I'm not surprised about the gas stove pollution, but am surprised at how ineffective kitchen fans are. I got an air purifier with a sensor on it. It's about 8 f

I'm not surprised about the gas stove pollution, but am surprised at how ineffective kitchen fans are. I got an air purifier with a sensor on it. It's about 8 feet away from the kitchen and it always goes on a few minutes if I switch any of the burners to a high setting. This happens even when I have the stove fan setting on high. These are suppose to suck the bad air out, but don't seem to do a good job at it.