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LEADS/EMS ADVANCED CAL/SPAN INTERPRETATION

LEADS/EMS ADVANCED CAL/SPAN INTERPRETATION. Review All Of The Automated Tests That Are Conducted On Calibrations And Span Checks Develop An Understanding Of What Each Of These Tests Means Review The Tools Available To You For Troubleshooting Accomplished Through Case Studies Web Pages

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LEADS/EMS ADVANCED CAL/SPAN INTERPRETATION

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  1. LEADS/EMS ADVANCED CAL/SPAN INTERPRETATION

  2. Review All Of The Automated Tests That Are Conducted On Calibrations And Span Checks Develop An Understanding Of What Each Of These Tests Means Review The Tools Available To You For Troubleshooting Accomplished Through Case Studies Web Pages Manual Validation Zeno Operator Interface WHAT WE HOPE TO ACCOMPLISH

  3. Automatic Quality Control Are Normally Augmented By Quarterly Manual Span Source Audits Span Source Audits Evaluate The Accuracy Of The Station Calibrator Corrective Action Is Required If Audit Limits Are Exceeded If The Audit Passes, Then The Pollutant Monitor Should Be Adjusted To Agree With The M-level Concentration Produced By The Station Calibrator This Sets The Slope Of The Monitor’s Response To The Ideal If A Slope Test Warning Is Reported Thereafter, Then Action Must Be Taken To Determine If The Error Was Caused By Monitor Drift Or Span Source Drift A Span Source Audit May Be Needed If There Are No Obvious Instrument Problems SPAN SOURCE AUDITS

  4. There Are Several Types Of Quality Checks Calibration Sequences Are Run Periodically Or When Equipment Is Changed To Establish A New Slope And Intercept Span Check Sequences Are Run Weekly To Ascertain Whether Or Not A Particular Instrument Is Drifting Or Haywire - May Also Set A New Intercept Span-Zero Sequences Can Be Run Nightly To Catch Instrument Drift Any Of These Sequences Can Be Automatically Scheduled On Either The Calibrator Or The Data Logger Any Of These Sequences Can Be Manually Initiated As Necessary QUALITY CHECKS

  5. Sequences Are Composed Of Levels A Level Consists Of A Set Concentration From The Station Calibrator Introduced Into A Monitor For A Set Number Of 5-Minute Sample Periods Each Level Is Assigned A Letter Code (M, R, S, T, Or G) By The Datalogger -- These Correspond To Various Percentages Of The Instrument Full-Scale A Set Number Of 5-Minute Samples (Usually 3) In Each Level Are Allowed For Instrument Stabilization The Remaining Samples (Usually 4) Are Processed By LEADS. CALIBRATION SEQUENCES

  6. During Calibrations Completeness Monitor Voltage and Concentration Outlier Checks Concentration Spacing Check Slope/Intercept Checks Zero/Span Checks Precision/Linearity Check Converter Efficiency Checks (NOx & H2S) Scrubber Efficiency Checks (H2S) During Span Checks Completeness Monitor Voltage and Concentration Outlier Checks Concentration Spacing Check Zero/Span Checks Linearity Check Converter Efficiency Checks (NOx & H2S) Scrubber Efficiency Checks (H2S) LEADS QC CHECKS

  7. All QC Tests Performed On Calibration Or Span Check Data Have Both Warning And Failure Limits Except The Outlier Tests Each Outlier Test Uses Only One Limit But The Test Is Repeated If An Outlier Is Detected. Each Warning Limit Is Chosen Statistically To Represent The 3rd Standard Deviation Value About The Mean Error Of A Test There Should Be Only A 0.27% Probability Of Exceeding A Warning Limit If The Monitoring System Is Working Properly DO NOT IGNORE WARNINGS TEST LIMITS

  8. Each Failure Limit Is Chosen To Be At Least 1.5 Times The Warning Limit And Is Intended To Represent The Maximum Error That Will Be Tolerated Without Invalidation Of The Affected Data Ideal Values For Each Of The Tests Are Listed In The Calibration And Span Check Reports Available From The CAMS Status Report Web Pages. The Limits Can Also Be Seen On The Cal Limits Web Page For Each Test, The Ideal Value Is Subtracted From The Measured Value To Obtain The Test Error. This Error Is Then Compared To The Warning And Failure Limits. TEST LIMITS (Cont.)

