WHAT IS BEHIND TVOC IN M1 -CLASSIFIED CONSTRUCTION AND FINISHING MATERIALS VTT S EXPERIENCE

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1 WHAT IS BEHIND TVOC IN M1 -CLASSIFIED CONSTRUCTION AND FINISHING MATERIALS VTT S EXPERIENCE K Saarela *, K Villberg and T Tirkkonen VTT Building and Transport, Espoo, Finland ABCTRACT The Finnish Classification of Indoor Climate, Construction and Finishing Materials was first published in 1995 revised in year 2000 (Classification of Indoor Climate 2000). One part of the requirements consists of Emission Classification of building materials. The aim of establishing the classification is to enhance the development and use of low-emitting building materials. TVOC was chosen as one criterion representing the whole group of VOCemissions as the emission testing procedure should be simple, well defined for different building material categories, cost effective and fulfill the requirement of pre-defined, short testing time and cost. Up today 500 building materials have been granted M1 label. This study overviews how well the TVOC-concept covers the possible health- and comfort effects of the single VOC-emissions. INDEX TERMS Material Emissions, TVOC, VOC, Label, Classification INTRODUCTION In the Finnish Classification materials are classified according to TVOC emission, ammonia and formaldehyde emission and sensory evaluation. Materials applying for the Emission Class M1 label shall fulfil the following requirements: TVOC emission (as toluene equivalents) below mg/m²h, formaldehyde emission below 0.05 mg/m²h, ammonia emission below 0.03 mg/m²h and the number of dissatisfied with the odor below 15 %. The question often asked is if TVOC is a relevant criterion to be used in material emission classification? Or should the requirements for VOC emissions be based on the emission of single compounds or a combination of these two factors? In some materials the TVOC emission consists of numerous single VOCs at relatively low concentrations. Some materials have more characteristic emissions consisting of few main components. VTT Chemical Technology has during the last 10 years performed at least 1500 material emission tests of which nearly 1000 are in line with the requirements of the testing protocol used since 1995 and further developed for the material classification (The Building Information Foundation). This data is stored into our material emission database during more than 10 years. In this presentation the TVOC data of materials measured in VTT are dismantled into single VOCs within selected main material categories to demonstrate the contribution of single VOCs in the TVOC emission from different materials. This study is made to evaluate the validity of using TVOC value in predicting the resulting indoor air quality and comfort when M1 classified building materials are used. * Contact author kristina.saarela@vtt.fi 619

2 In VTT there are also other studies going on aiming at evaluating and developing the classification and studying its realization in new residential buildings (H Jarnstrom et al, 2002), and on the other side we are studying which compounds in indoor air generally correlate with health or comfort problems in the building stock (K Villberg et al, 2002). METHODS The material emission measurements have been performed from 28 days old test specimen conditioned in a clean room with the same climate parameters used in the chamber testing. The paints have been applied on an inert surface using a paint applicator blade giving a final dry film thickness of µm (ECA 1995) and the adhesives with a notched trowel according to manufacturers directions. The test chambers have been operated according to Nordtest (Nordtest 1990) and the specifications by ECA (ECA 1995) and the Database project (Database EU Joule II+). The emissions have been collected on Tenax TA and analyzed with a gas chromatograph equipped with FID/MSD. The TVOC-value is defined as the detector response between C6 - C16 in toluene equivalents. Single VOCs were identified from MSD total ion chromatogram and quantified in toluene equivalents using FID. The results have been stored in an Access -database and the data is treated with the SPSS statistical program. The emissions results TVOC- and the highest single VOC-emission as geometric mean, GM, are given for selected material categories with typical, material specific emissions often blamed for causing indoor air problems. The results are divided into two groupings. Materials in the first group would for the TVOC-values fulfil the M1 requirements and in the group, outliers, would fall out of the TVOC-requirement in the M1 classification. RESULTS An overall view as TVOC-value of the studied materials emissions is given in Figure 1. 0,800 [mg/m2 h] 0,700 0,600 0,500 N=6 M1 M 1 outliers 0,400 0,300 0,200 N=12 N=6 N=102 N=3 N=60 0,100 0,000 N=48 PVC N=16 Adhesives N=37 Paints N=30 Parquets N=307 All materials M1 M 1 outliers Figure 1. Geometric mean of TVOC emissions from a selection of M1 classified materials. N indicates the number of the materials in each material category. 620

