Recommended methodology for measurements of PCDD and PCDF in the nordic countries

In April 1986 the Nordic Council of Ministers recommended that the Nordic countries use a specific method for measurements of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in flue gas emissions from waste combustion. The recommended protocol, which will be re-evaluated in a years time, includes the following.A one week registration period during which the plant is studied by continuous registration of a number of operating and emission parameters. The sampling period is included in this time.A sampling procedure based on a heated filter followed by a condenser, a bottle for the condensate and an adsorbent column. Before the sampling, at least two labelled PCDD are added to the filter.No specified analytical procedure. A labelled PCDF is added before the clean-up procedure and an injection standard before the final analysis. The laboratory is free to use any method that gives at least 25% recovery of the sampling standards and 50% recovery of the clean-up standard.Reporting requirements include homologue specific results for PCDD and PCDF containing four to eight chlorine atoms as well as isomer-specific results for the “dirty dozen”. The results should be compensated for incomplete recoveries and the factors used should be reported.