(Adopted 

### May 14,1999)



# - RULE 218.1. CONTINUOUS EMISSION MONITORING PERFORMANCE SPECIFICATIONS (a) Definitions (1) ANALYZER 

### - the part of the continuous emission monitoring system (CEMS) that analyzes the appropriate gaseous constituents ofthe 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 concentrations 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 as represents those concentrationsin 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 flowrate and all essential measurement sub-system parameters. (D) Stack Flowmeter -. the part of the CEMS that detects the parameters fiom 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 ofthe stack gas volumetric flow rate and all essential measurement subsystem parameters. 

### (2) CALIBRATION 

### - a procedure performed to ensure that the CEMS accurately

measures and records the concentration of the specific air contaminant or diluent gas, flow rate and other parameters necessary to generate the required data, as evidenced by calibration checks and achieved by periodic manual or automatic adjustment. 

### (3) CALIBRATION CHECK 

### - a procedure performed to determine CEMS response to a given gaseous compound concentration by means of injecting a certified calibration gas mixture into the CEMS as close to the probe tip as practical. (4) CALIBRATION DRIFT (CD) 

### - change in the CEMS output or response over a specific period of normal continuous operation when the air contaminant or diluent gas concentration at the time of the measurements is the same known

Rule 218.1 

## - 1

### RULE 218.1 (Cont.) (Adopted

### May 14,199)



### upscale value. .CDis expressed as the sum ofthe absolute value of the mean difference and the absolute value of the confidence coefficient of a series of tests, to the hllspan range, expressed as a percentage as 

### follows:

CD =

## 121

+

# ICCI
x 100 

### FSR Where: FSR = 

### Full span range 

# ICC(
= 

### Absolute value ofthe 95%confidencecoefticient 

## 121 = 

### Absolute value of the mean difference. The mean difference,

## d,iscalculated as:

Where:

n 

## 1

di= 

### Algebraic sumofthe individual differencesdi i=1 

### n = 

### Number ofdatapoints di = 

### The difference between the paired response values ofthemonitoring system (5) CALIBRATION ERROR (CE) (A) 

### CALIBRATION ERROR 

### ,as applicable to Section (c), "Standards for Existing CEMS" 

### -the ratio ofthe differencebetween the aircontaminant

or diluent gas concentration indicated by the CEMS and the known concentration of the calibration gas, to the known concentration of the calibration gas. CE is calculated as the ratio of the sum ofthe absolute values of the mean difference and the 95 percent confidence coefficient ofa seriesoftests, to the gas concentration,expressedas 

### apercentage,as 

### follows:

CE =

# ldl+ lCCI x 100 

### C Where: C = 

### Calibration gas concentration

### RULE 218.1 (Cont.) (Adopted 

### May 14,199) 

# ICC~
= Absolute value ofthe 

### 95% confidencecoefficient 

## Id1 = Absolute value of the mean difference. The mean difference is calculated as:

Where:

n 

### di = Algebraic sum of the individual differencesdi i=l
n = Number of data pairs di = The difference between the paired monitoring system response value and the known gas concentration or the equivalent rating of the reference method value, both in units of the applicable standard 

### (B) CALIBRATION ERROR, as applicable to Section (b), "Standards for New or Modified CEMS" 

### - the ratio of the absolute value of the difference between the air contaminant or diluent gas concentration indicated by the CEMS and the known concentration of the calibration gas, to the full span range, expressed as a percentage, as follows. 

# IC-AI x 100 CE = --- FSR Where: C = Calibration gas concentration A = Actual response or the concentration indicated by the monitoring system FSR = Full span range ofthe instrument 

### (6) CEMS AVAILABILITY PERCENTAGE 

### - a percentage calculated as the ratio of the total unit operating hours for which the CEMS provided qualityassured data, to the sourcetotal unit operating hours during a specified period, excluding periods of calibration, maintenance, repair, or audit, up to a maximum of

### 40 hours permonth. (7) CERTIFIED CEMS 

### - a CEMS installed, tested, operated, maintained, and calibrated according to the applicable requirements of Rules 218 and 218.1; that has met the applicable performance specifications of Rule 218.1 and, has

### RULE 

### 218.1 (Cont.) (Adopted May 14,199)

received written approval and conditions thereto applying, from the Executive Officer. (8) 

### CERTIFIED GAS MIXTURE 

### - a gas mixture manufactured, analyzed and certified in 

### accordance with the "EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards" 

### - EPA-600/R97/121, September 1997 Revision (EPA Traceability Protocol) or any subsequent version published by EPA. This definition incorporates by reference EPA Protocol. (9) CONFIDENCE COEFFICIENT (CC) 

### - the 2.5 percent error confidence coefficient for the 95 percent confidence interval of a series of tests. The CC is calculated asfollows:

Where: S

d = 

### Standarddeviation
n = 

### Number ofdata in a series of tests

b.975 = 

### t-value (see Table of t-Values below)

Table of t-Values*



## * The t-values in this table are already corrected for n-1 degreesof freedom. Use n equal to the number of data points. (10) CONTINUOUS EMISSION MONITORING SYSTEM (CEMS) 

### - the total combined equipment and systems required to continuously determine air contaminants and diluent gas concentrations andfor mass emission rate of a source effluent (as applicable). The CEMS consists of three major subsystems: sampling interface,analyzer and data acquisition system.

