I installed a high CFM hood for my stove, mainly for searing on cast iron and dealing with the smoke, but I wonder if this helps with the NO2 exposure mentioned in the article. A high CFM hood was something I never knew I needed until I had one. It's fantastic.
Maybe. Probably. The article is a bit mixed on range hoods and doesn’t look at high CFM ones specifically, but it stands to reason it would help.
“ We found that an outside-venting range hood reduced peak NO2 concentrations in some cases (Fig. 3B) but that some outside-venting range hoods are ineffective at reducing NO2 concentrations (Fig. 3C). Across a subset of five randomly selected homes, we found that outside-venting hoods reduced hour-averaged kitchen NO2 concentrations by between 10 and 70% (mean reduction in concentration = 35%, n = 5; fig. S15). This result is consistent with prior work assessing the efficacy of installed range hoods, which found that most hoods operating in homes have capture efficiencies well below 70%”
Addresses typical range hoods, not necessarily high CFM quality ones.
“ people with a 75% capture efficiency outside-venting hood who use it every time they cook are exposed to 70% less long-term stove-attributable NO2 than average. The effect on long-term stove-attributable NO2 of opening and closing windows (one window modeled in the kitchen and at least three additional windows, opened or closed all at once; see Materials and Methods) was comparable to the average benefit of using a range hood (Fig. 5).”
Implies higher quality (capture >75%) range hoods help significantly but so does opening a window.
Efficacy is also going to vary with usage. I've got a 900CFM fan, but I can still smoke up the kitchen pretty badly if I sear on the front burner, even with the fan on high. However, if I use the back burner, even with the fan on low, the air stays pretty clear.
Are you sure it's really a 900CFM fan? A lot of cheap fans on amazon claim they are high CFM and when you look at components, are like 400 at best. High CFM fan will run you at least $2k to start.
Yes, it probably helps, especially if you crack a window. The article claims 3000 sq ft dwellings do better than 800 sq ft dwellings -- this will be entirely due to the concentration of the gases. A hood that expels interior air and draws in outside air can't hurt.
