How seriously should I take expiration dates on chemicals?

[Leonard Evens]

I have some D76 in a sealed foil package which is marked with an expiration date in 2010. How seriously should I take that?

Similarly, I have fixer in sealed foil packages with expiration dates going back to 2008 or earlier. Same question?

Finally I have two plastic bottles of Kodafix solution without dates on them that I could find, but they are pretty old.
One, which had been opened and which I had been using has some powder precipitate on the bottom, and I think I should dispose of that. But the other has never been opened and looks completely clear. Same question?

[WayneStevenson]

Not seriously at all. Mix and see for yourself. It will be just fine.

[polyglot]

Ditch the liquid fixer if it smells strongly sulfurous, but it's probably OK for use on film (not paper) for a little while. The powders should be fine as long as the envelopes are completely undamaged, i.e. no pinholes etc.

[Doremus Scudder]

Leonard,

The developers will likely be usable if the packaging is not damaged and still air tight. Mix them. If the stock solution is clear or just a bit brownish, you are good to go. If it mixes dark brown (coffee color), it is oxidized to the point where its activity will be affected.

As for the fixer: liquid fixer concentrates have a roughly two-year shelf life, depending on storage. As mentioned above, the problem is sulfur precipitation, which renders the fixer inactive. If you have visible precipitates or the fixer smells like hydrogen sulfide, then it is likely not good. To test, you can mix a working solution and do a clip test. Compare that to the same test in known fresh fixer. If it is the same, you can use the fixer without worry.

Best,

Doremus

[Michael E]

"How seriously should I take expiration dates on chemicals?"

Not seriously if you can test it - developer for prints, for example. Very seriously if you risk losing important work - developer for film, for example. That being said,
I still use powder chemicals from east german ORWO production, expired in the late 1980s. Except for some dark brown film developer from sealed packages, I have not noticed any deterioration. I have stacks of chemicals to last for decades, so it makes sense to test and run them. If I had only a package or two, I would rather dump it and work with fresh chemicals and peace of mind.

Michael

[Joseph O'Neil]

Depends on the chemical. As others have pointed out, D-76 or other Kodak dry chemicals in a sealed bag will likely survive the next apocalypse. In liquid, I have several bottles of HC-110, and in their undiluted form, sealed and unopened, they seem t last forever.

Liquid fixer however seems to go bad faster however, so judge accordingly

joe

[SpeedGraphicMan]

Test and see.

It not like you are eating it

[Tom Monego]

I have some D76 in a sealed foil package which is marked with an expiration date in 2010. How seriously should I take that?

Similarly, I have fixer in sealed foil packages with expiration dates going back to 2008 or earlier. Same question?

Finally I have two plastic bottles of Kodafix solution without dates on them that I could find, but they are pretty old.
One, which had been opened and which I had been using has some powder precipitate on the bottom, and I think I should dispose of that. But the other has never been opened and looks completely clear. Same question?

Powdered chemicals in a sealed bag will generally be fine, as said before if dark brown when mixed it is NG. If the powder has brown flecks in it that is likely oxidized developing agent and it will be NG.
Liquid fixer precipitates and gets smelly when acid hardener has been added, if the fixer has no precipitates and only a slightly obnoxious smell it should be fine.

Tom