  9. Automatic Invalidation Of Data Is Based Only On Whether A QC Test Passes Or Fails Warnings Are Not Considered In This Processing Failure Of A Concentration Outlier Test Or A Concentration Spacing Test Indicates A Problem With The Calibration System But Not With The Monitor (Except NO2) The Calibration Or Span Check Event Involved Is Considered Invalid And The Ambient Pollution Data Is Unaffected DATA VALIDATION RULES

  10. AUTOMATIC CALIBRATION TESTS

  11. AUTOMATIC SPAN TESTS

  12. Incomplete The Data Did Not Arrive In The Proper Sequence Or There Were Either Too Few Or Too Many Samples At Each Level Invalid The Calibrator Did Not Deliver The Challenge Gas At Correctly Spaced Intervals Failed One Or More Of The Automatic QC Checks Exceeded A Pre-Set Failure Limit -- Data Is Automatically Rejected Accordingly Warning One Or More Of The Automatic QC Checks Exceeded A Pre-Set Warning Limit -- The Calibration Or Span Check Is Still Valid And Is Still Used Passed All Automatic QC Checks Were Passed POSSIBLE QC CHECK FLAGS

  13. Level M* R S T* G* Conc. (ppm) 0.4, CO 40 0.3, CO 30 0.2, CO 20 0.09, CO 9 0.0 O3, SO2, AND CO CAL SEQUENCE * Note - Levels used during Span Checks

  14. Level G* M* M†* R R† S S† T* T†* NO Conc. (ppm) 0 0.47 0.07 0.37 0.07 0.27 0.07 0.16 0.07 NO2 Conc. (ppm) 0 0 0.4 0 0.3 0 0.2 0 0.09 NOx Conc. (ppm) 0 0.47 0.47 0.37 0.37 0.27 0.27 0.16 0.16 NO, NO2, AND NOX CAL SEQUENCE *Note - Levels used during Span Checks †Note - Gas Phase Titration Levels

  15. H2S CAL SEQUENCE Level M* R S T* T1* T2* G* H2S Conc. (ppm) 0.4 0.3 0.2 0.09 0 0 0 SO2 Conc. (ppm) 0 0 0 0 0.09 0.09 0 Scrubber Bypassed No No No No Yes No No *Note - Levels used during Span Checks T1 - H2S Converter Efficiency Check T2 - SO2 Scrubber Efficiency Check

  16. Performed On Both Calibrations And Span Checks Tests To See That Data Arrives In Correct Order And The Correct Number Of Updates For Each Level Are Present Possible Failure Modes: Data Received Out Of Order Comms Processing Problem - Can Generally Be Recovered By Reloading Data Missing Data During A Cal Or Span Power Outage - No Can Do Comms Processing Problem - Can Generally Be Recovered By Reloading Data Zeno Time Flagging - Can Generally Be Recovered By Reloading Data Too Many Update Steps For A Given Level Cals/Spans Started Without Capturing Valid Data Between Them Trip To Station Not Always Necessary COMPLETENESS TEST

  17. Performed On Both Calibrations And Span Checks Tests Are Based On The Measured Voltages From The Instrument Tests To See That No Single Voltage Measurement For A Level Is More Than An Allowed Deviation From The Average Voltage Possible Failure Modes: Low Source Air Pressure Empty Gas Bottle Zeno Incorrectly Translating Voltage In To Voltage Out Incorrect Analog Span Adjustment On Instrument Moisture In Lines You Must Go To The Station And Check The Equipment VOLTAGE OUTLIER

  18. Performed On Both Calibrations And Span Checks Tests To See That No Single Concentration Measurement For A Level Is More Than An Allowed Deviation From The Average Concentration This Test Was Specifically Designed To Catch Calibration System Problems Possible Failure Modes: Calibration System Problems Low Source Air Pressure Empty Gas Bottle Ozone Generator Problem Instrument Span Set Incorrectly Other Instrument Problem Moisture In Lines You Must Go To The Station And Check The Equipment CONCENTRATION OUTLIER

  19. Performed On Both Calibrations And Span Checks Based Entirely On NO Channel Performance On Previous Non-Titration Level (M-Level) And Current Titration Level (M*-Level) -- NO2 Voltages Are Not Part Of This Test Tests To See That No Single Concentration Measurement For A Level Is More Than An Allowed Deviation From The Average Concentration Possible Failure Modes: O3 Concentration Unstable NO Concentration Unstable Other Instrument Problem Leak In Line Moisture In Lines You Must Go To The Station And Check The Equipment NO2 CONCENTRATION OUTLIER

  20. NO2 CONCENTRATION CALCULATIONS NO Voltages And Concentrations NO2 Concentrations

  21. Performed On Both Calibrations And Span Checks Tests To See That The Calibrator Is Delivering Evenly Spaced Concentrations Throughout The Instrument’s Range No Concentration For A Level Can Be More Than An Allowed Deviation From The Ideal Concentration Possible Failure Modes: Bad Source Air Supply Generally Shows Up With T-Level Too High Bad Ozone Generator Inside Calibrator Generally Shows Up With T-Level Too Low Empty Gas Bottle Moisture In Lines You Must Go To The Station And Check The Equipment CONCENTRATION SPACING

