Home darkroom - fume flammability?

zeddicus

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Hi all,

Long time reader, first time poster :)

I am in the initial stages of building a home darkroom in a spare bathroom. The space does not have a window however it does have an overhead fan exhausting into the ceiling space.

Two questions:

1. Are the fumes from b&w or colour development process flammable? and;
2. What problems can you forsee if I was to exhaust fumes from development into the shared ceiling space?

We have a baby on the way in May so I'm somewhat concerned about venting into an enclosed space, especially given the bathroom is an ensuite to baby's room.
 
Unless you're doing collodion photography or using solvents regular chemicals like developers and fixers aren't flamable. As to any effects on your child you should contact the manufacture for information.

Usually developers have no odor and Formulary FT4 and FT5 fixer have little to none if mixed with distilled water. Regular powdered fixer (sodium thiosulphate) was once used to treat skin fungus and the active ingredient is used to treat cyanide poisoning. It do have an unpleasant odor to many people. Acid stop has an unpleasant smell to most so I'd use water to stop.

There are some environmentally safe chemicals now you might explore.
 
If you are developing film in a light-tight canister, load the film in the dark bathroom, then pour your chemicals elsewhere away from the baby's room.
 
Not flammable.

Assuming you mean a print darkroom, not just film developing: How hard would it be to exhaust to the outside? When you look at Material Data Safety Sheets (MSDS), you'll see all sorts of parts per million and such but no simple answers to your concern. If I had a child I would simply not take the risk. Vent to the outside, pure and simple.

There are so many unknowns in the effects of chemicals. Synergies, time, accumulations, etc. People get sensitized and develop allergies over years. You don't know what other exposures your child may have in their life. You may change your techniques down the road and be using chemicals that are more hazardous. Just do it right from the beginning. Annoying, yes.
 
In my decades of having my own B&W darkroom the only flammable chemical that I had in there was some film clearer (usually Edwal's). Flammable vapors being sucked into the exhaust and past a hot and possibly sparking motor will not be an issue in a normal darkroom.

The hazards with normal B&W chemicals are limited to toxins and extreme irritants. The former are mostly toners and, to a lesser degree, some developing agents (e.g. Metol). The latter are the more concentrated liquid stop and fixers before they are diluted to working strength. Care should be taken to child-proof the storage location for all chemicals, household cleaners as well.
 
Not flammable.

Assuming you mean a print darkroom, not just film developing: How hard would it be to exhaust to the outside? When you look at Material Data Safety Sheets (MSDS), you'll see all sorts of parts per million and such but no simple answers to your concern. If I had a child I would simply not take the risk. Vent to the outside, pure and simple.

There are so many unknowns in the effects of chemicals. Synergies, time, accumulations, etc. People get sensitized and develop allergies over years. You don't know what other exposures your child may have in their life. You may change your techniques down the road and be using chemicals that are more hazardous. Just do it right from the beginning. Annoying, yes.

Point well taken, thank you. I think I'll try to convert my office space instead. Much more room there as well :)
 
Welcome to Rangefinder Forum.
Do you smoke? If you do, please don't when you are doing darkroom work.

Thanks for the welcome Bill. As for smoking, not for almost a decade now.


Never read or heard of a fire caused by photography chemicals. You, more than likely, have other products where you live that can be a problem with a fire. Do you have a fire extinguisher? What classes of fires will it extinguish? This is what I did when I served in the U.S. Navy.

I was mainly asking because I don't yet know what chemicals I need for film and prints. It's probably one simple google away. Once I figure that out I will of course consult the relevant MSDS.

Our house is well stocked; fire blanket and 4.5Kg drychem AB(E) extinguisher as well as several combination fire and CO alarms.

I gave up film developing and printing when my wife and I had children. We were too busy!

I've not developed film or made prints since high school and I have long since forgotten everything I knew about it. I'm hoping to make time to learn again :)
 
I have no exhaust fan in my space, have not blown myself up so far.

On the other hand, I am not very careful (no gloves when mixing chemicals, etc), so may be dying in slow motion. ;-(

Randy
 
I have no exhaust fan in my space, have not blown myself up so far.

On the other hand, I am not very careful (no gloves when mixing chemicals, etc), so may be dying in slow motion. ;-(

Randy


I would not do darkroom without an exhaust.

Are you sure the exhaust is not ducted to the outside? Seems weird to have a bathroom exhaust venting into the ceiling.
More important, is there an inlet for fresh air while the exhaust is on otherwise your exhaust will not pull fumes away.

I used to feel a session in my chest until I installed a decent system.
Also diluting my fixer 1:20 instead of 1:4 seemed to help.
 
I would not do darkroom without an exhaust.

Are you sure the exhaust is not ducted to the outside? Seems weird to have a bathroom exhaust venting into the ceiling.
More important, is there an inlet for fresh air while the exhaust is on otherwise your exhaust will not pull fumes away.

I used to feel a session in my chest until I installed a decent system.
Also diluting my fixer 1:20 instead of 1:4 seemed to help.
Yeah I see severe problems with mold etc. in that scenario.
 
