testing of new ozone photometers
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Testing of New Ozone Photometers. Ozone Transport Commission/MANEVU Fall Meeting November 14, 2013 Washington, DC Will Ollison. Testing of New O3 Photometers. Do we know what the O 3 monitor’s really measuring? - PowerPoint PPT PresentationTRANSCRIPT
Testing of New Ozone Photometers
Ozone Transport Commission/MANEVU
Fall Meeting November 14, 2013
Washington, DC
Will Ollison
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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Testing of New O3 Photometers
Do we know what the O3 monitor’s really measuring?•EPA currently certifies FEM photometers with up to 60 ppb interference bias, 24-hour zero/span drifts of 20 ppb, LODs of 10 ppb, and noise levels of 5 ppb but notes in the 2013 ISA (EPA 600/R-10/076F) that these criteria “…should be revised to more accurately reflect the necessary performance requirements for O3 monitors used to support the current NAAQS”.
•NIST staff notes (Norris et al. 2013 JAWMA 63: 565-574) that “…regular audits currently provide reliable measures of field monitor precision and bias in response to challenges of O3 in zero air, although not of sample matrix effects arising from ambient humidity and interfering species (Spicer et al. 2010 JAWMA 60: 1353-1364)”.
•New monitor testing suggests actual NAAQS attainment is better than reported and affordable photometer scrubber upgrades will improve O3 measurement accuracy Ollison et al. 2013 JAWMA 63: 855-863; Johnson et al. 2013 JAWMA (in press).
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Ozone Monitor Types
EPA is currently evaluating the NO-scrubbed 2B Technologies 211 photometer and the Teledyne-API 265E NO-O3 chemiluminescence monitor as potential new ozone Federal Reference Methods
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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Percent O3 Monitor Share U.S. Network (1990-2011)
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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TE49C-211 Hourly Difference & Collocated NO & VOCs
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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Ollison et al. (2013) JAWMA 63: 855-863.
211 ME Factor (211F) & 205-211 Difference (205D) Home Activity
Johnson et al. (2013) JAWMA (in press)
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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GPT Scrubberless Module™
Drop-in NO-scrubbers are commercially available from 2B Technologies to convert Teledyne-API & Thermo photometers to “interference-free” (H2O, Hg, aromatic VOCs) O3 monitors.
1220 L Street, NW • Washington, DC 20005-4070 • www.api.org
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