Ozone Lab Report

1064 Words5 Pages
2.4 Ozone (O3) Measurement Method 2.4.1 Introduction The equipment that utilizes ultra-violet light or causes ionization of air including photocopiers, laser printers, and computers can be the sources of Ozone and it can also result from outdoor traffic, besides, some air cleaners will release ozone either. Ozone is highly reactive and could cause some serious health problems to the lung if exposed to a high concentration. It may also irritate the eyes and respiratory tract. Indoor exposures to both ozone and its byproducts from ozone reactions with surfaces and other compounds found indoors can also be an underlying risk for health. Thus, it is crucial to measure the concentration level of ozone precisely. 2.4.2 Previous measurement method…show more content…
The only significant interference against O3 is suppressed using a scrubber, in which O3 is quantitatively sampled by the selective reaction with the blue Indigo dye in a stripping coil while NO2 is almost unaffected. This blue Indigo dye method is being considered for the continuous quantification of O3 in the gas phase by using the LOPAP instrument. Here a relatively new measurement way is proposed that a two-channel instrument designed to characterize and optimize the instrument’s performance (S. Peters et al., 2013). (1) Schematic setup of O3-LOPAP instrument The O3-LOPAP instrument is composed of two individual units. (i) The external sampling unit which is directly situated at the sampling site. (ii) The detection unit (19’’ instrument) in which the Indigo absorption is quantified by long path absorption in a liquid core wave guide. A temperature controlled sampling line connects both units. The schematic setup of the O3-LOPAP instrument is shown in figure 2.16. Figure 2.16 Schematic setup of the O3-LOPAP instrument (2) Working principle of O3-LOPAP…show more content…
The instrument shows a linear response with a measurement range from the detection limit (0.4 ppbv) up to 200 ppbv for a time resolution of 6 min, which is more sensitive than the previous in-situ instruments using the UV-absorption. The instrument is intended as an extension of a recently developed NO2-LOPAP instrument, for which the quantitative sampling of O3 is of importance to suppress the O3 interference. Except for NO2, all other tested interferences could be neglected. In the future, one channel ozone scrubber from the NO2-LOPAP instrument may be used for the sensitive and selective quantification of O3 and NO2 in the atmosphere. The 2.5% NO2 interference, which is only important under laboratory conditions, will be easily correctable. Reference i) Kleindienst, T.E., Hudgnes, E.E., Smith, D.F., McElroy, F.F., Bufalini, J.J., 1993. Comparison of chemiluminescence and ultraviolet ozone monitor responses in the presence of humidity and photochemical pollutants. Journal of the Air and Waste Management Association 43,

More about Ozone Lab Report

Open Document