Comparison of cooking emissions mitigation between automated and manually operated air quality interventions in one-bedroom apartments

Abstract

We implemented a crossover study design exposing 15 participants to two indoor air quality conditions in the Well Living Lab. The first condition, the Standard Control Condition, resembled the ventilation and air supply of a typical home in the USA with a manually operated stove hood. The second condition, Advanced Control, had an automated: (i) stove hood, (ii) two portable air cleaners (PAC), and (iii) bathroom exhaust. The PM_2.5 sensors were placed in the kitchen, living room, bedroom, and bathroom. Once the sensor detected a PM_2.5 level of 15 μg/m³ or higher, an air quality intervention (stove hood, PAC or bathroom exhaust) in that space was activated and turned off when the corresponding PM_2.5 sensor had three consecutive readings below 6 μg/m³. Advanced Control in the overall apartment reduced PM_2.5 concentration by 40% compared to the Standard Control. The PM_2.5 concentration difference between Advanced and Standard Control was ~ 20% in the kitchen. This can be attributed to using the stove hood manually in 66.5% of cooking PM_2.5 emission events for 323.6 h compared to 88 h stove hood used in automated mode alongside 61.9 h and 33.7 h of PAC use in living room and bedroom, respectively.

Figure 1

Residential module layout.

Figure 2

Data completeness: (a) PM_2.5 sensors, (b) stove hood data. White squares indicate no participant in the study on that day.

Figure 3

Hourly average concentrations for the Standard and Advanced Control Conditions in the WLL apartment. Lines represent the hourly average PM_2.5 concentration for all participants, and bands represent the 95% confidence interval of the hourly average.

Figure 4

Hourly average concentrations for the Standard and Advanced Control Conditions in the kitchen. Lines represent the hourly average PM_2.5 concentration for all participants, and bands represent the 95% confidence interval of the hourly average.

Figure 5

Comparison of PM_2.5 concentrations in the kitchen under Standard and Advanced Control within 15 min, 30 min, and 60 min after cooking started for all participants. The boxes represent data within 1st and 3rd quartiles; the whiskers represent data within 1.5 times the interquartile range of the 1st and 3rd quartiles; the line in the box represents the median.

Figure 6

Examples of Standard and Advanced Controls for stove hood. x-axis is time, y-axis on the left side shows PM_2.5 mass concentration, on the right side in fan speed. Line represents status of the stove hood and the dot represent PM_2.5 mass concentration.

Figure 7

PM_2.5 concentrations in the kitchen during (a) 15 min after cooking started, (b) 30 min after cooking started, (c) 1 h after cooking started. Participant IAQ16, although depicted in this figure, dropped out of the study. Since we had an incomplete data set for IAQ14, all data was removed from the previous analysis. In the current figure, we showed the results as an illustration.