### RULE 218.1 (Cont.) (Adopted May 

### 14,199)

(11) CONTINUOUS MONITORING 

## - a monitoring in which a minimum of one measurement (e.g., concentration, mass emission, flow rate) is taken and recorded each minute. (12) 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 any other applicable parameter necessary to generate the required data in units of applicable standard. The DAS consists of al1,equipment such as a computer required to convert the original recorded values to any values required forreporting. (13) DILUENT GAS 

## - a gas present in a calibration gas mixture or in source emissions that is present in quantities significantly larger than the air contaminant. (14 ) 

### FULL SPAN RANGE 

### - the full range of values or data display output that a monitor component is calibratedtomeasure. (15) LINEARITY ERROR (LE) 

## - the percentage error in linearity expressed in terms ofthe ratio ofthe absolute value ofthe difference between the reference value and the mean CEMS response value, to the reference value. LE is calculated as follows:

Where:

- 

### C = 

### Mean ofthe CEMS response values R = 

### Certified gas concentration as reference value

(16) MODIFICATION REQUIRING RECERTIFICATION 

## - any change to the basic equipment, control equipment, contaminant concentration, interfering substances, or CEMS 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) isrequired.

### RULE 218.1 (Cont.) (Adopted May 14,199)

(17) NINETY-FIVE PERCENT CONFIDENCE INTERVAL 

### - the statistical estimation denoting a rangeofvalueswhich is expectedto include a true value with a 95 percent probability. (18)'OPERATIONAL PERIOD 

### - a minimum period of 168 continuous hours during which the CEMS shall operate, according to the manufacturer's written performance and equipment specifications, without unscheduled maintenance, repair, or adjustment. (19) QUALITY ASSURANCEIQUALITY 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 ofRules 218 and 218.1. (20) REFERENCE METHOD (RM) 

### - the official test method employed by the District to determine compliance with the rules or permit conditions. A list of reference methods is identified in Table 1. (21) RELATIVE ACCURACY (RA) 

### - the absolute mean difference between the gas concentration or emission rate determined by the CEMS and the value determined by the 

### RM plus 2.5 percent error of confidence coefficient of a series of tests, dividedby the mean ofthe 

### RM tests. (22) RELATIVEACCURACYAUDIT (RAA)

## - the RAtest expressed in terms of the ratio of the relative difference between the mean reference method value and the mean CEMS response value, to the mean value determined by the reference method or applicable standard for concentration, flow or mass emission rate. Unless otherwise specified, 

### RAA shall have the same specifications and requirements asthe RelativeAccuracy Test Audit (RATA), except that the 

### RAA shall require a minimum of three data sets. When a rule requires a correction of the air contaminant concentration to a specific 02or C02 concentration, the RA requirement shall apply to the corrected concentration value. The RA ofa RAA data set is calculated and expressed as a percentage as follows:

### RULE 218.1 (Cont.) (Adopted 

### May 14,199)

Where:

- 

### RM. = Mean of the values determined by the reference method or applicable standard 

### - r = Mean of the CEMSresponsevalues (23) RELATIVE ACCURACY TEST AUDIT (R4TA)

### - the 

### R4 test expressed in
terms of the ratio of the sum of the absolute mean difference between the CEMS-generated data and the value determined by the applicable reference method or applicable standard and the absolute confidencecoefficient, to the

mean of the reference method or applicable standard value for concentration, flow or mass emission rate. When a rule requires a correction of the air contaminant concentrationto a specific 02or C02concentration,the relative accuracy requirement shall apply to the corrected concentration value. The 

### R4 of a RATA data set is calculated and expressedas a percentageas follows:

Where: 

## Id1 = Absolutevalue ofthemean difference lCCl = Absolutevalue ofthe 95% confidence coefficient 

### RM = Average

### RM value or applicable standard

The arithetic mean of the difference, d, of a set of data is calculated as follows:

Where:

n 

### di = Algebraic sum of the individual differencesdi i=l di = The difference between the reference method value and CEMS value, both in units of the applicable standard
n = Number ofdata points (24) RESPONSE TIME 

## - the time interval from a step change in the air contaminant or gas diluent concentration to the time when 95 percent of the corresponding final value is reached as displayed on the CEMS data recorder or acquisition system. The response time is determined by introducing a

