In recent years certain instrument manufacturers have claimed that evidential breath alcohol analysers using dual-sensing technologies (such as a fuel cell combined with infrared) offer certain analytical advantages over devices which operate on just one such scientific principle. This paper reviews the background to such a proposal and argues that, in fact, such systems are not at all new, but very much well tried - and extensively tested. It is argued that dual-sensing instrument systems are, in reality, based more on limitations in previously conventional analytical technology, and on historical laboratory analytical methodology, rather than a modern approach to evidential breath alcohol analysis, using the lastest available technology. The latest developments in infrared technology and associated software systems for monitoring the breath alcohol expirogram mean that the whole question of dual-sensing should be re-addressed by potential Police and industrial users of such equipment, with perhaps far less attention being paid to any local historically held or commercially advanced analytical preferences. (A)
Abstract