3 The TVOC-emission of the material categories in Figure 1 are in the following Figures 2-9 broken down to TVOC of single materials and the most abundant single VOC-emission included in the respective TVOC-value is shown. For PVC and paints only the data exceeding the median of the TVOC-emission in these material groups are reported due to high number of cases. Extract of PVC M1 materials w ith above median 2-Pentanone, 4-methyl- 1-Octanol 1-Octanol Acetic acid, octyl ester Phenol TXIB Benzene, (1,1-dimethyldecyl)-, 2-ethyl- Benzene, (1,1-dimethyldecyl)- Benzene, methyl- 2-Pyrrolidinone, 1-methyl- Dodecane, 2,6,11-trimethyl- TV OC SER 0,000 0,050 0,100 0,150 0,200 0,250 0,300, 2-ethyl- 1-Propene, 2-methyl-, trimer Ethanol, 1- (2- butoxyethoxy)- PVC M1 outliers 0,000 0,100 0,200 0,300 0,400 0,500 0,600 Figure 3. TVOC- and corresponding maximum VOC-emission [mg/m²h] of M1-class outliers. Figure 2. TVOC emission of PVC M1-class materials above the median and maximum emission [mg/m²h] of the most abundant single VOC contained in the TVOC-emission. l A summary of the data from figures 2 to 9 is given in statistical terms in Table 1 showing the geometric mean, GM, and the 90 percentile values of TVOC emission of each material, 90 percentile value of the highest single VOC emission included in the TVOC emission in each material category. Also the 90 percentile values of the maximum percentage of a single VOC included in the TVOC value are given. The concentration of the main emissions are given with available odor and health data on these compounds. 621

4 Adhesives M1 Adhesives M1 outliers (BHT) 1,2-E thanedio l Junipene 1,2- Propanediol Ethanedioic acid, bis(trimethylsilyl) ester BHT Ethano l, 2-(2- buto xyetho xy)-, acetate Junipene Ethano l, 2- pheno xy- Benzenemethanol Ethano l, 2- pheno xy- Ethano l, 2-(2-buto xyetho xy)-, acetate P heno l, 4-chlo ro -3-methyl- Ethano l, 2-(2-buto xyetho xy)-, acetate 4-(1,1-dimethylethyl)pheno l tri-n-butylpho sphate Ethano l, 2-(2-buto xyetho xy)-, acetate 0 0,05 0,1 0,15 0,2 0,25 0,000 0,500 1,000 1,500 2,000 2,500 Figure 4 (on the left). Adhesives. TVOC- and corresponding maximum VOC-emission [mg/m 2 h] of M1-class. Figure 5 (above). Adhesives. TVOC- and corresponding maximum VOC-emission [mg/m 2 h] of M1-class outliers M1 Paints TVOC over Paints M1 outliers Benzenemethanol Benzene, ethyldimethyl- alpha-terpineol aldehyde? Ethanol, 2-(2- butoxyethoxy)- 1,2- Propanediol 2,5,8,11-Tetraoxatetradecan-13-ol, 4,7,10- trimethyl- Ethanol, 2-(2-ethoxyethoxy)- Texanol 1 Texanol SER maxvoc 1,2- Propanediol 0,000 0,200 0,400 0,600 0,800 Figure 6 (on the left). TVOC emission of Paint M1-class materials above the median, and max. emission [mg/m 2 h] of the most abundant single VOC contained in the TVOC-emission value. Dowanol 0,00 0,05 0,10 0,15 0,20 0,25 0,30 Figure 7 (above). Paints. TVOC- and corresponding maximum VOC-emission [mg/m 2 h] of M1-class outliers. 622

5 M1 Parquets Parquets M1 outliers alpha-pinene Hexadecane Hexana l Benzene, methyl- A cetic acid,a LPHA,- PINENE Heptane Methanone, diphenyl- SER max V OC SER TV OC beta-pinene 0,000 0,100 0,200 0,300 0,400 l-beta-pinene Phenol,ALPHA,-PINENE alpha-pinene A cetic acid alpha-pinene Tetrahydrofuran Benzaldehyde M ethanone, diphenyl- Phenol M ethanone, diphenyll-beta-pinene Figure 8 (on the left ). Parquets. TVOC and corresponding maximum VOC-emission [mg/m 2 h] of M1-class Figure 9 (above). Parquets. TVOCand corresponding maximum VOCemission [mg/m 2 h] of M1-class outliers. 0,000 0,050 0,100 0,150 0,200 0,250 Table 1. Statistical data on the TVOC- and VOC concentrations of the material categories as geometric mean and 90 percentile values, and the 90 percentiles of single maximum VOC concentration- percent contained in the TVOC-value. Category Number of materials, N TVOC,mg/m 2 h GM TVOC,mg/m 2 h 90 %-value VOC, mg/m 2 h 90 %-value All materials M ,042 0,176 0, non M1 60 0,544 0,480 0, PVC M1 48 0,059 0,197 0, NonM1 12 0,343 0,480 0, Adhesives M1 16 0,029 0,112 0, non M1 6 0,758 2,017 1, Paints M1 37 0,031 0,140 0, non M1 6 0,417 0,561 0, Parquets M1 30 0,059 0,050 0, non M1 3 0,295 0,348 0, Percent of max VOC in cluded intvoc, 90 %- value 623