### RULE 218.1 (Cont.) (Adopted May 14,199)

certified gas mixture into the CEMS upstream of the sampling interface and

ascloseto theprobe inlet aspracticable. (25) 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. Repairsto amalhctioning system areexcluded from this definition. (26) SAMPLING INTERFACE 

### - that part of the CEMS that performs sample acquisition using one or more of the following operations: extraction, physicaVchemical separation, transportation or conditioning of a representative sample from a designated source. (27) SEMI-CONTINUOUS EMISSION MONITORING SYSTEM (SCEMS) 

## - the total combined equipment and systems required to semi-continuously determine air contaminants and diluent gas concentrations andlor mass emission rate of a source effluent (as applicable). The SCEMS 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 sensitizedtape analyzer, other sample integration based technologies, and time-shared CEMS. (28) SYSTEM BIAS 

## - the difference between the gas concentrations exhibited by the CEMS when a calibration gas is introduced at a location upstream of the sampling interface, and as close to the sampling probe inlet as practicable, and whenthe samecalibration gasis introduceddirectly to the analyzer. (29) SYSTEM FAILURE 

### - inability of the CEMS to meet the requirements of Rule 218.1. (30) TIME-SHARING 

### - a monitoring technique where an analyzer and possibly the associated sampleconditioning systemisused on more than one source. (31) ZERO CHECK- a procedure performed to determine the response of the CEMSto a given zero gas standardby means of injecting the zero gas into the CEMS as close to the probe tip aspractical. (32) ZERO DRIFT (ZD) is the change in the monitoring system outputfresponse 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. The values for ZD shall be expressed as the ratio of the sum of the absolute value of the mean of the difference between paired instrument

### RULE 218.1 (Cont.) (Adopted May 14,199)

response values and the absolute value of the CC, to the full span range, calculated as a percentage asfollows:

Where:

S = Full span range JCCI = Absolute value of the confidencecoefficient

. . 

## Id1 = Absolute value of the mean difference. The mean difference is calculated as:

Where:

n 

### di = Algebraic sum ofthe individual differences di i=l
n = Number of datapairs di = The difference between a pair of instrument response values (33) ZERO GAS 

### - a gas containing less than a specified amountofthe contaminant

or diluent gas which, when periodically injected into the CEMS, is used to check CEMS' responsetothe absence of the air contaminantor diluent gas.

(b) Standards for New or Modified CEMS In order to be a Certified CEMS, a CEMS subject to the provisions of Rule 218 Sections (c)(l), (d)(l)(C), (d)(l)(D)(i), (d)(2)(C) and (d)(2)(D), as applicable, shall meet the operational requirements, performance specifications, and standards 

### as follows: (1) Pre-Certification Testing Requirements for New or Modified CEMS Before any certification or relative accuracytest is performed,the CEMS shall
meet the following standards: (A) CEMS Location The CEMS shall be installed at a location that enables measurements of air contaminant and diluent gas concentration, and flow rates can be made which are representativeofthe stackemissionsofthe source. (B) Sampling Location

### RULE 218.1 (Cont.) (AdoptedMay 14,199)

The monitoring system sampling probe tip and the reference method sampling 'port locations shall be determined according to District Method 1.I. The monitoring sampling probe shall be located where a sample may be obtained which is representative ofthe source emissions. Each probe shall not interfere with the other when in use. Other locations may be chosen subject to a written approval of the Executive Officer. If an alternate location is chosen which does not conform with District Method 1.1, the absence of flow disturbance shall be demonstrated using the District method in the source Test Manual, Chapter X, Section 1.4 

## - "Alternative Site Selection Method", or 40 CFR, Part 60, Appendix A, Method 1, Section 2.5 

### - "Alternative Measurement Site Selection Procedure", and, the absence of stratification shall be demonstrated using the District method in the

sourceTest Manual, Chapter X, Section 13

### - "Determination of Gaseous Constituent Stratification". Alternatives to sampling site selection in the presence of stratification are presented in Rule 2 18.1 (b)(3)(C)(ii). (C) Full Span Range (FSR) (i) The FSR for mass emission rate, air contaminant, diluent and flow analyzers shall be set such that all data points are within 10 to 95 percent oftherange. (ii) For air contaminant monitors, the FSR shall be set between 150 and 200 percent of the concentration limit as specified in the applicable rule orpermit condition. The FSR may be set at a value other than that specified, but no lower than 120percent, provided that the CEMS owner or operator demonstrates to the satisfaction of the Executive Officer that the FSR will not be exceeded. Such demonstrations may include, but not limited to, historical emissions data, historical process information, and historical operational information. A written approval from the Executive Officer shall be obtained before the FSR may be modified outside ofthe 150 to 200 percent of the concentration limit. (iii) For air contaminant monitors, a multiple-span-range may be required to satisfy the provisions of Sections C(i) and (ii) above in situations where the normal concentration of the air contaminant emitted is significantly less than the allowable concentration limit. The CEMS shall have the capability to automatically change from

