Determination of time- and size-dependent fine particle emission with varied oil heating in an experimental kitchen

Particulate matter (PM) from cooking has caused seriously indoor air pollutant and aroused risk to human health. It is urged to get deep knowledge of their spatial-temporal distribution of source emission characteristics, especially ultrafine particles (UFP<100nm) and accumulation mode particles (AMP 100-665nm). Four commercial cooking oils are auto dipped water to simulate cooking fume under heating to 265°C to investigate PM emission and decay features between 0.03 and 10μm size dimension by electrical low pressure impactor (ELPI) without ventilation. Rapeseed and sunflower produced high PM_2.5 around 6.1mg/m³, in comparison with those of soybean and corn (5.87 and 4.65mg/m³, respectively) at peak emission time between 340 and 460sec since heating oil, but with the same level of particle numbers 6-9×10⁵/cm³. Mean values of PM_1.0/PM_2.5 and PM_2.5/PM₁₀ at peak emission time are around 0.51-0.66 and 0.23-0.29. After 15min naturally deposition, decay rates of PM_1.0, PM_2.5 and PM₁₀ are 13.3%-29.8%, 20.1%-33.9% and 41.2%-54.7%, which manifest that PM_1.0 is quite hard to decay than larger particles, PM_2.5 and PM₁₀. The majority of the particle emission locates at 43nm with the largest decay rate at 75%, and shifts to a larger size between 137 and 655nm after 15min decay. The decay rates of the particles are sensitive to the oil type.