Sometimes I get questions from buyers about whether it’s ok to just have a recirculating kitchen range hood. I always say external venting is critical to good health. Not only do most building codes require new builds to have venting, but there’s a lot more information out there today about the dangers of gases coming off of gas ranges from just the act of cooking food.
The below screenshot is the amount of VOC's in my living room when I was cooking some ground beef on the stove to make tacos for the kids. I always use the back burner so it's closer to the wall and doesn't smoke up the kitchen, and I have my 300 cfm ventilation hood on high. My hood is ducted via an 8’ round duct that I installed myself, venting directly out the side of the kitchen, a total ducting run of about 8 feet. The air quality sensor is in the farthest corner of the living room, as far as I can get it from the kitchen, which is accessible through a standard sized doorway. Note how many hours it took for the VOC level to come down after I cooked and spiked it.
There's always a spike whenever I cook, which is why I'm planning to install a much more powerful ventilation hood soon, as well as put up stainless steel-covered walls on the sides of the stove to go up from the stove to the ventilation hood. Note, it’s important to have an expert licensed contractor analyze your home situation to avoid creating dangerous backdrafts in any gas burning appliances you may have in the home. The most common mistake is having a powerful ventilation system which sucks air back down your basement chimney so all the combustion gases from your water heater and heating system get pulled into your living area. Be careful!
Here's the day after when we made Japanese pork curry:
And lastly, below is the reading when I stir-fried H-mart pre-marinated bulgogi in a cast iron pan on the back burner, with stir fried bok choy in a steel wok on the front burner. Note that none of my pans have teflon or non-stick coatings, they’re all cast iron or uncoated steel, so the VOCs are not from any of those plastics.