bath fans and range hoods

[mlnk]

Does the NEC allow connecting vent fans to lighting circuits? What if the fans are over 300 watts or 1/8 hp? I know that if you are running one 20 amp circuit to a single bath, you can include the fan, (unless it is a heater fan using over 10 amps). I nowadays run all bath, laundry fans on a separate circuit to avoid light dimming. I generally run a separate 12-2G to the range hood because it may become a MW unit in the future, but connect it to the 15 amp fan circuit. Typical MW hood = 1800 watts

 

[kwired]

Does the NEC allow connecting vent fans to lighting circuits? What if the fans are over 300 watts or 1/8 hp? I know that if you are running one 20 amp circuit to a single bath, you can include the fan, (unless it is a heater fan using over 10 amps). I nowadays run all bath, laundry fans on a separate circuit to avoid light dimming. I generally run a separate 12-2G to the range hood because it may become a MW unit in the future, but connect it to the 15 amp fan circuit. Typical MW hood = 1800 watts

Typical bath exhaust fan is not even close to 300 watts or 1/8 hp.

1/8 hp fan will move pretty good chunk of air and you are looking at high volume air movement applications where it is intended to remove smoke, dust, other fumes in short time.