An important new ASTM standard has been published: D7706-11: Standard practice for rapid screening of VOC emissions from products using micro-scale chambers.

D7706 will benefit both manufacturing industry (e.g. QC and R&D labs) and by accredited third-party test laboratories providing a fast and low-cost approach to screening chemical emissions from materials. D7706 complements existing longer-term reference test methods and is applicable to a wide range of materials including; construction products, dried or cured paints/coatings/adhesives, compressible products (textiles, foams, etc) and small components such as polymer beads. It will allow manufacturers to control the level of chemical emissions from their products (i.e. to assess ongoing conformity to regulations), to evaluate R&D prototypes and to monitor the quality of raw materials.

The new standard specifies micro-chamber parameters and outlines the test procedure. Key steps include incubating materials at 30 to 60ºC under a flow of clean, dry gas (N₂ or air) in either surface-emission mode (only one exposed surface) or in bulk emission mode. Tests typically take less than one hour. Chemical vapours emitted from the sample are subsequently analysed using TD-GC/MS (e.g. using Markes UNITY or TD-100 thermal desorption systems) or by using HPLC (formaldehyde).

D7706 also includes detailed procedures for optimising test conditions and for setting & applying emission control levels. It further describes how micro-chamber data can be correlated with longer-term reference tests using small test chambers or cells (e.g. FLEC).

Copies of the new standard are readily available from the ASTM website (www.astm.org/Standards/D7706.htm).

Markes' Micro-Chamber/Thermal Extractor provides a robust and innovative solution for screening chemical emissions from everyday products and materials. It complies fully with ASTM D7706 and with draft International standard 12219-3 (Indoor air of road vehicles - Part 3: Screening method for the determination of VOC emissions from vehicle interior parts and materials - Micro-chamber method). Markes' high-temperature Micro-Chamber/Thermal Extractor is also compatible with ISO 16000-25 (Indoor Air - Part 25: determination of the emission of semi-volatile organic chemicals from building products - Micro-chamber method).

A free copy of an informative 52-page application guide to testing chemical emissions from products and materials is available from Markes.

Markes International Ltd provides an innovative range of instrumentation, accessories and consumables for enhancing trace GC/MS analysis. Products include: thermal desorption instruments, time-of-flight mass spectrometry and related software and a broad portfolio of sampling accessories covering air sampling, materials emissions testing, breath sampling, soil gas analysis and direct desorption of volatiles from materials.

Further information is available from the company on its website www.markes.com, by email enquiries@markes.com or phone +44 (0)1443 230935.