building material

Under the aspect of consumer protection different kinds of labelling systems for materialemissions have been developed in many European countries and by industrial organizations.Despite a common market there is no harmonized system for material emission available inEurope. In the second half of 2001, the European Collaborative Action on Urban Air, IndoorEnvironment & Human Exposure established a working group to bring forward theharmonization of the indoor material labelling schemes at European level.

The Healthy Building Technology Programme was established in Finland to abolish thefactors causing building related problems as it was clearly seen that deficiencies in indoor airhad an economical importance even at the national level (Rantama, 2003).

A very important issue for all activities for better IAQ in Finland has been the introduction of theclassification guidelines for indoor air quality and climate. These guidelines, published by FISIAQ,including measurable target values, cleanliness requirements and emission criteria for buildingmaterials, have been in use in Finland since 1995 and were revised in 2001.An essential part of the successful IAQ classification has been the emission classification ofconstruction materials.

Building environmental performance evaluation should make use of a life cycle assessment(LCA) approach, by considering all building process phases: raw material acquisition,manufacture, transportation, construction, use or operation, decommissioning, disposal andre-use. Such an approach is intended to measure, not only impacts on natural and non-naturalresources but also building indoor environmental quality (IEQ).

Evaluation of emissions from building products is mainly focused on comparison betweenexposition concentrations of identified individual organic compounds and health criteria. Noadequate integrated criterion is available for interaction and mixture effects. Besides,everyone performs daily evaluation of perceived air quality. Human beings through theirsenses, for example, olfaction and chemesthesis, are able to achieve a synthetic response to aglobal mixture of compounds.

Many workers in an office building complained about IAQ. No moisture damage was foundin the offices, which were, however, painted and carpeting was changed. Ventilation ductswere cleaned and the supply and exhaust air vents were installed in every room. Shortly afterthe repair the workers developed symptoms. A thorough survey of IAQ including microbesand particles and volatile organic compounds was conducted twice after the repair. Betweensurveys the rooms were cleaned for 2 months twice a week with more effective practices thanbefore.

Tracer gas sorption in and permeation through building materials influence tracer gas ventilationmeasurements. Therefore, it is important to have knowledge about these processes.The permeation of three commonly used tracers (SF6, N2O and the PFT C6F6) through untreatedgypsum board has been experimentally investigated. The result shows that all three tracers diffusereadily through this material (diffusion coefficients in the order of 1 10.-6 m2/s). Caution shouldtherefore be exercised when using tracer gas measurements in rooms with walls of gypsum boardor other porous materials.

The aim of this study is to analyse the impact of volatile organic compounds emissions from asolid flooring material on the concentration field in a ventilated room. A field study has beenconducted in the CSTB experimental house MARIA. Measurements were performed in a testroom recently equipped with a flooring material made of pine wood and under controlledventilation conditions. a-Pinene was selected as tracer from flooring VOC emissions. Velocityand temperature fields are measured in different points of the room.

The aim of the study was to find out if the location of material has effect onmicrobiological findings. Material samples (n = 735) were taken from the buildingswith susceptible moisture damages. Viable fungal spores and bacteria were analysedfrom paperboard, insulation material and wood samples from inner and outer parts ofconstruction. Microbial biodiversity was largest in inner parts of construction. In wallcavity, insulation material had largest microbial diversity.

Especially in new buildings we could find striking concentrations of MVOCs and we couldnot localize mould damage. We first supposed that some MVOC components are not specificfor microorganisms but normal VOC from new materials. But very often the mould dogmarked walls and floors spacious in new buildings where we detected MVOC in the indoorair.To obtain information if new materials contain microorganisms, we analysed gypsumboard, Styrofoam and mineralic insulation material for fungi and bacteria that we purchasedin three different hardware stores.