Emissions from building products can considerably impair the quality of indoor air. The AgBB scheme is employed to evaluate the emissions of volatile organic compounds (VOC) from building products. The hygienic evaluation according to the AgBB scheme requires product-specific measuring procedures.
These are available for a range of products. They have been validated in co-operation with several research and testing institutes and have been included in the criteria for awarding the Blue Angel ecolabel.
The evaluation is, however, stricter and generally has lower limits. VOC emissions and odours can cause health problems so testing using sensors is an important element in the evaluation of building products and has – for reasons of precaution – been set down in the AgBB scheme. The main goal of the project was to derive a method of evaluation using sensors and limits for awarding the Blue Angel and for the AgBB scheme. Based on the research conducted (see Chapter 5 Results and Discussion), perceived intensity and hedonics were suggested as a suitable Evaluation method. The derivation of limits for the evaluation using sensors on the 28th day was effected in the present study through the additional questioning of the test subjects on the reasonability of a sample.
For the Blue Angel, there could be different limits of perceived intensity and hedonics for each group of products. A preliminary suggestion for possible limits – for all product groups – is a perceived intensity of 7 pi (5 pi + 2 pi as confidence coefficient, Chapter 5.1.5) and -1 (0+/-0.8, rounded to -1) for the hedonic value.
Since semi-volatile organic compounds (SVOCs), including biocides and polychlorinated biphenyls (PCBs), occur indoors as well as outdoors, air sampling adsorbents and measuring methods for all these compounds are indispensable. This paper presents the initial steps in the development of such a method, the aim of which is the analysis of selected compounds in the above-mentioned classes using low air sampling volumes and air-exchange rates close to zero, as is common in museum showcases. For measurements under easily controlled conditions, a micro-chamber system was used at different temperatures. A surface modified styrene divinylbenzene (SDVB) polymer was selected as the air sampling adsorbent for the elution experiments. After successfully performing pretests using the micro-chamber system with target compound solutions, the emissions of these compounds from self-soaked wood samples and con-taminated wood samples were investigated for method development.
The aim of this study was the development of a low volume air sampling strategy for biocides and polychlorinated biphenyls (PCB) at low air change rates in modern, air-tight showcases as they are present in museums. Lindane, pentachlorophenol, dichlofluanid, tolyfluanid, isodrin, p,p-dichlorodiphenyl trichloroethane and permethrin were the biocides and PCB 28 and PCB 153 were the PCBs studied, all of which are semi volatile organic compounds (SVOC). Their occurrences in the museum environment originate from various sources e.g. preventive treatment of organic exhibits or organic building materials. Exhibits are long-term exposed to these pollutants due to storing in showcases or other storage equipment at low air change rates. To achieve air sampling under the aforementioned conditions the influences of temperature, air circulation, air change rate and relative humidity on the emission behavior of the selected biocides and PCBs had to be determined. This was carried out with pre-soaked wood samples in low volume air sampling experiments using 27 L test showcases and 23 L and 24 L emission test chambers and also diffusive sampling with glass as the sampling material.
EN 16516 sets specifications for the determination of emissions into indoor air from construction products. Reliable, accurate and International System of Unit (SI)-traceable measurement results of the emissions are the key to consumer protection. Such measurement results can be obtained by using metrologically traceable reference materials. Gas-phase standards of volatile organic compounds (VOCs) in air can be prepared by a variety of dynamic methods according to the ISO 6145 series. However, these methods are not always applicable for semi-VOCs (SVOCs) due to their high boiling point and low vapour pressure. Therefore, a novel dynamic gas mixture generation system has been developed. With this system gas-phase standards with trace level VOCs and SVOCs in air can be prepared between 10 nmol mol−1 and 1000 nmol mol−1. The VOCs and SVOCs in this study have normal boiling points ranging from 146 °C to 343 °C. Metrologically traceable reference materials of the gas-phase standard were obtained by sampling of the VOC gas-phase standard into Tenax TA® sorbent material in SilcoNert® coated stainless steel tubes. Accurately known masses between 10 ng and 1000 ng per VOC were sampled. These reference materials were used to validate the dynamic system. Furthermore, the storage and stability periods of the VOCs in the reference materials were determined as these are crucial characteristics to obtain accurate and SI-traceable reference materials. In a round robin test (RRT), the reference materials were used with the aim of demonstrating the feasibility of providing SI-traceable standard reference values for SVOCs for interlaboratory comparison purposes. Based on the results from the validation, the storage and stability studies and the RRT, gas-phase standards and reference materials of VOCs and SVOCs with relative expanded uncertainties between 5% and 12% (k = 2) have been developed. These reference standards can be used as calibrants, reference materials or quality control materials for the analysis of VOC emissions.