VOC emissions testing - new approaches for LEED, and for CE marking in Europe

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1 VOC emissions testing - new approaches for LEED, and for CE marking in Europe Reinhard Oppl 1,*, 1 Eurofins Product Testing A/S, Galten, Denmark * Corresponding voc@eurofins.com SUMMARY By tradition, there was a large variety of volatile organic chemicals (VOC) emissions specifications, all different in limit values and testing methodology. This is changing now. The program for sustainable buildings, LEED, will change fundamentally its requirements for low-emitting interiors in LEED version 4. In Europe, a harmonized VOC emissions testing standard will be available in early This will allow including low VOC requirements into CE marking of products. Then no construction product without CE mark and thus without documentation on VOC emissions level must be distributed within the European Union, if a CE mark is applicable to that product group. Both developments will increase the availability of products with low VOC emissions. The main changes and their impact on the interior products market are described here. This development may also inspire low VOC specifications in other regions of the world. KEYWORDS VOC emissions, LEED, CE marking, regulation 1 INTRODUCTION Products with low emissions of volatile organic chemicals (VOC) into indoor air are regarded an advantage for public health in more and more countries. Regulations for reducing emissions from products into indoor air can be found only in two countries, Germany and France, even though some other European countries plan to establish similar compulsory requirements. Strongest driving force for use of low emitting products is the market where programs for sustainable buildings (e.g. LEED) and ecolabels attract more and more users (e.g. EMICODE, GUT, Blue Angel, Indoor Air Comfort, Indoor Advantage). 2 PRESENT SITUATION By history, Europe and the USA followed different approaches for characterizing low VOC emitting products, even though there are some common lines. Main similarities are: VOC emissions are characterized by simulating actual use in ventilated test chambers Testing climate is set to 23 C and 50% relative humidity of supply air Tested parameters are volatile organic chemicals (VOC) and volatile formaldehydes; mostly tested by sampling and analyzing test chamber air by o adsorption of VOCs on Tenax, thermal desorption, GC/MS; o absorption of volatile aldehydes with DNPH, solvent desorption, HPLC. Main differences are: Testing schedule o In the USA, emissions are evaluated after 14 days in test chamber (sometimes earlier)

2 o In Europe, emissions are evaluated after 28 days in test chamber (often also after 3 days, for the case of renovation and early re-occupancy) Ventilation during testing o In the USA, ventilation rate during testing is one air change per hour o In Europe, ventilation rate during testing is only 1/2 air change per hour Calculation of test results o Any test results need calculation to air concentrations in a reference room or emissions scenario, for comparison with limit values. o In the USA, several different emissions scenarios are used for private offices, openplan offices, and class rooms. A residential emission scenario is in preparation in California. This means that one and the same product can comply with the specified limit values either for one, or several, or all of the emissions scenarios. o In Europe, this is regarded too complicated for the market, and only one single European Reference Room is defined as worst-case emissions scenario for all use scenarios. This is a room of 12 m² surface and 2.5 m height with one window and one door. All products in compliance are rated against this single reference. Limit values for acceptable emissions o In the USA, most evaluation schemes limit only 35 individual VOCs taken from California list of CRELs (Chronic respiratory exposure limit values). All other VOCs remain unregulated. A new project for development of a health-based emissions standard just started that may change the way the US look at VOC emission limit values in some years. o In Europe, some specifications regulate almost 200 VOCs, other ones limit only a short list of VOCs. But all of them set limits for emissions of total VOCs (TVOC) for covering also the VOCs without individual limit values. Today each country in Europe may set its own limit values for VOC emissions. But there is an initiative that will issue Europe-wide harmonized VOC limit values in near future. 3 NEW DEVELOPMENTS 3.1 LEED The program for sustainable buildings, LEED, more or less adapted the US specifications. In recent versions, LEED required product certification by programs such as CRI Green Label Plus, FloorScore, BIFMA X7.1 and Greenguard. Recently, this has changed, and certification by a specific program is required no longer. Compliance now can be shown just by following the testing plan and respecting the limit values of any referenced program. For paints, coatings, adhesives and sealants, VOC content limits were required instead of VOC emissions limits. VOC content limits have been developed for protecting urban outdoor air against smog formation. VOC content does not correlate at all with VOC emissions into indoor air during occupancy, except initially during application. Nevertheless, when developing LEED requirements for low emitting interiors, these limits were the only low VOC program for these products available in the USA at that time. This is how these came into LEED.

