Effect of venting range hood flow rate on size-resolved ultrafine particle concentrations from gasstove cooking

Cooking is the main source of ultrafine particles (UFP) in homes. This study investigated the effect of
venting range hood flow rate on size-resolved UFP concentrations from gas stove cooking. The same
cooking protocol was conducted 60 times using three venting range hoods operated at six flow rates
in twin research houses. Size-resolved particle (10–420 nm) concentrations were monitored using a
NanoScan scanning mobility particle sizer (SMPS) from 15 min before cooking to 3 h after the cooking
had stopped. Cooking increased the background total UFP number concentrations to 1.3
103 particles/
cm3 on average, with a mean exposure-relevant source strength of 1.8
1012 particles/min.
Total particle peak reductions ranged from 25% at the lowest fan flow rate of 36 L/s to 98% at the
highest rate of 146 L/s. During the operation of a venting range hood, particle removal by deposition
was less significant compared to the increasing air exchange rate driven by exhaust ventilation.
Exposure to total particles due to cooking varied from 0.9 to 5.8
104 particles/cm3h, 3 h after cooking
ended. Compared to the 36 L/s range hood, higher flow rates of 120 and 146 L/s reduced the
first-hour post-cooking exposure by 76% and 85%, respectively.