EMISSION TESTS ON THERMAL INSULATION PRODUCTS WITH THE INTENTION TO IMPLEMENT THESE TESTS INTO EN STANDARDS

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1 EMISSION TESTS ON THERMAL INSULATION PRODUCTS WITH THE INTENTION TO IMPLEMENT THESE TESTS INTO EN STANDARDS W Horn *1, R Gellert 2, O Jann 1, S Kalus 1 and D Brödner 1 1 Federal Institute for Materials Research and Testing (BAM), Berlin, Germany 2 Forschungsinstitut für Wärmeschutz e.v. München (FIW), Munich, Germany ABSTRACT For insulation material - as for all the other indoor relevant construction products - no emission tests are implemented in the relevant EN product standards. Therefore a research study started financed by the German Ministry of Transport, Building and Housing (BBR). Several chamber types were compared for measuring insulation material. Compounds like pentane, styrene, ethanol or formaldehyde have been detected. In these tests compounds belonging to the group of very volatile organic compounds (VVOC) were mostly those with the highest concentrations. The emission tests for VVOCs, VOCs and odour were done 1, 3, 10 and 28 after loading. The results of the study were evaluated with the AgBB Scheme. It is shown that the results of the tests in a 1 m³ emission test chamber have a good comparability to the tests in an emission cell equipped with a special subunit. INDEX TERMS insulation material, VOC emission, chamber comparison, construction products directive, AgBB-scheme INTRODUCTION In October 2001 ten European standards (EN through EN 13171) were introduced in Germany dealing with insulation materials and products. Still existing national standards had to be withdrawn. The new standards now in effect had to be based on the European Construction Products Directive (CPD) and conceptual details had been mandated by the European Commission to the standardization body CEN. Among other properties like thermal conductivity and fire performance the mandate requested to standardize a so called initial type test (ITT) for the release of dangerous substances (now called regulated substances ) to be performed by an independent testing laboratory on behalf of the manufacturer before placing the product onto the market. However, due to the lack of experience and due to a non existing European wide harmonization a common method for testing and classification of this property could not be included in the standards in due time and reference was only made to national regulations. Since within the next few years this shortcoming has to be overcome in order to CE mark the products e.g. for indoor use, enough pressure and interest had build up to start a research project funded by the German government (Ministry of Transport, Building and Housing (BBR), project number: Z ) and executed by FIW Munich and BAM Berlin. The research project started in 2003 and its main objective was to develop a cost effective and very practical test method suitable as an initial type test (ITT) for the determination of emissions from thermal insulation materials and products in particular volatile organic compounds (VOC) - factory made in accordance with EN (mineral wool), EN (EPS), etc. through EN (wood fibre products). Starting point for the work were the testing facilities at BAM in Berlin where tests according to the draft standards ISO (emission chamber) and ISO (emission cell) could be performed. Using both types of emission test equipment, cell and chamber, tests were performed with polyurethane (PU) foam, mineral wool (MW), expanded (EPS) and extruded polystyrene (XPS), phenol resin foam (PF) and foamglas (CG). The emission tests for VOCs and odour were done 1, 3, 10 and 28 after loading. Parallel to the emission tests FIW Munich would initially test the other building related properties to make sure that the products in question were fit for the market and then take over the emission test that had proved most suited and verify its ITT validity. Emission data collected that way were then to be plugged into the AgBB evaluation scheme (AgBB: Committee for Health-related Evaluation of Building Products) for the classification of building materials and products for * Contact author wolfgang.horn@bam.de 1886

