Breath analyser

This colour change is the principle on which the breath analyser operates. Instrumental methods of breath alcohol analysis have recently been reviewed [24]. Enzymatic methods are usually based on alcohol dehydrogenase which catalyses the oxidation of ethanol to acetaldehyde ... 

OIML (1988) International Recommendations Relating to Evidential Breath Analysers. Reporting Secretariat OIML (SP 30-SR 13), Prance. 

FIGURE 11.3 Discriminant values calculated from peak patterns detected in 2D GC-IMS topographic plots of breath analyses from 36 lung cancer patients and a healthy control group of 54 subjects. (Reprinted from Bader, S. Urfer, W. Baumbach, J. I. J. Chemometrics. 2006, 20, 128-135. Copyright 2006, with permission from Wiley InterScience.)... 

Blood, urine, and breath analyses to check for alcohol use ... 

Fig. 19.5 Diagram of the infrared analyser nnit of the Lion Intoximeter 3000 breath alcohol analyser. Reprodnced by permission of Lion Laboratories Ltd, Ty Verlon Indnstrial Estate, Barry, Wales CF6 3BE, UK.

Air intakes to heating and ventilation systems, air compressors for process, instrument and breathing air, and to prime movers for gas compressors, power generation and pumps should be located as far as practical from contamination by dust, toxic and flammable materials release sources. They should not be located in electrically classified areas. If close to possible vapor releases (as confirmed by dispersion analyses( they should be fitted with toxic or combustible gas detection devices to warn of possible air intakes hazards and snutdown and isolate the incoming air ductwork and fans. 

By corollary, if we could measure accurately the ratio of 12C to 14C in a once-living sample, we could then determine roughly how long since it was last breathing. This explains why we can date a sample by analysing the residual amounts of 14C. 

Micro-Doppler analyses can also be used for people identification. In that case, it is possible to detect Doppler frequency modulation caused by heartbeats, breathing and body motion (walk, run, head turns etc.). 

The patient takes a single vital capacity breath of 02 and exhales through a N2 analyser. Dead space gas, which is pure 02, passes the analyser first, followed by a mixture of dead space and alveolar gas. When pure alveolar gas passes the analyser, a plateau is reached. At closing capacity, small airways begin to close, leading to preferential exhalation from the larger-diameter upper airways. These airways contain more N2 as they are less well ventilated, so the initial concentration of N2 within them was not diluted with 02 during the 02 breath. 

Studies have suggested that measurement of THF concentration in the urine may be a useful biological indicator of occupational exposure to THF, whereas exhaled breath and blood analyses may be less suitable. ... 

The plots of the intensities of selected characteristic bands as a function of lateral position (so-called chemical maps) provide information on the amount of the respective molecules or molecular groups in the different morphological structures (Fig. 4.2). The band at 784 cm 1 can be assigned to out-of-plane deformation vibrational modes of the nucleobases cytosine, thymine and uracil and serves as an indicator for the presence of nucleic acids. At 483 cm-1, a C-C-C deformation of carbohydrate polymers such as starch or pectin is present in some of the spectra. To study the distribution of protein compounds, we analysed characteristic signals of the amino acid phenylalanine (1002 cm 1 ring breathe) as well as of the protein amide I band (1651 cm-1) that is brought about by vibrations of the protein backbones. The maximum of the phenylalanine signal co-localizes with a maximum in protein content... 

Ethanol in air mixtures as standards for the new generation of evidential breath alcohol analysers. 

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