Preparing to Measure the Effects of the NO_xSIP Call— Methods for Ambient Air Monitoring of NO, NO₂, NO_y, and Individual NO_zSpecies

Abstract

The capping of stationary source emissions of NO x in 22 states and the District of Columbia is federally mandated by the NO x SIP Call legislation with the intended purpose of reducing downwind O 3 concentrations. Monitors for NO, NO 2 , and the reactive oxides of nitrogen into which these two compounds are converted will record data to evaluate air quality model (AQM) predictions. Guidelines for testing these models indicate the need for semicontinuous measurements as close to real time as possible but no less frequently than once per hour. The measurement uncertainty required for AQM testing must be less than ±20% (±10% for NO 2 ) at mixing ratios of 1 ppbv and higher for NO, individual NO z component compounds, and NO y . This article is a review and discussion of different monitoring methods, some currently used in research and others used for routine monitoring. The performance of these methods is compared with the monitoring guidelines. Recommendations for advancing speciated and total NO y monitoring technology and a listing of demonstrated monitoring approaches are also presented.

Ground‐level nitrogen dioxide concentrations inferred from the satellite‐borne Ozone Monitoring Instrument

“…Because the reduction of NO 2 to NO is not specific to NO 2 and NO z species are also reduced to NO, these chemiluminescence analyzers overestimate ambient NO 2 concentration by a variable amount [Winer et al, 1974;U.S. Environmental Protection Agency, 1975;Grosjean and Harrison, 1985;Demerjian, 2000;McClenny et al, 2002;Gerboles et al, 2003;Dunlea et al, 2007;Steinbacher et al, 2007].…”

Interferences in photolytic NO<sub>2</sub> measurements: explanation for an apparent missing oxidant?

“…Catalytic conversion has been well documented to have positive responses to NO y species such as nitrous and nitric acid as well as organic nitrates (Dunlea et al, 2007;Grosjean and Harrison, 1985;Winer et al, 1974). Photolytic conversion has been demonstrated to be affected by a negative interference from the photolysis products of VOCs reacting with NO within the photolysis cell (Villena et al, 2012) and has a possible positive interference from thermal decomposition of NO y (McClenny et al, 2002). Measurements of NO and NO 2 have been made in a range of low-NO x locations using the chemiluminescence technique (Huntrieser et al, 2007;Lee et al, 2009;Peterson and Honrath, 1999;Zhang et al, 2008).…”

Technical note: Evaluation of standard ultraviolet absorption ozone monitors in a polluted urban environment

“…Possible interferences in this measurement technique have been summarized in several recent reviews (Cavanagh and Verkouteren, 2001;Demerjian, 2000;Environmental Protection Agency, 1993;McClenny et al, 2002;Parrish and Fehsenfeld, 2000;Sickles, 1992). Overall, previous evaluations of the performance of UV O 3 monitors have yielded mixed results.…”