conditioning of a sample of the source effluent or protection of the analyzer from the hostile aspects of the sample or source environment.218

- 8 AVAQMD RULE 218 Stack Monitoring (b) Analyzer

(i) Air Contaminant Analyzer

- that portion of the monitoring system that senses the air contaminant and generates a signal output that is a function of the concentration of that g as. (ii) Diluent Analyzer

- that portion of the monitoring system that senses the concentration of oxygen or carbon dioxide and generates a signal output that is a function of the concentration of that gas. This subsystem is required only for sources note d in a (a)(1)(A).

(c) Data Recorder

- that portion of the monitoring system that provides a permanent record of the output signal in terms of concentration units, including additional equipment such as computers required to convert the original

recorded v

alue to any value required for reporting.

(17) System Failure

- occurs anytime the monitoring system is suspected or known to be unable to meet the requirements of (c)(2) or (b)(2), as applicable.

(18) Use Factor

- The amount of time used per year divided by the amount of time available for use per year, expressed as a percent.

(19) Zero Calibration Reflector

- A device which is inserted into the internal light path of the analyzer to provide a measurement output that simulates a zero gas concentration.

(20 ) Zero Drift**

- The change in the monitoring system over a stated period of time of normal continuous operation when the air contaminant or diluent gas concentration at the time of the measurements is zero, or is simulated to be zero by use of a zero

cali bration reflector.

(21) Zero Gas

- Agas containing less than a specified amount of the air contaminant or diluent gas which, when periodically injected into the monitoring system, is used to check that system's response to the absence of the air contaminan t or diluent gas.

*The operational period test performed prior to final approval shall be preceded by a one hundred sixty eight (168) hour (minimum) conditioning period during which the system shall be operated without unscheduled maintenance, repair, or adjustment.

**Expressed as the sum of the mean value plus the ninety

- five percent (95%)

confidence interval of a series of tests.

[SIP: Approved 7/6/82, 47 FR 29231, 40 CFR 52.220(c)(103)(xviii)(A); Approved 9/28/81, 46 FR 47451, 40 CFR 52.220(c)(65)(i i); Approved ________, _________, 40 CFR 52.220(c)(42)(xiv)(A); Approved 9/8/78, 43 FR 40011, 40 CFR 52.220(c)(39)(iii)(C)]AVAQMD RULE 218 218

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