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Dräger-Tubes & CMS-Handbook

Dräger sampling tubes and systems - 20351 The printed scale allows a direct reading of the concentration. Thus, calibration by the user is not necessary. Of course the length-of-stain discoloration does not correspond to the concentration as a direct measure but is, strictly speaking, a measure of the mass reaction of the air contaminant with the Dräger-Tube preparation. Since the information that 25 mg of nitrogen dioxide has reacted is not practical information for the workplace, the calibration scale is prepared in the engineering units ppm or volume percent.For many years, only a few gases could be measured with detector tubes.The main area of application was and still is the measurement of air contaminants in the workplace, in the concentration range of the occupational exposure limits. Decreasing occupational exposure limits have made it necessary to develop more sensitive Dräger-Tubes. In addition, efforts to better understand the exposure profile in the workplace have resulted in special Dräger-Tubes for long-term measurement which determine time weighted averages over given time periods.Dräger-Tubes can be schematically classified utilizing the following criteria:

ST-139-2001 Dräger-Tube Nitrogen Dioxide 0.5/c Gas measuring with Dräger-Tubes Technical gas analysis Air investigation in the workplace Compressed air for breathing apparatus Short-term tubes Long-term systems Direct indication Indirectindication Direct indication Indirectindication Length-of-stain indication Color comparison Length-of-stain indication