Volatile and semi-volatile organic compounds as well as particulate emissions of candles were investigated in a total of 3 independent studies. A first screening study, conducted at the laboratories of TNO Quality of Life, the Netherlands, aimed at establishing a candle emission testing protocol in a small emission test chamber with a volume of 2.2 m3 (‘‘small chamber study’’). Two subsequent studies were conducted at the laboratory of Air Quality Sciences (AQS), an ISO 9001:2000 registered Indoor Air Quality Laboratory, in normal room size emission chambers with a volume of approximately 26 m3. The first study at AQS (‘LCS1’) investigated the same compounds emitted from candles in the ‘small chamber study’ (‘SCS’) allowing a direct comparison of the results obtained. The second study at AQS (‘LCS2’) investigated different VOCs including semivolatile PAH, PCDD and PCDF. The large chamber investigations also determined candle emissions of particulates characterized as PM10 and PM2.5. The contract laboratories were chosen on the basis of
their substantial experience with the measurement of VOC, SVOC and PM in chamber emission studies using existing ISO- and ASTM standards (ISO, 2006, ASTM, 2001). The methodology to measure candle emissions largely followed the frame protocol described later by Petry et al. (2013) with regard to the experimental set-up,study protocol, meteorological conditions with regard to chamber temperature and relative humidity at candle ignition and analytical methods used to measure VOC emissions from candles according to existing ISO- and/or ASTM standards.