When you plug a Exaust fan in and hear it ,You will most likely think WTF,it's too loud.But don't go on that ,it will become 70% more Quiet,once you connect to the Filter ,use a belt strap,the ones with Foam on the inside So once it's tight.No chance of air leaks of smell.Then make sure the duct is fitted via the same method tight no leaks ,then to a air vent that will push the air out the room.I use vortex,and I have had them years ,they are great fans.I use a 12 inch out let, 6 inch inlet ,both run 24/7 .You can get a speed dial, if you think it may be too much for your room,but I use two 600 hps cool hoods and a hps bulb,has a swinger that I drop around the room in winter,when temps are lower.But normally just two plants under 2 lights ,just grown big.I think you have seen my grows,so you will know the set up.A good tip is get a converter from the fan that takes larger ,duct this will make it less noisy.I use a converter,from mine that makes it take 8 inch duct just because it took less room up .If your using say 2 LEDs with built in fans then I would go with something like a 4/6 inch out let ,same size in .Not much heat from them so no need for big fans .Inlet have it pulling air from a void or window,then duct running down center of grow room,with holes punched in the side for even spread of fresh air.if you have the room .But ally's have inlet at ground level,out let has high in the room has possible,for them to work most effective.
Good Luck
Tyke