Abstract: There is provided an emission testing system which maintains system integrity and which can be manufactured at less cost than current standard emission testing systems. The system includes a sampling unit for collecting emissions from a vehicle and diluting the collected emissions with background ambient air as required and means for drawing a proportional test sample from the bulk air/emission mixture. The analyzer is a single unit which includes a reaction cell for chemiluminescence reactions and a combustion cell for flame ionization analysis. In addition the system includes a common sample conditioning for the test sample prior to splitting the test sample for chemiluminescence and flame ionization analysis.

Abstract: An improved catalytic reactor system and method for removing interferents such as reactive hydrocarbons from the gas being sampled by gas component determination apparatus is disclosed. The sample from which the interferents are to be removed is blended with ozonized air and saturated to at least 15% with water vapor. The mixture is then passed through the catalytic reactor which, preferably, contains a mixture of platinum oxide mixed with sand and maintained at an operating temperature of 200.degree. to 280.degree. C. Additional catalytic mixtures which may be employed in the reactor are also disclosed. Methods of preventing the poisoning of catalytic reactors and rejuvenating poisoned catalytic reactors are also disclosed.

Abstract: A method of measuring trace level hydrogen chloride concentration in a gas stream is disclosed. The gas stream containing hydrogen chloride is passed through a heated vitreous carbon catalyst and then mixed with ozone in a point source reaction chamber. The light emitted in the chemical reaction is measured by a sensitive amplifier and the output is displayed on a meter, recorder, or any other suitable device. Apparatus for measuring trace level hydrogen chloride concentration in a gas stream is also disclosed.

Abstract: Method and apparatus for improved detection of sulfur dioxide by fluorescence are disclosed wherein the effects of interferent hydrocarbons in the test sample are eliminated. In apparatus detecting sulfur dioxide by detecting the fluorescence of sulfur dioxide from narrow band ultraviolet radiation by photomultiplier means, the test sample being fed to the fluorescence chamber is first passed through a reactor to oxidize the hydrocarbons from the sample. The effect of this oxidization is to convert interfering hydrocarbon components in the sample gas into non-interfering materials. In one embodiment employing ozone, moisture removal apparatus is added prior to the oxidization reaction to prevent the error producing formation of H.sub.2 SO.sub.4.

Abstract: A reactor for removing contaminants such as reactive hydrocarbons from the gas being sampled by gas component determination apparatus is disclosed. A confined path is disposed adjacent a high purity quartz lamp capable of generating low order wavelengths. By selecting the flow rate of the sample gas past the quartz lamp in the presence of ozone, all hydrocarbons can be photo-oxidized or all hydrocarbons with the exception of methane. Apparatus is also disclosed employing the reactor wherein the methane content of a sample gas can be determined. The sample gas is alternately measured as to the quantity of all hydrocarbons contained therein and then measured for methane. The difference between the two readings is indicative of the amount of non-methane hydrocarbons present.

Abstract: An electrochemical detection cell particularly suited for portable applications because of its small size and low cost. An enclosure is provided having two membrane surfaces. Electrodes are suspended internally between the two membranes supported by an electrochemically inert hydrophilic material containing an electrolyte solution. An improved electrode structure for use within the cell is disclosed.