2 indoor use (Däumling 2005, AgBB 2004). RESEARCH METHODS Products And Product Preparation All products were received from producers. They were delivered in the typical dimensions for the market. For cell tests a circular piece with a diameter of 15 cm was cut out of the material. This piece was transferred in to the -subunit with a height variable bottom with a maximum thickness of 12 cm. The bottom was fixed so that the surface of the material has the same orientation as the edge of the subunit. Afterwards the was placed on the equipped subunit. For 3 -chamber tests the plates were cut into pieces of 100 x 50 cm 2. One plate of the insulating material was placed in a stainless steel frame (L-profile). On the bottom of this first frame an aluminium plate with 100 x 50 cm 2 sealed the back side of the sample. A second frame was put on top. Both frames were fixed with self-adhesive aluminium foil. Thus the cutting edge and the back side of the plates were completely sealed. An emitting surface of 0.47 m² per side and 0.94 m² for two plates resulted. Directly after the sealing the plates were inserted in a 1 m³ emission test chamber. Following this procedure both emission tests, chamber and FELC, were performed in the same manner. Chamber Measurements In this study cells and 3 -emission chambers should be compared for their suitability in testing insulation material. All tests were done at 23 C, 50 % relative humidity and an area specific air flow rate (q) of approximately 1 m 3 m -2 h -1. Two types of emission cells were employed: a and a self constructed cell () based on a top of a reaction vessel equipped with a flat flange bottom and four connectors two for air in- and outlet one for sampling and one for a mixing blade were employed (Wilke 2004). Both cells were equipped with a -subunit for the measurement of insulation material. Sampling And Analysis For sampling of VOCs Tenax sampling tubes are proven to be the best adsorbent for many compounds (ISO ). Up to 5 l of chamber air were sucked through the tube with 100 ml per minute. Sampling was done at the 1 st, 3 rd, 10 th and 28 th day. Before sampling 1 µl internal standard solution (Cyclodecane in Methanol) was added to the sampling tube. Identification and quantification with GC/MS followed. The results were calculated using the internal standard method in comparison with calibration curves. The limits of determination (LD) depended strongly on the compounds analysed and for the most of them they are in the range of 1 to 10 µg m -3. Aldehydes and ketones, e.g. formaldehyde or acetone, can be sensitively detected with (2,4-dinitrophenyl)hydrazine (DNPH). The products of the reaction of aldehydes or ketones with DNPH can be detected by high pressure liquid chromatography (HPLC) (ISO ). For the sampling commercial solid phase samplers from Supelco were used, which consists out of a silica gel treated with the derivatization agent DNPH. On the 1 st, 3 rd, 10 th and 28 th day samples were taken from the chamber air. With a sampling rate of 500 millilitres / minute a volume of 30 litres was taken. The used sampling cartridges were stored between 6 and 8 C. Aldehydes were analysed using HPLC with UV detection following extraction of the aldehyde sampler cartridges with 2 ml of acetonitrile. The quantitation limit for the aldehyde-dnph derivative was about 0.1 ng µl -1. The estimated quantitation limit for individual aldehydes ranged from approximately 1 μg m -3 for formaldehyde to 2 μg m -3 for decanal. RESULTS The results of all products tested in emission chambers were evaluated using the AgBB scheme (Table 1). TVOC 3, 28 : sum of the concentration of all individual substances with concentrations equal or greater than 2 µg/m³ within the retention range C6 - C16 on a nonpolar column. (In accordance with ISO ) TVVOC 3, 28 : sum of the concentration of all individual substances below the retention range of C6 on a nonpolar column. TSVOC 28 : sum of the concentration of all individual substances with concentrations equal or greater than 2 µg/m³ within the retention range > C16 - C22 on a nonpolar column. R: sum of all R i (R i = C i / LCI i ) which is the ratio between the concentration of an individual substance and its LCI value (lowest concentration of interest) for the details see ECA (1997) and AgBB (2004). Compounds without LCI value were listed under the non-assessable VOC. 1887

3 As can be seen in Table 1 the VVOC concentrations are the highest of all tested compounds. The tested materials emit the following very volatile compounds: Pentane (EPS, PUR), Ethanol (XPS), Formaldehyde (MW, PF), 2-Chloropropane (PF). Additionally, Ethylbenzene, Styrene, Benzaldehyde, Propylbenzene, Acetophenone (EPS), Triethylphosphate (PUR) Acetic acid and Toluene (PF) from the VOCs can be detected. Table 1. Overview of the results for insulation material with the AgBB evaluation scheme. All products fulfill the AgBB requirements. (Sum of Carcinogens after d3 > 10 µg/m³; d28 > 1 µg/m³ could not be detected). Criteria / non-asses-sable TVOC Material 3 TVVOC 3 TVOC 28 TSVOC 28 TVVOC 28 R VOC µg/m³ µg/m³ µg/m³ µg/m³ µg/m³ µg/m³ Requirements 10,000-1, EPS , XPS , MW PUF PRF , , FG The study was designed to implement low cost emission tests into standard procedures. Therefore the comparison of 3 -chamber tests with the easier to handle cell is an important part of this work. The thickness of insulation material up to 15 cm and above made it necessary to use chambers with a dimension above 100 l. Otherwise the chambers might be overfilled with the sample. Figure 1 shows the courses of the emission curves from Pentane and Styrene emitted from EPS They were investigated in the three different emission devices. The standard deviations in percentage of the emission rate after 28 were 3 % for Pentane and 15 % for Styrene Pentane 300 Styrene SERa in 礸 /m 瞙 SERa in 礸 /m 瞙 Figure 1. Slope of emission curves from Pentane and Styrene emitted from EPS 3443 in emission cells (, ) and the 3 -chamber. Similar emission curves were also received for the emission of Formaldehyde from Mineral Wool (MW 3474) as can be seen in Figure 3. The standard deviation in percentage of the emission rate after a testing period of 28 was 17 %. DISCUSSION Virta (2005) and Koivula (2005) designed a special chamber for emission tests of insulation material and other construction products. Their chamber is build up to measure biological and chemical emissions in one chamber type. Unfortunately this chamber is used with an air exchange rate of up to 100 h -1 so that the results are not 1888

