My darkroom is my utility room and it has only one window(sealed) and the door. I can turn on the furnace fan and thus circulate some air, but not much. I would like to tone my prints but I am afraid I don't have enough ventilation for this toner. Any thoughts, and would a small fan help???

-- Larry Mankin (mankin.larry@epamail.epa,gov), March 17, 2000

Answers

Larry if your concerned about the ventilation in your utility room, can you tone your prints in another room with better ventilation, since toning can be done in full daylight?

I would also add that good ventilation is important anytime your in a small enclosed room with any chemicals. Fixer fumes aren't exactly great for your lungs either. Of course I realize that with home darkrooms you don't always have a choice. Darkroom ventilation fans that are light tight is one other solution.

-- Paul Swenson (paulphoto@humboldt1.com), March 17, 2000.

Larry, Fumes from selenium toner are mostly ammonia and not all that harmful (they can be highly unpleasant though!). With selenium it is more important that you avoid skin contact, especially with the concentrated solution in the bottle. Working solutions are much less concentrated and present a much smaller risk. Having said that, I would also recommend that you provide some kind of ventlation for your darkroom, be it switching on the furnace fan or opening the doors/windows (is there any way you can lightproof your window and still have it open when you need it?) when you don't absolutely need things totally dark. Repeated and long term inhaling of the acid/ammonia/etc. fumes from darkroom chemicals is simply not a good idea no matter how "safe" they are supposed to be. Anything you can do to reduce exposure is probably a good idea. I've insalled an exhaust fan over my darkroom sink (just a cheapie with 6 feet of exhaust hose coiled around itself in the attic to make it lightproof) and I throw open doors and windows as soon as the film/prints have been in the fixer for a minute. Odorless fixers (Kodak F-6 formula, or Zone VI fixer) help too. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), March 18, 2000.

Ammonia is an irritant to the mucus membranes and the time weighted average for 8 hrs is 50ppm. Not a good idea to use selenium toner in an enclosed room without good ventiation. Go outside to do your toning. You can tone in the sunlight. James

-- james (james_mickelson@hotmail.com), March 19, 2000.

If you have a fan in the kitchen or bathroom, either is fine for the smell. What is important, for the sake of the print, is trying to find somewhere with GOOD light. Whatever looks good under weak tungsten or flourescent light is sure to NOT have the look you want viewed in any other room/source. Kitchen for ventilation and sunlight works for me...

-- shawn gibson (SeeInsideForever@yahoo.com), March 20, 2000.

James,

The good thing about ammonia, is that you will be driven from the room at levels well below 50ppm. Most people are sensitive enough to it, to leave at between 5 and 10 ppm.

The problem comes with large, fast releases, like a leaking ammonia refrigeration unit.

BUT, any darkroom chemicals require good ventilation while using. For general ventilation, 6 air changes per hour is minimum. To calculate this, figure out the room volume (height time length times width) and divide by 10. That is the minimum air flow through the fan. Also remember to work, you need a source of makeup air that will easily flow the same amount of air or more.

-- Terry Carraway (TCarraway@compuserve.com), March 20, 2000.

The first thing I learned in chemistry was that food and chemicals just don't go well together. So ventilation issues aside, I would be reluctant to use anything as toxic as selenium toner in the kitchen, even if it has a nice window and water is easily available, because even when working carefully, you can't always make sure there is no contamination.

-- Thomas Wollstein (thomas_wollstein@web.de), March 20, 2000.

Good point, Thomas. I'm there out of necessity, but given what you noted I wouldn't recommend it to anyone either. Sometimes my brain works a little behind my heart...shawn

-- shawn gibson (SeeInsideForever@yahoo.com), March 20, 2000.