### RULE 218.1 (Cont.) (Adopted May 14,199)

one range to the other as appropriate to the monitor's measured concentration. (iv) For diluent monitors, the FSR shall be set such that the full range of oxygen and carbon dioxide concentrations can be measured. The FSR shall be set at 25.0 percent 

### 0, (maximum) and 1.0 percent CO, (minimum) concentrations, or at a value approved by the Executive Oficer. (v) Should any data pointsfall below 10 percent of the FSR, those data points shallbe reported according the following, as applicable: (I)For CEMS with certified multiple span ranges, the owner shall report data that falls below 10.0 percent of the higher FSR and above 95 percent of the lower FSR, at the 10.0 percent value ofthe higher FSR, 

### (11) In the eventthat any of the data points gathered by the CEMS fall below 10.0 percent of the FSR, the owner or operator may electtoreport the contaminant concentrationsat the 10.0 percent FSRvalue, or, (111) In the event that any data points gathered fall below 10.0 percent ofthe lowest vendor guaranteed FSR for that CEMS (defined as the lowest FSR that the vendor guaranteesto be capable of meeting all current certification requirements of Rule 21

### 8 and Rule 218.1, as applicable) the owner or operatormay elect to use the followingto measure and report contaminant concentrations: (a) Report data at 10.0 percent FSR value, or, (b) Report data at actual measured value, provided that the CEMS meets the Supplemental and Alternative PerformanceRequirements in AttachmentA. (vi) Should any data points fall above 95 percent. of FSR, the value shall be invalid for quantification and the CEMS shall be considered unavailable for the purposes of determining CEMS availability percentage. All excursions above 95 percent of FSR and the duration of these excursions shall be reported in the CEMS summary report asprescribed under Rule 2 18(f). Strip Chart Recorder

### RULE 218.1 (Cont.) (Adopted May 14,199)

(i) For CEMS where the strip chart recorder is used as the only means of data recording, the strip chart shall have a minimum width of at least 10inches, a readability of 0.5% of the span, and a minimum of 100chartdivisions. (ii) For CEMS where the strip chart recorder is used as a back-up system or for recording data from only a singleparameter, a strip chart of lesser sizethan specified in Section (D)(i) above, may be proposed in the application. (iii) For CEMS equipped with multiple-span ranges, the chart recorder shall have the capability to automatically change span,
as appropriate. Data Acquisition System (DAS) (i) The DAS shall maintain all recorded data in accordance with Rule 218, Section (e). (ii) For CEMS,DAS shall acquire data from monitoredparameters at least once every minute. (iii) For SCEMS, DAS shall acquire data from monitored parameters at least once every 15minutes. (iv) DAS acquisitionrate shall be set at a constant rate such that the data points areequally spaced. (v) All valid data points shall be used to determine compliancewith applicable limit(s), and, for certification testing and RATA(s). (vi) DAS sample acquisition rate during certification and RATA(s) shall be the same as the DAS sample acquisition rate during normal CEMS,or SCEMS, operation. (F) Operational Period The operational period before any certification tests shall be a minimum of 168continuoushours. (2) Certification Requirements and Performance Specifications for New or Modified CEMS Rule 218(c)(l)provides that a series of certification tests shallbe performedto demonstrate the acceptability of CEMS performance. The requirements and specifications in conductinginitial certification tests follow: (A) Calibration Error (CE)Testing

### RULE 218.1 (Cont.) (Adopted May 14,199)

The 24-Hour CE test shall be performed at the low and high ranges, namely 

### 0 to 20 and 80 to 100 percent of FSR, respectively. CE specifications shall be lessthan or equalto: (i) 2.5 percent ofthe FSR for all analyzers, and (ii) 3.0 percent of the FRS ofthe analyzer, for flow monitors, when an electronic calibrationcheckis applicable. The 24-hour CE test shall be performed once each day as close to 24- hour intervals 

### as practicable, with a total of eight (8) consecutive tests performed. The CE specifications shall not be exceeded on any of the
tests during the entiretestingperiod. (B) Analyzer Enclosure (i) The analyzer shallbe contained in an environmentally controlled enclosure. An alarm and recording device shall be incorporated into the system to alert the operator to make corrective action should the analyzer exceed the manufacturer's recommended specifications fortemperature drift. (ii) Alternatively,the owner or operator ofthe CEMS may choose to perform the 2-hour CE tests in-lieu of meeting the analyzer enclosure requirement in Section(b)(2)(B)(i).The 2-hour CE test shall be performed once every two hours 

