QUOTE(Supreme1394 @ Sep 19 2013, 06:28 PM)
If you install kitchen hoods, it helps to filter smell, oil vapour and cooking gas but after awhile, thick layers of sticky oil residues accumulate in the hood and that requires frequent cleaning. Germs grow in the duct too, and then travel to the external parts and may even drop into the cooking pot. You need to replace the duct itself but meanwhile, you may be cooking up worms in your dishes.
Commercial sellers talk only about the need to clean the hood but mention nothing of what happens during the intervals. Steams can't kill these organisms but irritate them to drop. Just read up wikipedia on hood cleaning, use basic knowledge to read deeper and figure out the unspoken truth. Apply this thinking skill to all other things. Then decide: can you do without these commercial products?
Additional note:
Standard kitchen top is around 32" to 34" high and the hood is about 2 ft above it to be effective at suction. This brings to a total of 54" (4.5 ft.). Anyone 5 ft tall and above can be hit if you bend your head forward while cooking. Commercial advertisements seek to create an untrue picture that everyone has accepted these without any problem, the so called 'in-thing'. If you are not for them, you haven't reached the standard yet. So most people keep the mishaps to themselves thinking that they are inapt at using them.
With hood, u get germs and worms in your food.
Without it, then cook under the sky? Flies and birds fly past aso....how?
If cook indoor without hood, very messy leh.
Ya, cleaning the hood is important. Frequent cleaning that is. And also do keep the hood switched on for a while even after u finish cooking.
I'd rather put the hood higher than to accidentally hit it. If put too low, how to use bigger pots or wok over the stove?

there's a standard distance recommended ..I follow that.