Comparison of chemiluminescence and ultraviolet ozone monitor responses in the presence of humidity and photochemical pollutants. Interim report 1992-1993

Technical Report · Fri Jan 01 04:00:00 EST 1993

OSTI ID:7081181

Kleindienst, T E; Hudgens, E E; Smith, D F; McElroy, F F; Bufalini, J J

The effect of water vapor on ozone monitoring instruments was investigated. Five UV type and two chemiluminescence type monitors were employed in this study. The results of the study indicate that in systems containing ozone, water vapor, and zero air only, the chemiluminescence monitors show a systematically higher reading than the UV monitors. Studies were also performed with a smog chamber with simulated polluted air and varying relative humidity. Although the presence of water vapor did not appear to be a problem, a slight positive interference was observed with the UV monitors. This interference was a result of the presence of toluene and some of its photooxidation products which are removed by the ozone scrubber and absorb some of the 254 nm radiaton used to measure ozone. It is concluded that under atmospheric conditions with moderate pollution and relative humidity, both types of instruments give satisfactory measurements for ozone.

• Research Organization: ManTech Environmental Technology, Inc., Research Triangle Park, NC (United States)
• OSTI ID: 7081181
• Report Number(s): PB-94-182672/XAB; CNN: EPA-68-DO-0106
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION MONITORING
AIR POLLUTION MONITORS
COMPARATIVE EVALUATIONS
EVALUATION
MEASURING INSTRUMENTS
MONITORING
MONITORS
OZONE