The usual everyday photo chemicals used in film/paper developing are not flammable. There may or may not be alternative processing agents that present a danger but most home developers won't be using them.

As far as venting is concerned you are not venting vapors, just the odor and if your attic is well vented then there should be no problems. But if you want piece of mind why not duct it to the outside..

I've spent most of my life working in the photo business and can tell you unless you or any member of the family has severe allergies the photo chemicals are harmless unless you try drinking them. In fact acidic acid which is used for the stop bath is vinigar once it is mixed with water..

Another fact is that contrary to what environmentalist's claim it is perfectly safe to dump used chemicals into the sewage system. If you are on a septic system as long as you properly treat it it can also go into the septic system..
 
Darkroom chemicals essentially are water, with significant amounts of various salts and acetic acid thrown in - at that point they aren't really different from the chemistry used to make salad, cure bacon or bake bread. Silver may turn you blue if ingested and is harmless otherwise, but only nutcases drink spent fixer. Active developing or colour coupling agents often are potent allergens, but they do not evaporate from the liquid developers - the risk is contact with the liquids themselves, or dust from dried-up spills (and ventilation won't do much to eliminate dust). So no, ventilation may be beneficial in that it reduces humidity (which may damage the building or your darkroom equipment) and provides enough oxygen for you, but it will not do much regarding the (minor) health hazards when operating a darkroom.

Where did that US obsession with "fumes" originate? I've never encountered it anywhere else. Did the US have only one set of workplace safety rules applying both to photographic and printers darkrooms (where coated plates used to be processed in concentrated alcohol and aromatic solvents)?
 
Darkroom chemicals essentially are water, with significant amounts of various salts and acetic acid thrown in - at that point they aren't really different from the chemistry used to make salad, cure bacon or bake bread. Silver may turn you blue if ingested and is harmless otherwise, but only nutcases drink spent fixer. Active developing or colour coupling agents often are potent allergens, but they do not evaporate from the liquid developers - the risk is contact with the liquids themselves, or dust from dried-up spills (and ventilation won't do much to eliminate dust). So no, ventilation may be beneficial in that it reduces humidity (which may damage the building or your darkroom equipment) and provides enough oxygen for you, but it will not do much regarding the (minor) health hazards when operating a darkroom.

Where did that US obsession with "fumes" originate? I've never encountered it anywhere else. Did the US have only one set of workplace safety rules applying both to photographic and printers darkrooms (where coated plates used to be processed in concentrated alcohol and aromatic solvents)?

I have gotten sick from breathing black and white chemical fumes when I worked in a poorly ventilated darkroom. Some people are more sensitive than others, but its not worth the risk when it is pretty inexpensive to set up good ventilation.
 
The basic chemicals used in developing black and white film and paper prints are pretty benign.
Fixer typically has a slight odor, but stop bath and most developers have little to none.

During long printing sessions it can get pretty hot and humid in a small bathroom darkroom.
A lightproof vent installed in the door will increase the effectiveness of your ceiling exhaust fan.
Increased airflow will also help equalize ambient temperature and reduce humidity.

Chris
 
Vents shouldn't just dump into a ceiling space. Do you mean an attic that is vented to the outside ? If this is the case, no worries. I wouldn't worry about it even if it wasn't. Moisture would be more of an issue imo if there's insulation in the space and no exterior venting.
 
Bathroom venting should be directly to the outside, it's a code requirement in most places, because of potential moisture problems.
(whether or not the bathroom is a darkroom).
 
Vents are good (unless they don't vent directly to the outdoors or into a vented space).

Darkroom chemical' odors affect people differently. Unpleasant side effects of odors do not necessarily mean the chemical is damaging your body (an obvious exception would be rare but extreme allergies. It does mean some people will experience temporary discomfort.

Development chemicals for conventional film media have a low toxic threshold. By all means read their MDS. All toxic effects are dose dependent. The issue is different substances have different thresholds. The toxic threshold for cyanides is extremely low. The toxic threshold for distilled water is extremely high (but too much will make you sick or in extreme cases even kill you). Dose dependence means children are at more risk than adults as dosage depends on the ratio of the chemicals' mass to body mass.
 
In my b & w darkroom the two most hazardous chemicals are probably selenium toner (a toxicity hazard) and undiluted glacial acetic acid, used to make indicator stop bath, which is a strong corrosive to skin and inhalation to the lungs. I don't do much selenium toning these days, and now use diluted white vinegar for a stop bath.

In theory, mixing undiluted glacial acetic acid and a solvent such as alcohol could be a fire risk, but that's about the only one I can think of with standard b & w chemistry. Or mixing it with a strong base like drain cleaner.

Of course, any powdered chemistry is an inhalation risk to the lungs if the powder becomes airborne; best to use a paper mask, at least.

Many manufacturer safety data sheets give you hazard assessments for whole body exposure, like having a 55 gallon drum of developer poured on you; these sheets are also written more for use by hazardous responders in the case of a truck or tanker car overturns and spills large quantities. There's much less data for chronic exposure of low levels over a long time. Best to use common sense precautions.

~Joe
 
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