Guideline for the preparation and analysis of gaseous reference materials of indoor air pollutants

News

Guideline for the preparation and analysis of gaseous reference materials of indoor air pollutants

In industrialised countries more than 80% of the time is spent indoors. Products, such as building materials and furniture, emit volatile organic compounds (VOCs), which are therefore ubiquitous in indoor air. Different VOC combinations may, under certain environmental and occupational conditions, result in reported sensory irritation and health complaints. A healthy indoor environment can be achieved by controlling the sources and by eliminating or limiting the release of harmful substances into the air. One way is to use materials proven to be low emitting.

A worldwide network of professional commercial and non-commercial laboratories performing emission tests for the evaluation of products for interior use has been established. Therefore, comparability and metrological traceability of test results must be ensured. The proficiency of a laboratory can be proven by internal and external validation measures that both include the application of suitable reference materials. The emission test chamber procedure according to EN 16516 comprises several steps from sample preparation to sampling of test chamber air and chromatographic analysis. Quality assurance and quality control (QA/QC) must therefore be ensured.

To bridge the gap between QA/QC requirements and suitable reference products, the project ‘Metrology for the determination of emissions of dangerous substances from building materials into indoor air’ (20NRM04 MetrIAQ) was set up. The project is part of the European Metrology Programme for Innovation and Research (EMPIR) and aims to develop 1) gaseous primary reference materials (gPRM) and certification of gaseous (certified) reference materials (gCRM) and 2) emission reference materials (ERM).

In the project VSL and the Vlaamse Instelling voor Technologisch Onderzoek N.V. (VITO) developed gPRMs and gCRMs. Based on the development a guideline was written describing the production, sampling, analysis, handling, storage and stability and uncertainty of gPRM and gCRM relevant for indoor air pollutants. The gPRM and gCRM described are gas-phase standards containing trace levels of VOCs in nitrogen or air. The selected VOCs (n-hexane, methyl isobutyl ketone, toluene, butyl acetate, cyclohexanone, o-xylene, phenol, 1,3,5-trimethylbenzene) are chosen based on the check standard described by EN 16516. The target expanded uncertainty is 5 % for the VOCs in the gPRM and gCRM. The gPRM and gCRM can be sampled into sorbent tubes to obtain gCRM for quality assurance and quality control. Static and dynamic gPRMs and gCRMs in sorbent tubes have been developed by VSL and VITO.

Are you interested to find out how these reference materials are developed and how you can use them to improve your QA/QC?
Download the guideline here.