3 US Green Building Council will change fundamentally its requirements for Low-emitting Interiors in LEED version 4. Details were published for a public comment period and may still be subject to changes before final conclusion on LEED version 4, planned for mid Probably the changes will be as follows (as in draft text of early 2012). LEED version 4 no longer will feature specific labels (such as CRI Green Label Plus or Greenguard). Instead LEED version 4 will require compliance with California CDPH Section (CDPH 2010) program which is not a private label but a governmental evaluation scheme. In addition to that, a TVOC limit value will not be set, but the TVOC emissions level has to be disclosed. LEED version 4 will open for an alternative pathway of compliance for LEED projects outside North America. This will be the German AgBB (AgBB 2012) evaluation scheme, but supplemented with low limit value for formaldehyde, as for French A+ class (10 µg/m³ after 28 days). Paints, coatings, adhesives and sealants will have to fulfill not only VOC content limits (as before) but also VOC emissions limits (which is new). For the VOC content limits, compliance with local law (such as European Decopaint Directive (2004/42/EC) in Europe) will be accepted as alternative pathway of compliance. While the present product-by-product approach still will be accepted, LEED version 4 will supplement this with an alternative evaluation by system (floor, ceiling, walls, insulation, and furniture). A system will be considered complaint, if all products comply e.g. screed, primer, adhesive and carpet in a flooring system. These changes will allow many more products to be included in evaluation for Low-emitting Interiors credit of LEED version 4. This will give a strong impulse for more products showing low VOC emissions into indoor air. 3.2 EUROPE Europe has gone through considerable harmonization of VOC emissions testing and limit values. German AgBB approach (AgBB 2012) not only served as basis for German regulation on limitation of VOC emissions from certain construction products into indoor air, but this approach also is taken as starting point by more and more voluntary ecolabels. Typically AgBB is understood as basic level of requirements, while the voluntary labels are setting a benchmark for the products on the market with lowest emissions. This approach consists of a limitation of total emissions of VOCs, of SVOC (semi-volatile organic compounds), and of limit values for almost 200 individual VOCs. These limit values are called LCI (Lowest Concentration of Interest) and are derived by a group of scientists by dividing an occupational exposure limit by safety factors, also taking into account additional toxicological information. A different list of such limit values was published in France (AFSSET 2009) but never reached regulatory status. French regulation on VOC emissions does not exclude high emitting products from French market. It just requires a label indicating the VOC emissions class of that product, based on VOC specifications for TVOC and for 10 individual VOCs, among those formaldehyde. CE mark is required for a number of construction products as prerequisite for being sold in any member state of European Union. CE mark can be attached to a product if it is tested with specified European standards, e.g. for mechanical stability and for burning behavior. Soon this will also include VOC emissions. Then no construction product without CE mark and thus without documentation on VOC emissions level must be distributed within the European Union, if criteria for CE marking are applicable to that type of product.

4 At present, a horizontal standard for testing VOC emissions is almost finished (CEN 2012a) and will be published as a Technical Specification, which is kind of a pre-standard. It had gone through robustness validation (CEN 2012b) and will go through a number of round robin tests before final publication. Main findings of the robustness validation were: Temperature had some impact on specific emission rate but less than expected. Relative humidity of supply air had some but weaker impact on specific emission rate. Test chambers with volume between 0.02 m³ and 3 m³ gave equivalent specific emission rates. Higher loading factor had some impact on specific emission rate for some products. Higher ventilation rate had some impact on specific emission rate for some products. o But the present tolerance intervals for above parameters were confirmed by the study. On-site wet-applied products can give falsified increased level of emissions due to remainders of high initial emissions being re-desorbed from test chamber walls later during test. o This is different from reality where typical indoor walls will not show that strong redesorption rate. o This can be solved by some days of pre-conditioning the fresh test specimen in separate chambers, before actual start of test. o For similar reasons test specimen shall remain in test chamber all the time during testing. Sample age at start of test showed to be important for one product and not so important for several other products. If only emissions from top surface are relevant then edges and back shall be sealed. o Most efficient techniques were back to back storage of plates, with edges covered with aluminum tape, tight coverage of edges and back with aluminum foil, seal box as specified in JIS A Homogeneity of emissions of most tested products was between <10% and 20% RSD. o Any observed change of test result when changing a testing parameter (e.g. temperature) has to be larger than material inhomogeneity for being considered significant. Using a solid reference material for toluene (Cox et al. 2010) gave recovery of % in most involved test chambers. o This was considered as benchmark. Low benzene artifact levels can be generated on clean air sampling tubes during air sampling. o Low-level benzene test results should be verified with an independent second testing method before comparing a test result with any low limit value of e.g. 1 µg/m³. First version of that horizontal standard is expected to be published in early 2013 as CEN Technical Specification (TS). Then different product standards, e.g. for floor coverings, will be revised for including VOC emissions. These standards will not re-define testing method but reference to that forthcoming horizontal VOC emissions standard or TS this is why that standard is called horizontal, meaning that it will be used by a variety of specific product standards. This process will start in The testing standard will follow the principles outlined above. As regards testing, it will specify certain ranges for ventilation and loading factor that will allow running one test only for reporting in line with several testing protocols: The new EN standard, European formaldehyde testing norm EN 717-1, ANSI and ASTM standards, and CDPH Section 1350 see table 1. The robustness validation study confirmed that keeping testing parameters within these ranges will not deteriorate the test result and its reliability.