### as close to 2-hour intervals as practicable, with total of thirteen consecutive tests performed. The 2-hr CE test shall be performed when ambient temperature is expected to vary diurnally at least 30°F. The test shall be performed at the low and high ranges of FSR, namely 0 to 20 and 80 to 100 percent, respectively. The specifications in Sections (b)(2)(A)(i)and (ii) shall apply to 2-hour CE. (iii) The owner or operator of the CEMS may qualify for an exemption fiom Section(b)(2)(B)(i) to provide environmental controls for.the analyzer enclosure by demonstrating, to the satisfactionofthe Executive Officer,that the CEMS is located: 

### (I) In a geographic area where seasonal high and low temperatures do not exceed the operational temperature specificationsforthe analyzer, (11) In a geographic area where monthly maximum temperature variation is less than 30°F for all months ofthe year, and

### RULE 218.1 (Cont.) (Adopted May 14,199)

(111) The CEMS is located in a site that is protected from radiationand convectionheating sources. RelativeAccuracy RATA shall be performed for raw contaminant concentration, and if applicable, for corrected concentration, emission rate, 02concentration, C02 concentration analyzers, and stack and fuel flow monitors. There shall be a minimum of nine sets oftest data generated. If the number of tests exceeds nine sets, data may be discarded if it is identified as an outliers by the technical guidance set forth by the Executive Officer, or for valid reasons (e.g., process upsets, CEMS malfunction, etc.) which
must be substantiated with appropriate documentation and subject to approval by the Executive Officer. All data collected shall be submitted to the Executive Officer.

The CEMS shallmeet the followingRAperformance specifications: (i) Less than or equal to 20.0 percent of the mean value of the reference method for pollutant concentrations, or the de-minimus concentrationas follows, whichever is greater: Pollutant De minimus Concentration

NOx 1.0ppm 

## so2 2.0 ppm CO 2.0ppm Reduced SulfurCompounds 4.0 ppm (ii) Less than or equal to 10.0 percent of the mean value of the reference method for diluent concentrations, or the de minimus value of 1.0 percent 

### 02, whichever is greater. (iii) Less than or equal to 15.0 percent of the mean value of the reference method for flow monitors, or the de minimus value equivalent to a calculated volumetric flow rate based on 2 feet per second stack gas velocity for cases where the mean stack gas velocity obtained by the reference method test is less than 15 feet per second. (iv) Less than or equal to 20.0 percent of the mean value of the reference method for mass emission rates, or the de minimus value equivalent to a calculated mass emission rate based on 2 feet per second stack gas velocity for cases where the mean stack gas

### RULE 218.1 (Cont.) (Adopted May 14,199)

velocity obtained by the reference method test is less than 15 feet per second. The relative accuracy requirement may be met if the average of the differences between the CEMS measured data and the reference method test data plus the confidence coefficient is less than or equal to the relative accuracy de minimusvalue. (3) RelativeAccuracy Test Requirements for New orModified CEMS Within fourteen days of, or during all relative accuracy tests, the CEMS shall meet the following requirements,except those that may be waived as allowed in Rule 2 18.1, Section(b)(4)(C): (A) Response Time The response time for CO CEMS shall not exceed 1.5 minutes except where there is a technical limitation, in which case the response time shall be 5 minutes. The response time for all other CEMS and flow monitors, as applicable, shallnot exceed 5minutes. 

### (B) CalibrationError The CE testing requirementsare specifiedin Section (b)(2)(A). (C) Concentration Stratification (i) The owner or operator shall demonstrate the absence of stratificationthrough testing performed according to the method in Chapter

### X, Section 13

### - "Non-Standard Methods and Techniques", of the District Source Testing Manual. The number of tests shall be determined as follows: (I) Test(s) shall be conducted at one load level if the owner or operator demonstrates to the satisfaction of the Executive Officer that the equipmentoperates within a 20 percent load range for at least 80percent of the time; (11) Test(s) shall be conducted at two different load levels if the owner or operator demonstrates to the satisfaction of the Executive Officer that the equipment operates within a 50 percent load range for at least 80percent ofthe time; or, (111) Test(s) shall be conducted atthree different load levels if the equipment operates outside of the criteria in Sections (b)(1 )(C)(i)(I) and (11). The absence of stratificationis considered verified ifthe difference between the highest measured concentration (time normalized) and

### RULE 218.1 (Cont.) (Adopted May 14,199)

(ii) the lowest measured concentration (time normalized) divided by the 'average measured concentration (time normalized), when expressed as apercentage, is less than or equalto 10 percent. Upon verification of the absence of stratification, the owner or operator may position the CEMS sampling probe at any point within the stack with the exception of those points that are adjacent to the stack wall. The CEMS sampling probe should be located in the stack at least one-third of the stack diameter. The 

### RM for 

### RATA may be conducted at a single point within the stack that is not adjacentto the stack wall and does not interfere with the sampling and the operation of the facility CEMS.

