NCJ Number
184411
Date Published
July 1996
Length
2 pages
Annotation
This paper reports on an improved method for detecting hydrogen cyanide gas released from inorganic cyanide in biological material and carbon monoxide gas found in fire gases or automobile exhaust.
Abstract
First proposed in 1988, a gas phase electrochemical (GPE) method for detecting and measuring carbon monoxide, although promising, permitted analysis of only a few samples per hour and required the full-time attention of the equipment operator. The project, sponsored by the National Institute of Justice, improves the GPE method. It involves freeing a sample of either carbon monoxide or cyanide gas from the material examined and introducing the sample into a GPE detection system. Automation of the technique allows speedy analysis so that large numbers of samples can be screened in a relatively short time. Rapid turnaround time (1 minute per sample versus several hours for other approaches) makes the method ideal for the analysis of numerous samples that accident and product-tampering investigations can generate. Tests demonstrated that the method was sensitive to concentrations in the range of interest for postmortem material and was free from interference by changes in the substances analyzed. Putrefaction of samples did not cause problems for the method. The technique is applicable to a great variety of solid and semisolid materials that are incompatible with other methods. Two cases are described to illustrate the utility and effectiveness of the improved GPE technique.