Dioxin sampling – A long term view

1) Introduction

The expansion of the number of processes requiring measurement of emitted dioxins and the release of a new CEN Standard - EN 1948 - will significantly alter the market for instrumentation. Within the EU, individual member states will implement their own strategies for process approval based on dioxin sampling. However, typically processes are assessed quarterly, biannually or annually using isokinetic sampling trains often operated by consultants. The resultant data is very often open to public criticism as the tests are infrequent, short term and may not be truly representative of the overall, annual emission rate.

This paper describes a programme for the development of a prototype variable term dioxin sampler. The instrument will give an integrated sample of emitted dioxins over extended sampling periods for subsequent analysis. The sampler is designed to operate in process environments for periods up to one month without attention and to maintain the resultant sample in a representative, undegraded condition for the sampling period. A back-up analysis cartridge is provided to act as a check on sampling integrity.

The prototype will be evaluated on-site against a standard commercial isokinetic dioxin sampler that follows a fixed methodology such as EN1948 and/or USEPA Method 23. The analysis of samples from both instruments will be conducted under afixed quality scheme by a single laboratory to ensure consistency.