An investigation into the performance of a multi-sorbent sampling tube for the measurement of VVOC and VOC emissions from products used indoors

The international standard method for the determination of volatile organic compounds (VOCs) emitted from building materials and other products used in indoor environments, ISO 16000-6:2011, specifies use of the sorbent Tenax TA. This sorbent does not allow quantifiable determination of very volatile organic compounds (VVOCs), but an informative annex to the latest version of this standard, recommends the use of multi-sorbent tubes in order to extend the volatility range of the method to include more volatile compounds. There is a need to investigate the extent of the improvement possible using these multi-sorbent tubes and also to check that the performance for compounds which are normally detected on the single sorbent tube is not compromised. Screening tests of material emissions and Nalophan bags containing atmospheres of a mixture of VVOCs of interest have been applied to compare the performance of tubes containing Tenax TA with those containing a multi-sorbent tube (quartz wool/Tenax TA/Carbograph 5TD). A significant improvement was found using the multi-sorbent tube, with no breakthrough for six VVOCs up to a sample volume of at least 10 litres, compared with maximum safe sample volumes for these compounds using Tenax TA alone ranging from <200 ml to 3.5 litres. More modest improvements were identified for a further 11 compounds.