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

Figures & data

Table 1. Characteristics of the range hoods evaluated in the study.

Range hood ID	Model	Description	Dimension (cm)			Screen filter number	Retail price (CAD)	Speed setting	Manufacturer specified airflow (L/s)	Measured airflow (L/s)
			Width	Depth	Height
A	Broan-Nutone RL6100F	Basic	76	46	15	1	n/a	1	85	75
B	Broan-Allure QS130SSN	Energy star	76	51	18	2	$211	1	52	36
								2	104	84
C	Bosch DUH30252UC	High performance	76	51	15	2	$550	1	n/a	69
								2	n/a	94
								3	n/a	120
								4	189	146

Figure 1. Contour plots of mean background-removed particle concentrations and size distributions measured under Fan Off After Cooking test condition, from 15 min before cooking to 3 h after cooking, by range hood flow rate. The time of 0 represents the end of cooking.

Figure 2. Average particle peak concentration as a function of particle size at each range hood flow rate, measured under Fan Off After Cooking test condition. The error bars represent standard errors of the mean based on replication tests. Only the plus side of the error bars is shown to minimize overlapping. The x-axis is logarithmic.

Table 2. The size-resolved UFP peak reduction with six range hood flow rates.

Particle diameter (nm)	Mean estimate of peak reduction (%)
	36 L/s	69 L/s	75 L/s	84 L/s	120 L/s	146 L/s
10–13	15	60	41	67	89	99
13–18	21	52	26	58	81	98
18–24	35	33	17	44	78	98
24–32	30	39	23	49	78	98
32–42	25	44	30	57	78	98
42–56	20	50	38	63	80	98
56–75	19	52	40	64	80	98
75–100	21	49	29	60	78	98
100–133	23	49	20	53	77	98
133–178	16	65	27	53	82	98
Total particles^a	25	44	30	58	79	98

^a The total particle concentration is the sum of size-resolved particle concentrations (10–178 nm).

Figure 3. The top panel presents the cumulative exposure to total particles due to cooking over the entire monitoring period, measured under Fan Off After Cooking test condition. The x-axis represents the time relative to the end of cooking (t = 0). The bottom panel shows the time-integrated exposure over the cooking period and each hour after cooking ended, measured under Fan Off After Cooking test condition.

Figure 4. A comparison of mean deposition rate of the total particles and the mean air exchange rate at each range hood flow rate, measured under Fan Always On test condition. The flow rate of 75 L/s was excluded due to large uncertainties.

Figure 5. The source strength distribution for particles in the size range of 10–178 nm due to cooking on a gas stove. The error bars represent the propagation of standard errors that took into account uncertainties from estimated particle decay rate and peak concentration.