Ultrafine particle emissions from cigarette smouldering, incense burning, vacuum cleaner motor operation and cooking

Combustion activities such as cigarette smouldering, incense burning and cooking are important sources of particulate matters (PM) in indoor environments. Vacuum cleaning contributes to the non-combustion-related sources of PMs. In this study, we investigated the rates at which ultrafine particles (UFPs) are emitted from cigarettes, incenses and vacuum cleaners in a small test chamber. UFP emission from cooking was obtained by conducting experiments in a residential kitchen. Particle number concentrations and size distributions from these sources were measured using a scanning mobility particle sizer (SMPS) and the UFP emission rates were then determined using a material balance approach. The mean UFP emission rates of cigarette smouldering and incense burning were found to be 3.36 ± 0.34 and 0.44 ± 0.33 × 1011 particles min-1 in terms of the number emission rate, or 22.78 ± 1.21 and 3.48 ± 2.98 × 1015 nm2 min-1 in terms of the surface area emission rate, respectively. Vacuum cleaner motor operation and cooking showed high variations in UFP emission, in the ranges 0.013-0.066 and 4.70-148.29 × 1011 particles min-1, respectively. A database of emission rates for UFP sources can be compiled, which will be useful in estimating the UFP concentration and subsequent human exposure.