Evaluation of the Datex CD-101 and Godart Capnograph Mark II infra-red carbon dioxide analysers

Performance of the Datex CD-101 and Godart Capnograph Mark II infra-red carbon dioxide analysers was investigated. The Datex machine uses a solid-state infra-red detector, while the Godart instrument uses a Luft detector. Both instruments were easy to use and the small size and light weight of the Datex was an added convenience. Linearity, stability, response time and the effect of nitrous oxide were within specification in both machines except when 10% carbon dioxide was used with the Datex analyser. Linearity of the Godart instrument was considerably better than 1% full scale deflection (fsd) quoted in the specification, while the Datex analyser was within 2% fsd (4% fsd with 10% carbon dioxide).