Q: Did you hear oxygen went on a date with potassium? A: It went OK. Sorry for the bad chemistry jokes all the good ones Argon.

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2 Q: Did you hear oxygen went on a date with potassium? A: It went OK. Sorry for the bad chemistry jokes all the good ones Argon. 2

3 Infographic Following our data point... 3

4 Learning Objectives Know the types of calibrations Know when and how to calibrate an analyzer or sampler How to document calibration Focusing on Ozone and PM 2.5 We know about calibrations, but standardization for quality control is IMPORTANT! 4

5 What does it mean to calibrate? Aligning or checking the output of an instrument to a known true standard. Ensure quality of data across monitoring network. Required in Code of Federal Regulations Title 40, Part 50 5

6 Types of Calibrations AS-IS Performed initially to assess the instruments accuracy Verifies the accuracy of the recently generated data (usually back to previous calibration) Performed to determine if the instrument warrants further maintenance FINAL Performed after an instrument has been aligned to a true standard 6

7 OMG! When do I calibrate??? TO ENSURE QUALITY OF DATA, instruments must be calibrated: During initial field installation Following physical relocation After any major maintenance or repair After an instrument has drifted outside of acceptable quality control limits Bi-annually (every 6 months) 7

8 OMG! When do I calibrate??? If possible, routine instrument calibrations should be conducted in the spring and fall months. Thus instrument calibrations bracket the beginning and end of high ozone season. 8

9 How do we do these calibrations you speak of? Be performed in a consistent manner so that all network monitoring stations in all areas of the State are calibrated in a similar fashion. Done in accordance with appropriate CARB PQAO SOP and/or instrument manual. Performed by staff other then station operator INDEPENDENT! 9

10 Multipoint Calibrations Instruments are challenged at a minimum of four different gas concentrations in addition to a pre and post zero check. High calibration point at approximately 80% of full scale of instrument range. Low calibration point should meet requirements of 40 CFR Part 58 Appendix A, Section PPM 10

11 Multipoint Calibrations Cont. To meet those criteria our typical calibration points are: 0, 320, 160, 70, 50, 0 parts per billion. 11

12 Ozone Calibrations AS-IS calibrations should me made prior to making any analyzer repairs or adjustments. Ozone scrubber and solenoid valve should not be replaced without first performing an AS-IS calibration. 12

13 Get that analyzer in line! Adjust slope and intercept of analyzer to true standard. If overall percent accuracy is: + or 3% overall > 3 PPB for the low point If ozone scrubber is replaced 13

14 Ozone Calibration Graph - As Is 0.5 Instrument Response - Ozone (ppm) Station: True Ozone Concentration (ppm) Sampler Prop. # : Calibration Date: 10/01/14 Created By: Cali Brator API 400 Pollutant: Ozone 14 y = x

15 Ozone Calibration Graph - Final Instrument Response - Ozone (ppm) Station: Sampler Prop. # : Calibration Date: 10/01/14 Created By: Cali Brator y = x True Ozone Concentration (ppm) API 400 Pollutant: Ozone 15

16 FINALize Final calibration to verify adjustment. Keep record of previous slope/intercept; in case problems found with standard. 16

17 For IZS O3 Gen Cal Aligns slope/intercept of photometer to slope/intercept of ozone generator. Should be performed: Following a change or rebuild of sample pump Adjustment of flow rate Replacement of ozone lamp After conducting a final calibration 17

18 For IZS O3 Gen Cal After O3 Gen Cal, record average of next three auto IZS calibration sequences to determine new expected values for zero, precision, and span for quality control purposes. 18

19 Calibration Report Include: Analyzer and Site ID Diagnostics and correction factors of transfer standard, flow standard, and analyzer Slope and intercept Calibration points with response from transfer standard and analyzer Percent difference from true Per TSA, reports to be housed electronically on server and copy at monitoring station. 19

20 Q: Why do chemists like nitrates so much? A: They re cheaper then day rates. 20

21 Continuous Sampler (BAM) Calibrations Calibration includes verifying and calibrating of: Outside temperature sensor Internal pressure sensor Volumetric flow controller Including leak check Verify each with certified standard; BGI Delta Cal 21

22 When should I adjust??? Temperature + or 2.0 degrees Celsius from true Pressure >10 mmhg from true Flow more then + or 2% from true If leak check does not drop below 0.5 LPM, further troubleshooting needed 22

23 Calibration Report Include: Analyzer and Site ID Diagnostics and correction factors of pressure, flow, and standard Slope and intercept Calibration points with response from transfer standard and sampler Percent difference from true Per TSA, reports to be housed electronically on server and copy at monitoring station. 23

24 Are we done yet? We know the types of calibrations We know when and how to calibrate an analyzer or sampler We know how to document calibrations 24

25 Contact: Dustin Goto