Background

Atmospheric concentrations of petrol and compounds such as toluene are potentially explosive between a lower explosive limit (LEL c. 10 per cent) and a higher explosive limit (HEL c. 90 per cent). The dangers were shown by the Buncefield oil storage depot explosion and fire in 2007. As a result, there is a real need for a system to indicate the presence of dangerous concentrations of hydrocarbon vapour.

The technology

A prototype technology which has been proven to be highly sensitive to concentrations of hexane, heptane, hexane and octane together has been developed. It is based on quartz crystal resonance - specialised coatings on quartz crystals absorb molecules of the explosive vapour, resulting in an increase in mass and correlating change in the resonant frequency. No patent applications have yet been filed.

Benefits

The QCM sensor is able to detect the presence of explosive concentrations of volatiles in less than a minute. The technique is simple and potentially a low cost device could be manufactured, which could be applied in a very simple way, like a smoke detector with a visual or audible alarm, or alternatively, incorporated into a more sophisticated system.

Development stage

The technology has been extensively tested in the laboratory and is ready to be upscaled, and a development partner is sought for this.

Lead researcher(s)

Dr Alexei Nabok