can i use B&W chemicals in the bathtub?

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I am setting up a temporary B&W darkroom in a bathroom. Can I put the print washer in the clawfoot bathtub or will it damage it? Is it hazardous to take a bath in the tub after it's cleaned? I will most likely use some kind of plastic lining but I will inevitably have some spills.

-- Molly Ann (mollyaf@pacbell.net), December 06, 2001

Answers

There should be no hazard to you in using a bath after any normal photographic chemicals have been in contact with it, if it's been flushed out with water afterwards.
The major hazard to your person from photographic chemistry is a risk of dermatitis from contact with developer. This is more of an allergy reaction; some lucky people (like myself) can dabble their bare hands in developer for years with no problem, while others get a skin rash with just a splash. Surgical gloves are the best option. They're cheap, disposible, and allow you to handle prints with dexterity, while giving your hands total protection from processing chemicals. I only wear one glove, on my right hand. This gives me a dry left hand for handling unprocessed paper.
Stop bath and fixer can both have a pungent smell, and they should be used in a reasonably well-ventilated area. The long term health risk of exposure to the vapours doesn't seem to be that well documented, but probably doesn't give any great cause for alarm, in any case. Working strength stop-bath presents about the same hazard as household vinegar, and the smell from fixer is due to it being a weak solution of sulphurous acid. These fumes may bring on an asthma attack if you suffer from asthma, and that's probably the greatest risk.

The hazard to your bathtub will be twofold:
1) Staining of the enamel. If you let developer or used fixer lie on the enamel for any length of time, then it'll stain the finish, and the stains won't be easy to remove.
2) Etching or staining of the chromework of the bath. If you have a chromed drainhole in your bath, it can be attacked by fixer or stop bath. Fresh fixer will tend to etch the chrome finish, and used fixer will plate grey deposits of silver on it. You shouldn't pour fixer down the drain for environmental reasons anyway, but the small amount of fixer at very weak dilutions that gets washed out during film or print washing is OK. It won't harm your chromework, and should be well within allowable contamination limits for waste water discharge, unless you have very draconian local bye-laws.

To sum up: The standard photographic chemicals (developer, stop bath and fixer) don't present too much of a personal hazard by brief external skin contact. They are toxic, though, and you obviously don't want to drink any of them!
Take sensible precautions with photographic chemicals, as you would for household bleach, detergent, or other cleaning products, and KEEP THEM WELL LABELLED AND OUT OF REACH OF CHILDREN.

-- Pete Andrews (p.l.andrews@bham.ac.uk), December 07, 2001.


Pete gave you an excellent answer. I would only add, that the weight of the washer when filled with water makes abrasion damage possible. Try a bath mat or a diswasher mat to avoid sratching the tub.

-- Charlie Strack (charlie_strack@sti.com), December 07, 2001.

Molly:

One thing to be careful about. If this clawfoot tub is old, there is a possibility that the hardened surface of the enamel has been worn away, especially with heavy use of abrasive cleaners. If that is the case, the underlying porous layer will tend to absorb chemicals into the pores, thereby leaving unremoveable stains. If the enamel is still in good shape, then that problem won't be an issue.

-- Ken Burns (kenburns@twave.net), December 07, 2001.


To interject a little about stain removal. You can get some muriatic acid from the hardware store and be cautious that you have plenty of ventilation when you use it. It can be used to remove stains that otherwise be impossible from ceramics with no damage to the surface. I've removed old rust stains (and unidentifyable ones) from old tubs that came out flawless. But do use rubber gloves and plenty of ventilation because the vapors are harmful. But this is a last resort solution, not for the novice!!!

-- Jim Darcy (jimdarcy55@yahoo.com), December 11, 2001.

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