  22. NO2 CONCENTRATION SPACING • Performed On Both Calibrations And Span Checks • Based Entirely On NO Channel Performance On Previous Non-Titration Level (M-Level) And Current Titration Level (M*-Level) -- Differs From Normal Concentration Spacing Test • No Concentration For A Level Can Be More Than An Allowed Deviation From The Ideal Concentration • Possible Failure Modes: • Calibration Of O3 Generator Does Not Agree With NO Calibration • Leak In Line • Other Instrument Problem • Moisture In Lines • You Must Go To The Station And Check The Equipment

  23. Performed Only On Calibrations Tests To See That The Instrument Is Responding Correctly. All Instrument Responses Should Be Linear And The Calculated Slope Should Be Near The Ideal Ideal Slopes: CO = 20 Other Pollutants = 1000 (0 - 1000 ppb Instrument Range) Other Pollutants = 2000 (0 - 500 ppb Instrument Range) Possible Failure Modes: Low Source Air Supply (Not If Concentration Spacing Test Passes) Empty Gas Bottle (Not If Concentration Spacing Test Passes) Span Adjustment Incorrect On Instrument Moisture In Lines Instrument Response Drift Due To Malfunction Or Wear You Must Go To The Station And Check The Equipment SLOPE

  24. Performed Only On Calibrations Tests To See That The Instrument Is Responding Correctly And That The Calculated Intercept Is Near The Ideal Ideal Intercept = 0 Possible Failure Modes: Bad Or Incorrect Instrument Zero Moisture In Lines Instrument Malfunction Or Wear You Must Go To The Station And Check The Equipment INTERCEPT

  25. Performed Only On Calibrations Tests To See That The Instrument Has A Stable, Linear Response The Voltage Average For Each Level Is Compared To The Calculated Regression Line And Must Be Within Limits Possible Failure Modes: Instrument Out Of Whack - Order More Whack Moisture In Lines Calibrator Not Delivering Stated Concentration You Must Go To The Station And Check The Equipment PRECISION

  26. Performed Only On Spans Tests To See That The Instrument Is Holding A Stable, Linear Response The Voltage Average For The T-Level Is Compared To The Line Drawn Between The M-Level And The G-Level And Must Be Within Limits Possible Failure Modes: Instrument Out Of Whack - Order More Whack Moisture In Lines Calibrator Problem You Must Go To The Station And Check The Equipment LINEARITY

  27. Performed On Both Calibrations And Spans Tests To See That The Instrument Calibration Is Holding Since The Last Good Calibration Or Span The Voltage Average For The G-Level Is Compared To The G-Level From The Last Good Calibration Or Span And Must Be Within Limits Possible Failure Modes: Low Source Air Supply Gas Bottle Concentration Wrong Instrument Zero Off Moisture In Lines You Must Go To The Station And Check The Equipment ZERO

  28. Performed On Both Calibrations And Spans Tests To See That The Instrument Calibration Is Holding Since The Last Good Calibration Or Span The Voltage Average For The M-Level Is Compared To The M-Level From The Last Good Calibration Or Span And Must Be Within Limits Possible Failure Modes: Low Source Air Supply (Not If The Spacing Test Passes) Empty Gas Bottle (Not If The Spacing Test Passes) Incorrect Instrument Span Moisture In Lines You Must Go To The Station And Check The Equipment SPAN

  29. Performed On Both Calibrations And Spans Tests The Electronic And Flow Balance Between The NO and NOx Channels. Compares The Ratio Of The Average NO2 Span Response To The Average NO Span Response During Non-Titration Steps. Sensitive To NO2 Impurities In NO Cylinder. Impurities Give Positive Errors. Only Affects The Validity Of The NO2 Channel Calibration You Must Go To The Station And Check The Equipment NOx BALANCE TEST Numbers Are From The NOx Calibration At CAMS 12 on July 28, 1998 MNO2 - GNO2 MNO - GNO

  30. Performed On Both Calibrations And Spans Tests The Efficiency Of the NO2  NO Converter Affects The Validity Of The NO2 And NOx Channel Calibrations You Must Go To The Station And Check The Equipment NOx CONVERTER EFF. TEST Numbers Are From The NOx Calibration At CAMS 12 on July 28, 1998 MNO - GNO MNOX - M*NOX MNO - M*NO MNOX - GNOX

  31. Performed On Both Calibrations And Spans Tests The Efficiency Of the H2S  SO2 Converter Based On The T-Level And The T1-Level. Test Is Sensitive To Agreement Of The Calibrations Of The H2S Cylinder To The SO2 Cylinder. This Can Cause Both Negative And Positive Errors. You Must Go To The Station And Check The Equipment H2S CONVERTER EFF. TEST Numbers Are From The H2S Calibration At CAMS 54 on July 26, 1998 T - G T1 - G

