Anaesthetic scavenger evaluation in the laboratory.

A method of testing scavenging devices in isolation in a test box was developed. The rate of pollution in the box was measured with varying ventilating and suction conditions which allowed a leak index to be calculated so that the efficacy of commercially available scavengers could be compared to the system without a scavenger, and to each other. The BOC scavenger tested reduced pollution but was less efficient at low suction rates. For this scavenger the suction rate should be greater than 20 litre min-1.