4 comparable to our investigation. They have also performed tests of MW samples but without checking Formaldehyde. Alevantis (2003) found formaldehyde from MW between 0.5 an 20 µg m -2 h -1 after a testing period of 14 in chamber tests (10 of conditioning, 4 of chamber test). The evaluation of the emissions from the insulation materials using the AgBB-scheme shows that in this type of products all investigated materials fulfill the requirement. The highest concentration was found for VVOC. This group of compounds is not yet considered. In the future this classification will be incorporated. Nevertheless, the AgBB scheme is a well suited tool for the evaluation of building compounds. SERa in 礸 /m?h Figure 2. Slope of emission curves from Formaldehyde emitted from MW 3474 in both emission cells (, ) and the 3 -chamber. CONCLUSION AND IMPLICATIONS The standard deviation when comparing the three chambers/cells seems to be in a satisfying order of magnitude with a value of up to 20 %. With those results the recommendation to the FIW Munich was given to build up an emission test facility based on a. Nevertheless the self constructed emission cell is also suitable in the same manner. Very important is the usage of a subunit which is an appropriate seal against the surrounding air. From some materials only one product was tested so that the results cannot be considered representative for the whole variety of products in their respective classes. However, the study was designed to develop a test method, which is easy to handle and with low costs for a single test. The method could be a basis for future European Standards. ACKNOWLEDGMENTS The financial contribution of the Ministry of Transport, Building and Housing (BBR) to this study is gratefully acknowledged REFERENCES AgBB (Committee for Health-related Evaluation of Building Products) Health-related Evaluation Procedure for Volatile Organic Compounds Emissions (VOC and SVOC) from Building Products. Avelantis L Building Material - Emissions Study. California Integrated Waste Management Board. Däumling C., Brenske KR., Wilke O., Horn W., Jann O Health-related evaluation of VOC and SVOC emissions from building products a contribution to the European construction products directive. Gefahrstoffe, Reinhaltung der Luft. Vol 65, in press ECA (1997) (European Collaborative Action "Indoor Air Quality and its Impact on Man"): Evaluation of VOC Emissions from Building Products Solid Flooring Materials. Report No. 18, EUR EN, European Commission, Joint Research Centre, Environment Institute 1889

5 Horn W., Müller B., Jann O., Däumling C., Kalus S., Brödner D Emission and odour measurement of construction products evaluated using a German construction product evaluation scheme. Proceedings of the 10th International Conference on Indoor Air Quality and Climate - Indoor Air 05, In press. Beijing, China. ISO Determination of formaldehyde and other carbonyl compounds - Active sampling method. ISO 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/FID. ISO (Draft). Determination of the emission of volatile organic compounds 09: Emission test chamber method / 10: Emission test cell method / 11: Sampling, storage of samples and preparation of test specimens. Koivula M., Kymäläinen HR., Virta J., Hakkarainen H., Hussein T., Komulainen J., Koponen H., Hautala M., Hämeri K., Kanerva P., Pehkonen A., Sjöberg AM Emissions from thermal insulations part 2: evaluation of emissions from organic and inorganic insulations. Building and Environment in press Virta J., Koivula M., Hussein T., Koponen S., Hakkarainen H., Kymäläinen HR., Hämeri K., Kulmala M., Hautala M Emissions from thermal insulations part 1: development and characteristics of the test apparatus. Building and Environment in press Wilke O., Jann O., Brödner D VOC and SVOC-emissions form adhesives, floor coverings and complete floor structures. Indoor Air. Vol. 14. Supp