Investigation of Approaches for the Determination of Inorganic Chloramines inWorkplace Air

摘要

Direct reading instrument methods for determining the concentration of inorganicchloramines in the air at work sites were investigated. Infrared spectrometry allowed the detection of gaseous nitrogen-trichloride in atmospheres low in carbon-dioxide. Under comparable conditions it was not possible to identify either monochloramine or dichloramine. Under atmospheric levels of carbon-dioxide, the nitrogen-trichloride absorbance band was completely obscured by carbon-dioxide sidebands. Although detector tubes for chlorine reacted with nitrogen-trichloride, the presence of trace amounts of molecular chlorine interfered, making the use of detector tubes unworkable. Mass spectrometry with selected ion monitoring detected nitrogen-trichloride. The presence of amines did not seriously affect the mass spectral intensities of nitrogen-trichloride. Even after a 4 hour period the introduction of primary amines did not appreciably change the mass spectral intensity. The author concludes that mass spectrometry appears to be the technique to use for the analysis of nitrogen-trichloride.