  32. H2S SCRUBBER EFF. TEST • Performed On Both Calibrations And Spans • Tests The Efficiency Of the SO2 Scrubber • Based On The T1-Level And The T2-Level • You Must Go To The Station And Check The Equipment Numbers Are From The H2S Calibration At CAMS 54 on July 26, 1998 T2 - G T1 - G

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  34. Case Study #1: SO2 Cals/ Spans At CAMS 21 July 12, 15, 16, 1998 Case Study #2: Incomplete SO2 Span At CAMS 98 July 15, 1998 Case Study #3: Failed CO Span At CAMS 13 July 22, 1998 Case Study #4: Incomplete O3 Calibration at CAMS 12 July 22, 1998 Case Study #5: Failed O3 Calibration at CAMS 86 July 12, 1998 Case Study #6: Invalid NO2 Cals At CAMS 12 July 19, 20, 26, 1998 CASE STUDIES

  35. WHERE DO YOU START LOOKING? • The Overall CAMS Summary Report Is Generally The First Place That Problems Come To Light • This Report Does Not Have Enough Information To Determine Causes, Only That Problems Exist

  36. Individual CAMS Report STATUS REPORT HIERARCHY CAL Results Report The Status Reports Use A Drill-Down Technique -- The Further Down The Report Hierarchy You Go, The More Detailed The Reports Get SPAN Results Report SPAN-ZERO Results Report Overall CAMS Report High Values Report Data Loss Report CAL/SPAN Acceptance Report Level Of Report Detail

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  38. CASE STUDY #1CAL/SPAN HISTORY • Another Place To Find Problems Is The CAMS Calibration History Web Page • This Is A Quick Look At All The Cals And/Or Spans That Have Occurred • This Web Page Has More Detailed Data Than The Overall Summary Or The Individual CAMS Summary, But Not As Much As The Calibration Or Span Report Pages

  39. CASE STUDY #1INDIVIDUAL CAMS REPORT • Once We Get To Here, We Can See Which Parameter Has Problems • We Still Don’t Have Enough Detail To Determine Causes

  40. CASE STUDY #1LOTS OF FAILURES • At This Point, We Can Start Seeing What Went Wrong

  41. Unstable • Low R-Level • Poor Decay Time • Unstable T-Level • Poor Rise Time • Low M-Level • Poor Decay Time • Unstable • High G-Level CASE STUDY #1WHAT’S WRONG HERE? • Manual Validation Provides A Strong Graphical Representation Of The Data Which Makes Data Analysis Much Easier

  42. Voltage Measurements • Average Voltage • Voltage Limits CASE STUDY #1VOLTAGE OUTLIER TEST • This Tests The Stability Of The Instrument’s Response • There Are Two Steps To This Test This Point Is Rejected And A New Average Is Calculated

  43. The First Outlier Has Been Rejected And A New Average Is Calculated • New Average Voltage • Based On Three Points Rejected By First Pass CASE STUDY #1VOLTAGE OUTLIER TEST, PART 2 • This Is The Second Step This Point Doesn’t Pass Either - Outlier Test Is Failed

  44. Calculated Slope And Intercept • Actual Instrument Response • Average Voltages • Failure Limit • Warning Limit CASE STUDY #1PRECISION TEST • This Tests The Linearity Of The Instrument’s Response All Of These Points Fall Outside The Limits The Instrument Does Not Have A Linear Response

  45. Calculated Slope And Intercept • Ideal Slope • Failure Limit • Warning Limit • Average Voltages Calculated Intercept Way Out Of Limits Calculated Slope Way Out Of Limits • Intercept Limits • Ideal Intercept CASE STUDY #1SLOPE & INTERCEPT TESTS • Now We Check For Instrument Drift This Calibration Has Drifted Significantly From The Ideal

  46. CASE STUDY #1SPAN REPORT • The Failures On This Span Are Very Similar To The Failures On The Previous Calibration • We Would Expect The Graphical Data To Look Similar As Well

  47. Poor Decay Time • Unstable T-Level • Poor Rise Time • Low M-Level • Poor Decay Time • Unstable • High G-Level CASE STUDY #1THIS SPAN LOOKS SICK • No Big Surprise Here -- This Looks Very Similar To The Previous Calibration

  48. The Operator Went To The Station And Found The Temperature Low And Condensation Present In The Lines CASE STUDY #1OPERATOR LOG • Based On What The Operator Found In The Station, This Was The Correct Action To Take

  49. CASE STUDY #1INTERNAL STATION TEMP • Internal Station Temp Is Monitored At All Sites • Nominal Range Is: • 77º F To 87º F • As Paul Harvey Would Say: “And Now For The Rest Of The Story”….

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