Should testing demonstrate the presence of stratification, the

owner oroperatormay elect one ofthe following alternatives: 

### (I) If the stratification is greater than 10 percent but the differencebetween the highest measured concentration (time normalized) and the lowest measured concentration (time normalized) is less than or equalto 1.0ppmv: (a) Then the CEMS sampling probe may be located at any point within the stack exceptanypoints that is adjacent to the stack or adjacent to the highest measured concentration (time normalized) and the lowest measuredconcentration (time normalized), or (b) If it is not possible to avoid using a point adjacent to either the highest measured concentration (time normalized) or the lowest measured concentration (time normalized), then locate the CEMS sampling probe suchthat theplacement minimizesthe difference between the concentration at the proposed probe location and the concentration at the point of highest measured concentration (time normalized) or the lowest measured concentration (timenormalized). (11) Determine a representative CEMSprobe location such that the following criteriaare met: (a) all traverse point concentrations are within 10.0% of the average of all traverse point concentrations (time

### RULE 218.1 (Cont.) (Adopted May 14,199)

normalized), or, the difference is less than or equal to 1.0ppm, whichever is greater, and (b) there exists at least one traverse point concentration (Xr), not located next to the stack or duct wall, that is less than or equal to 10.0% each adjacent traverse point concentration of

### Xr, or the differenceis less than

or equal to 1.0ppm, whicheveris greater, and, (c) the CEMS probe is located at (or as near as practical) Xr with minimum adjacent traverse point concentration fluctuations as determined in section (ii)(II)(b),above. (111) Determine a representative multiple point sampling configuration as approved by the Executive Officer, following the guidance document by EmissionMeasurement Technical Information Center, "Evaluation Procedure for Multi-Hole Sample Probes" (EMTIC GD-031) (IV) Modify the stack andlor CEMS samplingprobe location and
retest for the absenceof stratification. (D) Cyclonic Flow The owner or operator shall perform tests to verify the absence of cyclonic flow for the CEMS and reference method sampling probes. The cyclonic flow test shall be required when measuring mass emission
rates and shall be performed according to the District method in the SourceTest Manual, Chapter

### X: Non-Standard Methods and Techniques following the testing conditions of Section (3)(C)(i)(I), (11) or (111), as applicable. (E) Interference The owner or operator shall perform tests to verify the absence of sampling, analyticaland flowinterference, as applicable. (F) Linearity Error LE tests shall be performed at the low, middle and high ranges of concentration,namely 20 to 30, 50 to 60, and 80 to 100 percent. Each calibration gas shall be introduced intothe CEMS three times. The same gas shall not be used twice in succession. LE shall be less than or equal to 5.0 percent of the calibration gasconcentration. (G) Multiple -Span-Range

### RULE 218.1 (Cont.) (Adopted May 14,199)

For CEMS that have multiple- span range, all certification tests shall be performed at the lowest range. Except for 

### R4 and interference tests, all other certification tests shall be performed on other ranges. Operational Requirements and Performance Specifications for New or Modified CEMS After final approval, the CEMS shallbe subsequently operated and maintained according to the following requirements and specifications: (A) 24-HowCE CE tests shall be performed once each day as close to 24 hour intervals



### as practicable at the low (0 to 20 percent) and high (80 to 100 percent) ranges of concentration. CE test results which are greater than the limits specified in Sections (b)(2)(A)(i) and (ii), but less than or equal to 5.0 percent of the full span range shall be addressed by QNQC Plan remediation. The CEMS shall be deemed out-of-control during such period when any CE test result is greater than the specified limits and greater than 5.0percent ofthe full span range, until the CE test meets the specifications. All data generated by the CEMS during an out-of-control period shall be deemed invalid but shall not be deleted or excluded from the records or database. 

### (B) System Bias Test A system bias shall be conducted every 12 months in conjunction with relative accuracy audit required under Rule 2 18 Section (b)(4)(C). The CEMS system bias shall not exceed

# + 5.0 percent of the full span range for contaminant analyzers. In addition, the owner or operator shall include in the facility QNQC Plan, criteria for excessive drift (e.g. control limits on cumulative drift) and appropriate diagnostic techniques
to identify sources of analyzer drift and system bias when control limits

are exceeded. (C) Relative Accuracy Testing UTAand RAA, as applicable, shall be performed at least once every 12months. The test shall be completed annually no later than the end of the calendar quarter in which the date of the original certification test was performed. During any relative accuracy tests after CEMS certification, the owner or operator may request a waiver from stratification, cyclonic flow, andlorinterference requirements in Sections (b)(3)(C), (D) and (E), respectively, by submitting to the Executive

### RULE 218.1 (Cont.) (Adopted May 14,199)

Officer, for approval, any applicable documentation or previous test or historical data that meets the stratification, cyclonic flow, andlor interferencerequirements. (D) Cylinder Gas Audit (CGA) A CGA shall be performed every calendar quarter but in no more than three quarters in succession. The CGA shall be conducted according to the provisions of 40 CFR 60, Appendix F. The audit gases shall be accordingto the certificationrequirements'of Rule 218.1. (E) The Executive Officer may require recertification of the CEMS if the annual availability percentage is below 

### 95 percent. Annual CEMS availability percentage calculations will be based on the year ending on the last day of the calendar quarter in which the CEMS was originally certified. 

