I have been using Panasonic inline whisper fans for about two years. They are very quiet and come in a range of capacities and types. I read about them on the Large Format page and decided to give them a try. The only sound you hear is the sound of wind in the four inch duct.. I hope they have an Australian importer/distributor. The air coming into my darkroom goes through a high grade furnace filter which I can clean as needed.Originally Posted by Nige
Here is a link to the US source I used and product description http://www.rewci.com/panwhisvenfa.html
Panasonic inline whisper fans are more expensive than the hardware store type bathroom fans, but the hours of peaceful quiet work in the darkroom, or the ability to hear your music without mechanical noises, have been well worth the price.