darkroom ventilation

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My darkroom is about 10' x 10'. I have a small Doran fan/ vent that just doesn't work all that well. I decided to try my air purifier. Its not just any air purifier. Its an exceptional machine that destroys odors, its an Alpine if anybody is familiar with it. I'd say it takes out 90% of the odor. There is a little amber light inside it, and sometimes a little green light comes on. It does not effect my printing, but I don't know if I can block this light when proccessing my film. I was just wondering what everyone who proccesses black and white here does. Calumet sell a ventilator called Vent Axia. Does anyone have experience with this. I have a window in my darkroom. I built a frame out of wood the size of the window and covered it with light tight plastic, attached to the frame was the Doran fan. The frame is easily removable, so I could attach another type of fan/ ventilator if anyone has any suggestions. I admit my Doran fan is a small one, maybe meant for a room 6'x8', but do they work that well at all, anyway? Thanks.

-- Raven (mtand13@netreach.net), July 22, 2000


I think the most important aspect of darkroom ventilation is having a vent that allows air to come into the darkroom. A fan cannot remove air from a room that does not have an air intake of equal size as the fan. Once I put a light-tight vent in, all my problems with darkroom odors went away.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), July 22, 2000.

Raven: I use a small through-the-wall vent fan in my darkroom. One of the things I discovered is that you also need another vent to let air into the darkroom. If you use the exhaust vent only, with no air inlet, you can actually create a bit of vaccuum in the room which seems to increase the amount of fumes from the trays. With a vent on the other side of the room, you get a cross flow of air which seems to help. The additional vent doesn't need a fan. My system isn't perfect, but it helps a lot.

Regards, Doug.

-- Doug Paramore (dougmary@alanet.com), July 22, 2000.

Sorry, I guess I wasn't clear. I have a small fan and also a vent. They are placed exactly where the directions said. The vent is ground level, and the fan is on the other side of the room, about shoulder level, so the fumes are being pulled away from me. Its just that the fan doesn't remove much of the fumes. Thanks.

-- Raven (mtand13@netreach.net), July 22, 2000.

Someone can correct me if I'm wrong, but I believe the recommended amount of room air changes/hour is at least 10, and up to 20 for a smaller room. Figure out your cubic footage & Make sure your fan has the capacity you need-with an adequate fan and intake you simply shouldnt have odor problems, assuming that the chemicals are BETWEEN you and the exhaust, which it sounds like they are. I dont know that a purifier wouldnt work, but I think a good exhaust fan is a better idea. If the purifier is recycling room air rather than venting it OUT, then you might not have enough fresh air coming in the intake vents

-- Wayne (wsteffen@mr.net), July 22, 2000.

I bought a standard bathroom exhaust fan, built a wooden box to make the vacuum work, and connected it to the darkroom via a piece of flexible dryer duct. Works great and was really cheap.

-- Chris Hawkins (peace@clover.net), July 22, 2000.

You also might think about different chemicals. Kodak's fix and stop baths are pretty strong. Consider getting Photograde Citric Acid for a stop bath or a company called Sprint (out of RI) sells photochemicals. Their stop bath smells like vanilla and their fix is almost odor free. Ilfords isn't that bad also but it is important to have the right amount of air exchange just the same. Cheers

-- Scott Walton (scotlynn@shore.net), July 22, 2000.

I do have it set up so the fan is not pulling the fumes past where I am, however, I do use Kodak Indicator stop bath, and Polymax fixer. I do recall now Ilford fixer not being quite as strong, however, now that I see it could be the chemistry too, if anyone can give me feedback on other brands. I will check the above too. Thanks so much.

-- Raven (mtand13@netreach.net), July 22, 2000.

I really appreciate that info on Sprint, Scott. I checked out their web site, and I'm looking foward to purchasing their chemistry. Problem solved. Thanks again.

-- Raven (mtand13@netreach.net), July 22, 2000.

If you don't mind measuring & mixing chemicals, F6 and F24 might be another solution. Both are easy on the nose. I use F24 most of the time. It is easy and relatively inexpensive to make, has no hardener and has almost no odor. The formulas are both listed in the Ansel Adams book, The Print.

-- Steve Barth (wsbarth@networld.com), July 23, 2000.

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