### (F) The owner or operator of a CEMS that requires moisture correction in reporting flow and concentration shall measure and monitor moisture in the stack gas used for emission data calculations in accordance with the written technical guidance document set forth by the Executive Officer. Alternatively, with Executive Officer approval, for equipment whose moisture source is only from fuel combustion, the operator may calculate the moisture content using fuel properties and ambient air humidity data or, for processes that saturate the exhaust gas with moisture, such as a wet scrubber system, the operator may use the saturationtemperaturefor moisture content data.

(c) Standards for Existing CEMS In order to be a Certified CEMS, a CEMS subjectto theprovisions of Rule 218 Sections (d)(l)and (d)(2), shallmeet the following operational requirements and performance specifications,andthe standardsofRule 2 18.1 Section (d): (1) Performance Specifications for Existing Gaseous Air Contaminant CEMS Parameter Specifications (A) Operational Period Greater than or equal to 168 hours 

### (B) Calibration Error Less than or equal to 

### 5 percent of the calibration gas value (C) Response Time Less than or equalto 10 minutes (D) Zero Drift (2-hour) Less than or equal to 2 percent of FSR (E) Zero Drift (24-hour) Lessthan or equal to 2 percent ofFSR-- 

### RULE218.1 (Cont.) (Adopted May 14,199)

(F) Calibration Drift (2-hour) Less than or equal to 2 percent ofFSR (G) Calibration Drift (24-hour) Less than or equalto 2.5 percent ofFSR. 

### (H) RelativeAccuracy Less than or equal to 20 percent of the mean value of the 

### RM test data, or, less than or equal to 10 percent of the allowed concentration, whicheveris greater (2) Performance Specificationskhi&m+for Existing Diluent Gas CEMS Parameter Specifications (A) Operational Period Greaterthan or equal to 168 hours (B) Calibration Error Less than or equal to 5 percent of the calibration gasvalue (C) Response Time Lessthan or equalto 10 minutes (D) Zero Drift (2-hour) Less than or equalto 0.4 percent C02or 02 

### (E) Zero Drift (24-hour) Less than or equalto 0.5percent C02or 02 (F) Calibration Drift (2-hour) Less 

### thanor equal to 0.4 percent C02or 02 (G) Calibration Drift (24 hour) Lessthan or equal to 0.5 percent C02or 02 

### (3) Full Span Range forExisting CEMS The instrument FSR shall be equivalent to approximately 200 percent of the concentration limit as specifiedin the applicablerule, or at a value approved by the Executive Officer. Oxygen and carbon dioxide instrument full span readings shall be such that the fill range of concentrations encountered can be measured. (4) Cycle of Operation for ExistingCEMS The CEMS shall complete a minimum of one cycle of operation (sampling, analyzing and datarecording), for each successive 15 minute period.



### (d) Standards, Specifications and Requirements for New, Modified and Existing CEMS: (1) Calibration Gas (A) Calibration gas mixtures, as defined in Rule218.1 (a)(8), shall be manufactured, analyzed and certified in accordance with the "EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards"

## - EPA-600/R97/121, September 1997Revision (EPA Protocol). The certification period and recertification requirements, as applicable, shallbe according to the EPA Protocol.

### RULE218.1 (Cont.) (Adopted May 

### 14,199)



### (B) For gas calibration standards not explicitly covered by the EPA Protocol, the CEMS owner or operator shall submit the gas manufacturer's alternative certification protocol for the specific compound or compounds. 

### (i) The procedures of the EPA Protocol shall be used for gas calibration standards not explicitly covered therein, except that the gas manufacturer must identify a recertificaton period and submit data documenting the applicability of this period. The gas manufacturer may submit alternative performance standards for certification andrecertification, based on supporting technical data also provided by the manufacturer. This alternative shall be subject to the approvalofExecutive Officer. (ii) If there is no existing National Institute of Standards and Technology (NIST) standard for the measured parameter, the gas manufacturer may submit an alternative reference standard and the supporting technical data that define the stability, accuracy, and precision of the alternative reference standard. This alternative shallbe subjectto the approvalofExecutiveOfficer. (iii) The CEMS owner or operator may submit an alternativeprotocol to the EPA Protocol, provided that the CEMS owner or operator demonstrates through supporting technical data that the procedures therein are not applicable to the constituent in the calibration gas standard being certified. This alternative shall be subject to the approval ofExecutiveOfficer. (C) Compressed andor filtered air, such as instrument air, may also be used 

