Does anyone know of a good air filter (portable type unit) that will work to remove chemicals from a darkroom? My darkroom is in my basement, so I can't connect to a window. I'm having problems with allergies from the chemicals.

-- Sharon Bussert (sharon@bussert.com), April 18, 1999

Answers

I don't think what you are asking for is as feasible as you think. In order to "remove" the chemicals from the air, you will have to have a chemical filter, not just an air filter. I've seen them in the Silicon industry, but I've never seen them available for "home" use.

Why can't you get access to a window? you can use a dryer vent duct and vent to extract the air to the exterior... I've seen dryer ducting go more than 30 feet successfully.

-- Andy Hughes (andy@darkroomsource.com), April 19, 1999.

A safety supply dealer can sell you a mask which holds different cartridges for use with different chemicals. I agree with the last answer(Ducting your exhaust fan) but if you can't, try this.

-- tim ruck (auroraphoto@compuserve.com), April 20, 1999.

The problem is with life span and ability to capture. The typical "chemical" filter is activated charcoal. It will NOT capture and hold all chemicals, and how well it performs for any one chemical will not tell you how well it performs against another chemical. The filters in most table top or household setups has a very small amount of activated charcoal and a very limited life span. I have to do some research to see how well activated charcoal does against typical photo chemicals.

WRT a respirator, the same things as above apply. And you should only use a respirator with chemicals with good "warning" properties. That is, those who have a recognizable odor at levels well beow the level causing trouble. Typical photo chemicals do not meet this requirement. So you really don't know whether the rtridges are actually doing any good until you have a reaction.

Best case is to duct the air out. There is just about always a way to get the air out of the darkroom and out of the space. Do watch that as the duct gets long, the actual air moved goes down due to friction losses in the duct. You should plan on a REAL 10 air changes per hour, and take the air from near the chemical trays.

-- Terry Carraway (TCarraway@compuserve.com), May 20, 1999.