EXPERIENCES FROM THE EMISSION CLASSIFICATION OF BUILDING MATERIALS IN FINLAND

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1 EXPERIENCES FROM THE EMISSION CLASSIFICATION OF BUILDING MATERIALS IN FINLAND E Kukkonen 1*, K Saarela 2, P Neuvonen 3 1 Helsinki University of Technology, Finland and Finnish Society of Indoor Air Quality and Climate, ( FISIAQ),Finland 2 State Technical Research Centre, Espoo, Finland 3 Building Information Foundation RTS, Helsinki, Finland ABSTRACT A renewed version of the Finnish guidelines "Classification of Indoor Climate, Construction and Building Materials" was released The classification consists of three parts; requirements for the IAQ, guidelines for construction works and classification of building materials. This third part is described here. More than 500 different building materials have already got the best M 1 labelling and it has had a positive effect on the emissions from the building materials in Finland. The classification will of course only guarantee lower levels of such chemicals, which are measured in the tests, but all stinky emissions are detected by the complementary sensory tests. The chemical testing methods are mainly basing on international standards. The sensory tests are carried out by untrained sensory panels using the acceptability scale. The reliability of the classification tests is also shortly presented. INDEX TERMS Labelling, Measuring of emissions, Emissions from materials, Improvement of building materials INTRODUCTION Practical guidelines of FiSIAQ ( Finnish Society for Indoor Air Quality and Climate) for indoor air quality and climate, including measurable target values, cleanliness requirements and emission criteria for building materials, has been in use in Finland since This classification was developed to improve the dissemination of scientific information to the practice and to encourage manufacturers of materials to develop low-emitting building products. It has been used in the design and construction of healthier and more comfortable buildings and their mechanical systems. The guideline can be used for new constructions and in evaluation of all buildings and also for renovation. The classification guidelines have been well adopted by the building branch and are although not mandatory generally referred to in design and construction contracts in Finland. Buildings with measurable better IAQ have been built. The extra costs of the use of the classification and better IAQ has shown to be only some percent of the total costs. The number of building and finishing materials accepted and labeled to the best category, emission class M1, has already exceeded 500, providing a wide selection of products covering all the major types of building materials. * Contact author esko@vartioharju.inet.fi 588

2 The classification guidelines were revised in 2001 by FiSIAQ ( FiSIAQ 2001). Many improvements were done e.g. the introduction of the guidelines for the manufacturers and constructors of air-handling equipment who wish to produce cleaner ventilation systems. Based on these principles also a system for labelling the air handling components was established in Finland in (Björkroth & al 2002.) The whole classification system is run by the Finnish Building Information Foundation RTS, and supervised by an expert committee. THE EMISSION CLASSIFICATION FOR BUILDING MATERIALS In the earlier version only finishing materials could get the M 1 labelling, but in the new version the application field has been expanded to all building materials. There are also some smaller improvements also in the requirements for testing and acceptance of the materials. Figure 1. The M1 label for building materials. To avoid harmful emissions to indoor air, all building materials and specially the finishing materials must be selected so as to keep these emissions under control. Therefore, the use of category M 1 materials is necessary for achieving the best indoor climate category S 1. Nonlabelled materials or other emissive materials can only be used in very small quantities. Category M 2 materials can be used more, up to 20% of the total amount of finishing materials in a room. Natural materials like stone, wood, glass, ceramic tiles and bricks can be used quite freely. However, the VOC emissions of the fresh wood in new buildings may be quite high; therefore these emissions must be controlled if wood is used over large surface areas. Unfortunately, the use of only low-emitting materials does not always guarantee good air quality in rooms. Ventilation also has to be adequate and the materials should be used according to the manufacturers' specifications. For example, very few materials can tolerate being exposed to excessive moisture. Materials should also be easy to hold clean. Requirements for building materials Category M 1: Category M 1 is designated for materials which fulfil the following requirements: 1) The emission of total volatile organic compounds (TVOC) is below 0.2 mg/m²h; 2) The emission of formaldehyde is below 0.05 mg/m²h; 3) The emission of ammonia is below 0.03 mg/m²h; 4) The emission of carcinogenic compounds (due to IARC) is below mg/m²h; 5) Material is not odorous (dissatisfaction with the odour is below 15%). 589

