I assume weed eaters are already being regulated by the latest CARB emissions requirements, same with bee blowers. I suppose you could better control the A/F ratios in a smoker to minimize CO. Maybe we need smokers with a little micro controlled fan to puff air in and an O2 sensor for feedback?
I have a 92 year old neighbor who drives some old manual tractor in my towns parade down main street every year. He’s a nice old man, but STILL, it is wise for a 92 year old guy to be driving the farm version of a tank down main street just feet from kids? Between the old guy and the old tractor and the manual tranny, your odds of something breaking goes way up.