Patent ID: 8653453

Claim:
An analysis device, comprising: a sample chamber for holding a gaseous sample; an analysis chamber arranged to receive sample gas from the sample chamber; a mass discriminator arranged to discriminate in the analysis chamber between ion species generated from the sample gas, the mass discriminator comprising detectors arranged to detect incident ions; and a wall separating the sample chamber from the analysis chamber, the wall comprising a rupture zone controllable to rupture and thereby release sample gas from the sample chamber into the analysis chamber, the rupture zone of the wall comprising a fusible device adapted to rupture on application of an electric current, the analysis chamber comprising an ion preparation region having spark gap electrodes for ionizing at least part of the sample gas as it flows through a gap between the spark gap electrodes, and wherein the flow rate of sample gas into the analysis chamber is controlled by an aperture of the rupture zone and the gap between the electrodes, and the mass discriminator is arranged such that a time window for discriminating between ion species is the time between rupture of the rupture zone and sample gas pressure in the analysis chamber preventing ions reaching the detectors.