3 Category M 2: 1) The emission of total volatile organic compounds (TVOC) is below 0.4 mg/m²h; 2) The emission of formaldehyde is below mg/m²h; 3) The emission of ammonia is below 0.06 mg/m²h; 4) The emission of carcinogenic compounds (due to IARC) is below mg/m²h; 5) Material is not strongly odorous (dissatisfaction with the odour is below 30%). Category M 3: This category is for materials, which do not have emission data, or the emission data exceed the values specified for materials of category M 2. The sensory tests are carried out by naive sensory panels using the acceptability scale. The sensory emission classes of building materials are Category M1: 0.1 acceptability vote 1 Category M2: 0.2 acceptability vote < 0.1 Category M3: 1 acceptability vote < 0.2 The measurement of emissions should be performed when the material is in the final form in which it is used. Material emissions should be measured according to the proved and specified methods. The sampling and analyses of the emissive chemicals and the sensory tests have to be made according to published methods.( RTS 2001). Emissions of materials should be measured after four weeks from the date of the production or the date when the material is unwrapped from the airtight packing. The time of four weeks will be calculated for paints, levelling agents, adhesives, and sealant, among others, from the date of application on the surface of the material. It also important that the labelled materials have a product specification, which should present possible limitations for the use of the material and also requirements for the environmental conditions where the material is applied and used. The manufacturer must also have an acceptable quality control system. GENERAL PROCEDURE FOR CLASSIFICATION General instructions Applications for an emission classification for a building material are submitted to the Building Information Foundation RTS on an application form drawn up for this purpose. Applicants should enclose with their application the product specification, instructions for use, a notice on operational safety and a research report. The research report must not be more than one year old. The period of validity of the right of use of the classification M 1 label is three years. If the composition and method of manufacturing the product have not changed, the classification can be renewed by application without renewed testing, if the required testing methods and the criteria set for the products have not altered fundamentally. Both new and continuation applications will always be examined in accordance with the current requirements set for testing methods and the criteria set for the products. Sample selection, analysis and measurements of material emissions must be performed at a competent and impartial approved laboratory. A list of approved laboratories can also be found from the internet sites of RTS. 590

4 Products, packaging, product specifications or instructions for use may be labelled with the label of the emission class, normally M1, granted to the product. Product specifications should also indicate restrictions relating to the use and application of the products in particular and any aspects, which might give, rise to an increase in emissions. The manufacturer must also have an approved quality control system of the production. More detailed description of the whole testing and accepting method can be found from reference (RTS 2001) or from the home web pages of RTS. ( Chemical testing The chemical testing methods are basing as much as possible on internationally accepted or used procedures and standard nomographs ( Database 1996, ECA 1997, Nordtest 1990, Nordtest 1998 a, Nordtest 1998 b). Examples of the international standards used in the Finnish classification: CEN ENV Building products - Determination of the emission of volatile organic compounds - Part 1: Emission test chamber method. CEN ENV Building products - Determination of the emission of volatile organic compounds - Part 2: Emission test cell method. CEN ENV Building products - Determination of the emission of volatile organic compounds - Part 3: Procedure for sampling, storage and preparation of test specimens. The chemical testing methods of formaldehyde and VOCs from material emission test chambers and indoor air are drafted in ISO /ISO DIS / and /ISO DIS /. There also exist specific chamber techniques, e.g. Nordtest has a FLEC based method for chemical on-site measurements and a Climpaq chamber method for sensory measurements. These chambers can also be used for chemical measurements if they fulfil the general requirements for chambers of chemical testing. Sensory testing The sensory tests are carried out by naive sensory panels using normal acceptability scale. The sensory testing of material emissions is a complementary method to chemical testing in detection of emissions, as the sensitivity of human nose is in many cases better than instrumental methods. Moreover it is one of the methods with which consumers experiences the quality of materials in practice. ( ECA 1999) Sensory characterisation of material emissions is carried out in the Climpaq measuring chamber using a two-phase sensory test. The sensory assessments are commenced with a naive untrained sensory panel of at least five members. The mean acceptability vote is then calculated. If the acceptability vote of a sample in this panel is +0.4, the sample is seen to belong to class M1. If the acceptability vote of a sample is < 0.4, the sample will belong to class M3 and no further sensory measurements will be necessary. If the acceptability vote of a sample is between 0.4 and + 0.4, the sensory tests must be repeated using a new panel of ten more naive subjects, not be the same subjects as in the first sensory panel. The mean acceptability vote is then calculated as the mean of the ratings using the values given by at least five subjects of the first panel and ten subjects of the second panel and this result is then the final value which defines the emission class of the sample together with the results of the chemical measurements. The limits for acceptance of different classes are presented above. 591