6 In the M1 classifying materials emission of the following compounds exceeded 100 µg/m 2 h: 2-(2-butoxyethoxy)ethanol (=Dowanol),, 2-(2-butoxyethoxy)ethanol acetate, tri-nbutylphosphate, Texanol, TXIB and the following emissions exceeded 50 µg/m 2 h: cyclohexanone, 1-methyl-2-pyrrolidinone, 1,1-dimethyldecylbenzene, hexanal, alphapinene, BHT, acetic acid, 2-butoxyethyl ester, Styrene, decanal, 2,4-pentanedione, 1,2- benzenedicarboxylic acid diethyl ester, p-xylene and undecane. Of these, the compounds written in bold, are neuro toxicants or suspects or other toxicants. Styrene belongs to group II B on IARC carcinogen list. In Finland the Ministry of social- and health affairs has published an Indoor Air Guideline in which the recommended maximum concentration of styrene in indoor air is 70 µg/m 3 mainly set on the basis of odor. In some cases decanal exceeded the odor threshold (Devos et al. 1990) 0,006 mg/ m 3 and hexanal was at the threshold 0,058 mg/m 3 when using the Nordtest (Nordtest 1990) modeling for chamber concentration. In M1 outliers the highest concentration on 2-phenoxy-Ethanol, nearly 2000 µg/m 2 h and more than 600µg/m 2 h of 2-(2-butoxyethoxy)-acetate ethanol were detected in an adhesives, and over 400 µg/m 2 h of 2-(2-butoxyethoxy)- ethanol (Dowanol ) in a paint. DISCUSSION According to Table 1, in the paints and adhesive categories, there are more dominant single VOCs included in the TVOC-value as in the other categories, and as seen from Figures 4 and 6, their emissions exceed 50- and even 100 µg/ m 2 h. Some of them are neurotoxicants or suspects. In M1 outliers these compounds are several times higher. Restricting the TVOCemission clearly cuts down also the single emissions, but so far we do not have enough knowledge where to set the limit. The ECA Guideline (ECA 1997) uses the LCI, lowest concentration of interest, in the proposed material emissions guideline. None of above detected compounds exceed these values. In this random sample some of the single VOC-emissions exceed the odor threshold. It has been noticed in several cases that the emissions of single VOCs do not exceed odor threshold values and yet the emissions are perceived as odorous. For this reason the Building Material Classification also requires an acceptability test for the emission odor. In fact it has more often today been noticed, that even if the chemical emission tests show only very low emissions, the material does not pass the sensory evaluation. REFERENCES The Building Information Foundation, Classification of Indoor Climate 2000, Finnish Society of Indoor Air Quality and Climate (FiSIAQ), publication 5 E. Database EU Joule II+: European Data Base on Indoor Air Pollution Sources in Buildings, EU- JOULE II+ Program, Devos M, Patte F, Rouault J, Laffort P, and Van Gemert L J Standardized Human Olfactory Thresholds. New York: Oxford University Press. ECA (1995), European Collaborative Action Indoor Air Quality and Its Impact on Man. Determination of VOC's emitted from indoor materials and products. Second interlaboratory comparison of small chamber measurements. Report No 16 (EUR EN). ECA European Collaborative Action Indoor Air Quality and Its Impact on Man. Evaluation of VOC Emissions from Building Products, Report No 18, Luxembourg: Office for Official Publications of the European Communities. H Jarnstrom and K Saarela, Indoor Air Quality and Material Emissions in new Buildings, submitted to the Proc. of the 9 th International Conference on Indoor Air Quality and Climate - Indoor Air K Villberg, K Saarela, H Mussalo-Rauhamaa, M Malmberg and T Haahtela, Correlation between VOCs emitted from building materials and diagnosed building related symptoms, submitted to the Proc. of the 9 th International Conference on Indoor Air Quality and Climate - Indoor Air Nordtest (1990). Building materials: Emission of Volatile Compounds, Chamber Method. Nordtest Method NT Build 358, Esbo, Finland: Nordtest. 624