DIN ISO 16000-14:2012-03

This part of ISO 16000 specifies extraction, clean-up, and analysis procedures for the determination of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) collected from indoor air on particle filters backed by polyurethane foam (PUF). The method incorporates specific analyses by high resolution gas chromatography combined with high resolution mass spectrometry (HRGC/HRMS). It provides accurate quantitative data for tetra- to decachlorobiphenyls and tetra- to octachlorodibenzo-p-dioxins/dibenzofurans (total concentrations for each isomeric series). It is capable of detecting 0,2 pg/m³ or lower concentrations of most PCBs and PCDFs/PCDDs with air sampling volumes up to 360 m³ or more in special cases. However, it may not be possible to detect all analytes at 0,2 pg/m³ or lower, especially at lower sampling volumes. Precision under normal conditions can be expected to be ± 25 % or better and uncertainty ± 50 % or better. After the indoor air sample has been collected on a particle filter backed by polyurethane foam (PUF) (see DIN ISO 16000-13), the filter and polyurethane foam filter are extracted and the solutions are cleaned from the interferences by column chromatography. Column chromatographic separation into PCB and PCDD/PCDF fractions is done by elution using correspondingly different polar solvents. In accordance with the task, PCBs can be additionally separated using a carbon column into a "non-ortho-fraction" (PCB 77, 81, 126, 169) and a fraction which does not contain a "non-ortho-fraction". Analysis of the individual PCB and PCDD/PCDF fractions is carried out in each case by HRGC/HRMS. Losses during conditioning are compensated by using the isotope dilution technique; for this purpose, isotope-labelled extraction and recovery standards are used which are added prior to HRGC/HRMS analysis. The method is applicable in rooms of residential buildings, office buildings and public or commercial institutions, including those with large internal open areas (for example, factories, department stores, closed stadiums). When the corresponding boundary conditions are observed, the method can also be used in small rooms, for example, children's rooms as well as offices. Sampling of PCBs and PCDDs/PCDFs is described in standard DIN ISO 16000-13 (both parts 13 and 14 together represent the complete PCB/PCDD/PCDF measurement procedure) and the sampling strategy to analyse PCBs, PCDDs/PCDFs and PAHs in indoor air is described in DIN ISO 16000-12. Several PCBs and PCDDs/PCDFs are considered to be potential human carcinogens. There are 209 individual PCBs, 75 PCDDs and 135 PCDFs (congeners). The most toxic PCBs are those that are coplanar and structurally similar to PCDDs. The most toxic PCDD is 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). PCBs are emitted into indoor air primarily from concrete sealers, certain paints or electrical capacitors, all of which have been banned in recent years. The principal sources of PCDDs/PCDFs in indoor air are impurities in wood preservatives containing pentachlorophenol (PCP) and emissions from fires involving chlorinated products. Tracked-in soil and emissions from nearby landfills and abandoned industrial sites may also contribute PCBs and PCDDs/PCDFs to the indoor environment. Interested parties: supervisory authorities, testing laboratories, professional associations and planning offices as well as interior designers, building industry, paint industry, adhesives industry or other branches producing items for the interior. The International Standard has been prepared by ISO/TC 146/SC 6 "Indoor air" in Working Group 9 "Measurement of dioxins and PCB". The secretariat of SC 6 is held by DIN and it is under German chairmanship. The responsible German committee is NA 134-04-02-13 UA "Messen von Dioxinen, PCB, PBF (I)" ("Measurement of dioxins, PCBs, PBFs (I)").