5 Table 1: Parameters during testing Parameter during Most US standards Draft EN standard EN testing (ANSI, ASTM, CDPH) Temperature, C 23 ± 1 23 ± ± 1 Relative humidity, % 50 ± 5 45 ± 3 50 ± 5 Loading factor, m²/m³ < 50% of ref.room to > 50% of ref.room max. 2.0 Ventilation rate, ach Please note: These parameters are different from loading and ventilation in emissions scenarios and reference rooms. The parameters here are specified just and only for actual testing. CE marking will not set limit values for VOC emissions into indoor air. Limit values will be defined by each member state of the European Union, and these will never be the same in all of these countries. CE marking approach goes for assigning technical classes that mirror all of the existing national regulatory limit values. This includes the possibility that a CE marked product can be sold in some Member States of the EU, but not in other ones, depending on the national VOC requirements. As CE marking relies on regulations that specify the required minimum performance in terms of low VOC emissions, voluntary labels will continue setting more stringent limits for their respective programs. CE marking and expected additional national legal requirements will increase rapidly the number of products with low VOC emissions available on European market. 4 DISCUSSION Several regions even outside Europe and the USA see attempts to establish upper limits for VOC emissions into indoor air. Number of regulations, of voluntary labels or of regional LEED specifications in terms of low VOC emissions will increase. It could be an advantage if not each country re-invents the wheel but if new specifications would use the same testing requirements if not the same limit values as used elsewhere in the world. This would ease the burden of testing costs for manufacturers. Then tested local products would have better starting position on the market if exported to the USA and to Europe, as well as products from the US and Europe would be available more easily in other regions if low VOC emissions are required there. 5 CONCLUSIONS VOC emissions testing becomes more and more relevant in many regions. Two main approaches are available for rating VOC emissions into indoor air. While US approaches target a small number of individual VOCs, European approaches reach out longer and try to cover all volatile organic emissions. Differences between test methods are reduced with a forthcoming European horizontal testing standard for low VOC emissions that in future will be used for CE marking.

6 6 REFERENCES AFSSET Avis relatif à une procédure de qualification des émissions de composés organiques volatils par les matériaux de construction et produits de décoration. Paris: AFSSET / ANSES. AgBB Ausschuss zur gesundheitlichen Bewertung von Bauprodukten, Evaluation Procedure for VOCs from Building Products, Committee for Health-related Evaluation of Building Products. Berlin. CDPH CDPH (California Department of Public Health), Standard method for the testing and evaluation of volatile organic chemical emissions from indoor sources using environmental chambers, Version 1.1, February CEN. 2012a. Document TC 351 WI of CEN/TC 351/WG 2, Construction products Assessment of emissions of regulated dangerous substances from construction products. Paris: AFNOR. CEN. 2012b. Document N 173 of CEN/TC 351/WG 2, Final presentation of test data for Robustness Validation of Methods developed by CEN/TC 351/WG 2. And: Document N 174 of CEN/TC 351/WG 2, Robustness Validation of Methods developed by CEN/TC 351/WG 2 Presentation and interpretation of the data obtained, and proposals to amend accordingly the draft Technical Specification N 129. Paris: AFNOR. Cox, S. S., Liu, Z., Little, J. C., Howard-Reed, C., Nabinger, S., and Persily, A Diffusion-Controlled Reference Material for VOC Emissions Testing: Proof of Concept, Indoor Air, 20(5),