### in lieu of oxygen span gas provided that the CEMS owner or operator demonstrates,to the satisfactionofthe Executive Officer,that it is of equivalent quality to the calibration gas standards above. As part of such documentation,the owner or operator shall include in their QAIQC plan the process or operation in producing such compressed andorfiltered air and periodically checking that compressed air andor filtered air continuesto meet the calibrationgas standards. Zero Gas Zero gases used shall meet the following criteria: (A) For gaseous air contaminant monitors, the zero gas shall be certified by the manufacturer to contain no more than 0.1 ppm of the air

### RULE 218.1 (Cont.) (Adopted May 14,199)

contaminant analyzed by the subject monitor or 1.0 percent of the applicable standard,whicheveris less. 

### (B) For carbon monoxide monitors, the zero gas shall be certified by the manufacturer to contain less than 0.5 ppm carbon monoxide or 1.0 percent of the applicable standard, whicheveris less. (C) For carbon dioxide and oxygen monitors, the zero gas shall be certified by the manufacturer to contain less than 1.0 ppm carbon dioxide or oxygen. (D) Compressed and/or filtered 

### air, such as instrument air, may also be used in lieu of zero gas provided that the CEMS owner or operator demonstrates, to the satisfaction of the Executive Officer, that it is of equivalent quality to the above zero gas standards. As part of such documentation, the owner or operator shall include in their QAIQC plan the process or operation in producing such compressed and/or filtered air and periodically checking that compressed air and/or filtered air continuesto meet the zero gas standards. (3) Automatic Calibration Data If automatic adjustments to the monitor settings are made, conduct the calibration tests in a way that the magnitude of the adjustments can be determined and recorded. (4) F-Factors The owner or operator shall use in the CEMS calculations the Fd factors listed in40 CFR Part 60, Appendix A, Method 19, Table 19-1, as applicable. When alternative fuels are fired, the owner or operator shall submit data to develop Fd factors and obtain Executive Officer approval. (5) NO, to NO ConversionEfficiency The conversion efficiency tests shall be conducted according to the requirements of District Method 100.1. The value for the NO, gas shall be greater than or equal to the maximum expected or recorded NO, and greater than or equal to 20percent ofthe FSR. Time-SharingRequirements A time-shared CEMS for which an application is submitted after [date of adoption] shall meet all of the performance specifications as well as the following requirements: (1) All sources shall have mutually compatible range(s) of air contaminant gases at alltimes.

### RULE218.1 (Cont.) (Adopted May 14,199)



### (2) Each source shall have a data-reading period, at a minimum, equal to three times the longest response time of the system. For shared systems the response time is measured at the input or probe at each source. A demonstration of response time for each source shall be made during certificationtesting. Data are not to be collected following a switch of sample sources until a period oftime equalto oneresponsetime has passed. 

### (3) The CEMS shall be capable of performing and recording zero and span calibrations at each source, including the calibration factors and correction valuesbefore and after every automaticcalibration.

### RULE 218.1 (Cont.) (Adopted May 14,199)

Table 1 

### REFERENCE

### METHODS RULE 218.1

District Method 1.1

## - Sample and Velocity Traverses for Stationary Sources

District Method 1.2 

### - Sample and Velocity Traverses for Stationary Sources with Small Stackor Ducts

District Method 2.1 

## - Determination of Stack GasVelocity and Volumetric FlowRate (S-type Pitot tube)

District Method 2.2 

## -Direct Measurement of GasVolume through Pipes and Small Ducts

District Method 2.3 

### - Determination of GasVelocity and Volumetric Flow Rate from Small Stacksor Ducts

District Method 3.1 

### - GasAnalysis for Dry Molecular Weight and ExcessAir

District Method 4.1 

## - Determination ofMoisture Content

### in Stack Gases

r

# - District Method 6.1 

### - Determination of Sulfuric Acid and Sulfur Oxidesfrom Stationary Sources

District Method 7.1 

### - Determination of Nitrogen Oxide Emissions for Stationary Sources

District Method 100.1

### - Instrumental Analyzer Procedures for Continuous Gaseous Emission Sampling

District Method 307.91 

### - Determination of Sulfur in a Gaseous Matrix

EPA Method 

### 6

### - Determination of SulfurDioxide Emissions from Stationary Sources

EPA Method 19

### - Determination of Sulfur DioxideRemoval Efficiency and Particulate, Sulfur Dioxide and Nitrogen Oxides Emission Ratesfrom Electric Utility Steam Generator(40 CFR Part 60 Appendix A)

ASTM Method D 4294 or D 2622-82 

### - Determination of Sulfur in LiquidFuels