5 RELIABILITY AND ACCURACY OF THE CLASSIFICATION PROCEDURE The reliability of the whole procedure is laying on the chemical and sensory tests done by the known, skilled and certified, or, preferable and if only possible, by officially accredited laboratories. The testing methods used in the testing procedure are basing on widely used and accepted scientific background, described in many standards and standard monographs. These classification tests are carried on however only to a limited number of test pieces, so the quality control of the manufacturers is negligible and in a key role for the constancy of the quality of the materials and products and also for the reliability of the classification. The possibility of the renewed verification tests by the accepting classification organization RTS and also the possibility of checking tests carried out by possible competitors will essentially lower the risk of intentional changes in the production processes. The common accuracy of the chemical tests will be, according to the references and experiences, about 20 %. The probable error of the sensory tests with these small two step panels (5/15) has been calculated using the assumption of T-distribution of votes and examining here only one sided deviations with a risk of 10 %. Presented in many standard textbooks of statistics.( Milton & Arnold 1986).The estimated error can be calculated basing on the knowledge, that the variance of the untrained sensory panels in this kind of tests made in Denmark (Gunnarsen & Bluyssen 1994) and in Finland has shown to be quite constantly in the range 0,4-0,6 in the acceptability scale from -1 to +1. After these calculations the probable error will shown to be of the magnitude 0,2 in the acceptability scale from -1 to +1 with the calculated risk of 10 % of wrong conclusions in the whole testing procedure. Practical tests and calculations to verify the error and risk assessment in the whole classification procedure are going on and the results will be published in the near future. In every case the overall risk of wrong conclusions in the acceptance and classification of the materials seems so to be sufficient low and functional for this very practical purpose. The principles of the calculations are more detailed presented in reference ( RTS 2001). EXPERIENCES FROM THE USE OF THE CLASSIFICATION OF BUILDING MATERIALS IN FINLAND The classification of indoor air quality and of the materials according to their harmful emissions has now been widely used in Finland for more than 5 years. The system has proven to function well in practice. Buildings with better IAQ, and also falling into the best category S 1, have been built and enhancement of IAQ has been tested and noted. Although the better IAQ may require some extra cost, this has been limited to only some percent of total building costs and very negligible when compared with the life-cycle costs and especially with the advantages better IAQ gives to the users of the building. One important issue in this process is that the manufacturers and importers of construction materials have, during these years, improved the quality of their products so much that the measured harmful emissions has been lowered drastically and even for 3 to 4 decades in some cases. The domestic as well as foreign firms have develop new products with lower emissions by using better technology in production and cleaner receipts and by laying more emphasis on product quality control. When the manufacturers have been realized that the costs of these tests are very limited compared with the advantage in the marketing of their products, they are now taking part to a more greater extent in the system. 592

6 CONCLUSIONS The Finnish classification of IAQ and building materials has proven to be a well functioning system. It has shown that private voluntary actions by the branch itself can essentially help in improving IAQ in buildings. Government co-operation and support has also proven to be important and the aim to avoid unnecessary regulations has succeeded. When rewriting the IAQ quality requirements in the Finnish Building Code the value of good IAQ for the people and for sustainability of buildings will be even more emphasised. However, there are no plans to set limits on the emissions from building materials in Finland, because the harmful emissions have already being reduced now by voluntary means, especially thanks to this classification. Certainly still much better results might have been achieved if a similar classification system could be functioning internationally. The manufacturers of the building materials and components would be then still more inclined to improve and test their products. The first step here could be the international acceptance and comparability of the test methods for building products emissions. The work of the ISO and CEN should be still more activated and directed to develop internationally accepted methods for chemical and sensory tests of the emissions from construction materials. REFERENCES: Björkroth M, Seppänen O, Säteri J, Neuvonen P, Pasanen P and Railio J (2002): Labelling system for clean ventilation systems. Indoor Air 2002, Monterey, USA Björkroth M, Kukkonen E.( 2002): Measurements of sensory load from ventilation systems by trained and untrained panels. Indoor Air 2002, Monterey, USA Database( 1996): European Data Base on Indoor Air Pollution Sources in Buildings, EU- JOULE II project, Not published. ECA (1997): European Collaborative Action Indoor Air Quality and Its Impact on Man. Total Volatile Organic Compounds (TVOC) in Indoor Air Quality Investigations, Report No 19, Luxembourg: Office for Official Publications of the European Communities. ECA (1999): European Collaborative Action Indoor Air Quality and Its Impact on Man. Sensory Evaluation of Indoor Air Quality, Report No 20, Luxembourg: Office for Official Publications of the European Communities FISIAQ( 2001). Classification of indoor climate 2000, Target values, design guidance and product requirements., FISIAQ Publication 5 E Gunnarsen L and Bluyssen P (1994): Sensory measurements using trained and untrained panels. Proceedings of Healthy Buildings 1994 Budapest, Vol 2 pp Milton & Arnold (1986): Probability and statistics in the engineering and computing sciences. Mc Graw-Hill Nordtest (1990). Building materials: Emission of Volatile Compounds, Chamber Method. Nordtest Method NT Build 358. Nordtest, Esbo, Finland. Nordtest (1998a). Building materials: Emission of Volatile Compounds On site measurements with Field and Laboratory Emission Cell (FLEC), NT Build 484. Nordtest, Esbo, Finland. Nordtest (1998b). Building Materials: Emissions of pollutants by CLIMPAQ chamber, NT Build 482. Nordtest. Esbo, Finland. RTS Protocol for Testing of Building Materials. Building Information Institute RTS Finland 2001 See also 593