The Use of Diffusive Samplers for Monitoring of Ambient Air

Diffusive monitors have been used for workplace air monitoring for many years, and in many cases have been found to be valid and cost-effective alternatives to conventional pumped or ‘active’ samplers. The state of the art of diffusive sampling is reviewed briefly, with particular reference to workplace air monitoring, and the potential for using similar or adapted devices for measuring concentrations of environmental pollutants examined. In particular; can samplers be used to measure concentration levels some three orders of magnitude lower than in the workplace; are blanks and sensitivity adequate? Is the sampling rate affected by concentration? What is the effect of ambient air movement? Are there sufficient validation data? Can diffusive samplers measure particulates? These questions are addressed generally and by reference to specific applications. Some conclusions are reached and recommendations made for future research.