Improved infra-red procedure for the evaluation of calibrating units.

Details

• Creators:
  Flores, Arthur L.
• Corporate Creators:
  John A. Volpe National Transportation Systems Center (U.S.)
• Corporate Contributors:
  United States. National Highway Traffic Safety Administration
• Subject/TRT Terms:
  Alcohol Blood Tests Alcohol Breath Tests Alcohol Chemical Tests Calibration Evaluation Gas Chromatography Infrared Analysis Law Enforcement Vapors
• Resource Type:
  Research Paper
• Geographical Coverage:
  United States
• Corporate Publisher:
  John A. Volpe National Transportation Systems Center (U.S.)
• NTL Classification:
  AGR-SAFETY AND SECURITY-SAFETY AND SECURITY ; NTL-SAFETY AND SECURITY-SAFETY AND SECURITY ; NTL-SAFETY AND SECURITY-Highway Safety
• Abstract:
  Introduction. The NHTSA Model Specifications for Calibrating Units for Breath
  
  Alcohol Testers (FR 72 34742-34748) requires that calibration units submitted for
  
  inclusion on the NHTSA Conforming Products List for such devices be evaluated using
  
  one of three alternate procedures, all of which were developed at the Volpe Center. The
  
  first uses gas chromatography and wet gas reference samples for evaluation. This
  
  procedure is no longer used because of the advent of dry gas CUs on the market. Gas
  
  chromatography is an inappropriate technique for evaluation of dry gases using wet gas
  
  reference samples. A second alternative uses gas chromatography with dry gas reference
  
  samples. The dry gas references were obtained from the National Institute for Science
  
  and Technology. A third procedure uses a non-dispersive infra-red spectrophotometry.
  
  This third procedure is the preferred one, since reference samples are prepared at the
  
  Volpe Center so that reliance on outside sources for reference samples is not necessary.
  
  This preferred procedure uses a National Patent Analytical Systems, Inc. Datamaster
  
  breath alcohol analyzer instrument to analyze samples. This device is a non-dispersive
  
  infra-red spectrophotometer designed for breath (ethyl) alcohol analysis and is listed on
  
  the NHTSA Conforming Products List for evidential breath testers. Analysis is based on
  
  the absorption of a band of infra-red radiation centered at 3.4 microns, a wavelength area
  
  that is strongly absorbed by alcohol and which at the same time is not interfered with by
  
  other possible substances found in human breath, other than acetone.
  
  
• Format:
  PDF
• Collection(s):
  Volpe Center
• Main Document Checksum:
  urn:sha256:eb1ea7307a71c4ee9c83f844dff31eb63022e5fc3a52e108de60d6644ff8d07b
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/12227/dot_12227_DS1.pdf
• File Type:
  [PDF - 84.15 KB ]