PMID- 28633004
OWN - NLM
STAT- MEDLINE
DCOM- 20180411
LR  - 20181202
IS  - 2162-2906 (Electronic)
IS  - 1096-2247 (Linking)
VI  - 67
IP  - 11
DP  - 2017 Nov
TI  - Field evaluations of newly available "interference-free" monitors for nitrogen 
      dioxide and ozone at near-road and conventional National Ambient Air Quality 
      Standards compliance sites.
PG  - 1240-1248
LID - 10.1080/10962247.2017.1339645 [doi]
AB  - Long-standing measurement techniques for determining ground-level ozone (O(3)) 
      and nitrogen dioxide (NO(2)) are known to be biased by interfering compounds that 
      result in overestimates of high O(3) and NO(2) ambient concentrations under 
      conducive conditions. An increasing near-ground O(3) gradient (NGOG) with 
      increasing height above ground level is also known to exist. Both the 
      interference bias and NGOG were investigated by comparing data from a 
      conventional Federal Equivalent Method (FEM) O(3) photometer and an identical 
      monitor upgraded with an "interference-free" nitric oxide O(3) scrubber that 
      alternatively sampled at 2 m and 6.2 m inlet heights above ground level (AGL). 
      Intercomparison was also made between a conventional nitrogen oxide (NO(x)) 
      chemiluminescence Federal Reference Method (FRM) monitor and a new 
      "direct-measure" NO(2) NO(x) 405 nm photometer at a near-road air quality 
      measurement site. Results indicate that the O(3) monitor with the upgraded 
      scrubber recorded lower regulatory-oriented concentrations than the deployed 
      conventional metal oxide-scrubbed monitor and that O(3) concentrations 6.2 m AGL 
      were higher than concentrations 2.0 m AGL, the nominal nose height of outdoor 
      populations. Also, a new direct-measure NO(2) photometer recorded generally lower 
      NO(2) regulatory-oriented concentrations than the conventional FRM 
      chemiluminescence monitor, reporting lower daily maximum hourly average 
      concentrations than the conventional monitor about 3 of every 5 days. 
      IMPLICATIONS: Employing bias-prone instruments for measurement of ambient ozone 
      or nitrogen dioxide from inlets at inappropriate heights above ground level may 
      result in collection of positively biased data. This paper discusses tests of new 
      regulatory instruments, recent developments in bias-free ozone and nitrogen 
      dioxide measurement technology, and the presence/extent of a near-ground O(3) 
      gradient (NGOG). Collection of unbiased monitor inlet height-appropriate data is 
      crucial for determining accurate design values and meeting National Ambient Air 
      Quality Standards.
FAU - Leston, Alan R
AU  - Leston AR
AUID- ORCID: 0000-0002-9179-7830
AD  - a AirQuality Research & Logistics, LLC , Lebanon , CT , USA.
FAU - Ollison, Will M
AU  - Ollison WM
AD  - b American Petroleum Institute , Washington , DC , USA.
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Air Waste Manag Assoc
JT  - Journal of the Air & Waste Management Association (1995)
JID - 9503111
RN  - 0 (Air Pollutants)
RN  - 0 (Nitrogen Oxides)
RN  - 66H7ZZK23N (Ozone)
RN  - S7G510RUBH (Nitrogen Dioxide)
SB  - IM
MH  - Air Pollutants/*analysis/chemistry
MH  - *Air Pollution
MH  - Environmental Monitoring/*instrumentation/methods
MH  - Luminescence
MH  - Nitrogen Dioxide/*analysis/chemistry
MH  - Nitrogen Oxides/analysis/chemistry
MH  - Ozone/*analysis/chemistry
MH  - Photometry
EDAT- 2017/06/21 06:00
MHDA- 2018/04/12 06:00
CRDT- 2017/06/21 06:00
PHST- 2017/06/21 06:00 [pubmed]
PHST- 2018/04/12 06:00 [medline]
PHST- 2017/06/21 06:00 [entrez]
AID - 10.1080/10962247.2017.1339645 [doi]
PST - ppublish
SO  - J Air Waste Manag Assoc. 2017 Nov;67(11):1240-1248. doi: 
      10.1080/10962247.2017.1339645.