Proficiency testing (PT) is offered alternatively with and without own sampling. Participants may choose whether they wish to perform sampling for volatile organic compounds themselves, or to have the self-conditioned loaded sample carriers supplied to them [1].
The PT scheme consists of two runs with different concentrations of the same substances within the test gas. The test gas will contain up to ten different substances. To exclude blank values in the basic gas and the test gas stream a blank value of the basic gas will be taken at the beginning of a test series.
The concentrations to be measured will lie within the range between 10 to 200 µg/m3 for each substance. The concentration of benzene will lie close to the acceptance concentration of 0.2 mg/m3 (60 ppb) [2].
Analysis has to be conducted by gas chromatography by means of thermal desorption according to DIN EN ISO 16017-1 [3], DIN EN ISO 16000-6 [4] or IFA Folder No. 8936 [5].
For benzene the method according to IFA-Folder No. 6265, measurement method No. 2 [6] can be used.
The quantitative evaluation should be based on the substance, so please do not quote the results as toluene equivalent.
Substance group | Substances |
---|---|
Alkanes | n-decane, n-dodecane, n-heptane, n-hexadecane, n-hexane, n-nonane, n-octane, pentadecane, n-tetradecane, n-tridecane, n-undecane |
Alcohols | butan-1-ol, 2-ethyl-1-hexanol |
Aromates | benzene, 3-carene, cumene, ethylbenzene, limonene, α-pinene, toluene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, o-, m-, p-xylene |
Esters and Ethers | n-butyl acetate, 2-butoxyethyl acetate, 2-(2-butoxy ethoxy)-ethyl acetate, 2-ethoxy ethylacetate |
Ketones and aldehydes | butan-2-one, hexanal, acetophenone, 4-methyl-2-pentanone |
Siloxanes | hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane |
A large-scale dynamic test gas stream can be found at the IFA. It is suitable for parallel sampling by up to 25 participants.
Participants will receive detailed information on the PT, a description of the apparatus and the connections for the sampling devices in particular, and a list of the substances to be analysed in good time.
The production of samples for volatile organic compounds is conducted at the dynamic test gas stream of the IFA. The particular feature of this PT scheme is that thermal desorption tubes are employed for loading which must be conditioned by the participants prior to the PT. Each participant (analysis laboratory) submits seven thermal desorption tubes to the IFA. The sample tubes and the blank value tubes will be loaded with a sampling volume of 2 l. Only personal air samplers are used at the IFA. The sample carrier should not generate a back pressure exceeding 5.0 kPa under the specified conditions. Where internally fabricated sample carriers are used, please supply an adapter (GL14/GL25 threaded connection) for the test gas stream.
Each participant receives a sample kit comprising:
[1] Ringversuch Flüchtige Organische Verbindungen VOC mit Thermodesorption (Kennzahl 1630-3) In: IFA-Arbeitsmappe Messung von Gefahrstoffen.
[2] Technical Rule for Hazardous Substances 910: Risk-related concept of measures for activities involving carcinogenic hazardous substances (TRGS 910). Version: February 2014.
[3] DIN EN ISO 16017-1: Indoor, ambiant and workplace air - Sampling and analysis of volatile organic compounds by sorbent tube/thermal desorption/capillary gas chromatography - Part 1: Pumped sampling (10.01). Beuth, Berlin 2001
[4] DIN ISO 16000-6: Indoor air - Part 6: Determination of volatile organic compounds in indoor and test chamber air by active sampling on Tenax TA® sorbent, thermal desorption and gas chromatography using MS or MS-FID (ISO 16000-6:2011). Beuth, Berlin 2012
[5] VOC (Volatile Organic Compounds, Flüchtige Organische Substanzen) (Kennzahl 8936). In: IFA-Arbeitsmappe Messung von Gefahrstoffen.
[6] Benzol, Messverfahren Nr. 2 (Kennzahl 6265). In: IFA-Arbeitsmappe Messung von Gefahrstoffen.