Cite, please? How does that happen, exactly, unless the sodium chloride is washed out of the formation, leaving non-sodium chloride deposits behind? In which case, the salt isn’t “losing its savour,” it’s simply being washed away.
Sometimes, one of my kids will pick up a bottle of water from the counter and ask, “Is this water old?” To which I invariably reply, “Yeah, about 4 and a half billion years old.”
Without getting too involved in the deficiencies of that lab;
The fact is no one was taking the time to look up the MSDSs (which often were only available in English, and all typed differently to make it annoying to find the same info on each version from different suppliers). People get remarkably lazy and complacent when they work with chemicals for a long time. Seeing out PPE, or ordering more when we ran out of something, seemed to be beyond most people’s abilities :rolleyes:
H&S decided that they wanted a simple, quick reference list of Drug/Reagent, Category, Effects of Exposure/Known toxicity, and Appropriate PPE. So until the person making the table got to that item on the list the new list/table they were making had a default worst-case-scenario of 4. It was a place holder, but it was still pretty damn funny.
Also; consider the fact that for a 700+ employee company, the H&S department really only consisted of 2 people. Many (most) H&S issues were left to the individual departments within the company, making the whole thing inefficient and, frankly, unsafe. I had major issues with their approach to pretty much everything, but the 2 people never had time/resources to ever actually DO anything to resolve any issues. I don’t work there anymore, and I don’t intend to ever go back (though that’s mostly for other reasons).
That may be tricky as it seems to be something which varies by state:
Source: US Dept of Agriculture
WAG: Maybe to allow foods to easily be sold nationwide some manufacturers just go with whichever state has the most stringent requirements?
And, as noted, maybe salt isn’t dated in response to a law or regulation, but rather in order to appear as if it is “fresh.”
Not to completely hijack the thread, I’ve worked in lots of labs, and I invariably end up taking over the MSDSs, because no one ever manages them well.
BUT, at almost every place I’ve worked, someone does highlight the revision date, the Emergency response section, and the NPFA ratings (or some equivalent). [Then, of course, they file them in some inconvenient place and no one ever looks at them again.]
I love HPLC Water MSDSs; they invariably tell one to treat eye exposure by flushing the eye with water for 15 minutes.
This sounds worse than the programmer stuck in the shower. 
Yeah, that’s what should happen. But the MSDSs came in, would be scanned onto the network, and the originals placed in a binder (in order of arrival). The binder wasn’t in the lab - we’d have to get a computer (which were shared to begin with) and look them up one by one in a folder, a serious PITA).
Seriously, that place was messed up when it came to health and safety - a fact that grated on my nerves every single day I worked there. Despite having mercury thermometers, there was no mercury spill kit. There was only one type of glove, though certain solvents are better with nitrile than latex (etc). People were weighing benzene derivatives on open, uncovered balances, without any sort of respiratory protection whatsoever. A mess. I did what I could, and worked there for a year, but since it wasn’t my job (I was a chemist), I was limited in time and resources. I did manage to create and write SOPs for emergency spill response, train designated people as a response team, organize respiratory protection to be provided to all chemists (particle and solvent masks), conduct lab audits every 2 months or so (H&S and GMP)…
hehehe I sound defensive, don’t I? I don’t mean to be. H&S is something I actually take very seriously, and this place was an interesting challenge and a horrible frustration all in one! If my new career choice doesn’t work out, it is likely to be a back-up choice I’d make.
Ok, enough with the hijack! 
Audiophiles say it’s a good idea to trim the ends of your copper speaker cable wires every six months (in a humid or seaside climate) or year (everywhere else), because oxidation and dust on the exposed copper detracts from the ultimate sound. Audiophiles have been known to propound a number of silly things, but this tip is almost singularly sensible (and cheap).
My Googling isn’t working too well, but
from http://www.food.gov.uk/foodindustry/guidancenotes/labelregsguidance/usebydateguid
However I can’t find the text of the EC directive so I’m not sure what that “most” excludes.
Incidentally, in the UK at least, there is a distinction between “Use By” dates, which are used on perishable goods which may be dangerous to consume after that date, and “Best Before” dates which are more advisory and indicate that the food may be past its best after this date.
So I would expect a Best Before date rather than a Use By date on salt, if any. However I just checked my pack of salt and there is no date on it. (It does say, “Saxa Rock Salt is over 200 million years old, formed through ancient geological processes in the rocks of German mountain ranges”, so I guess they thought it would be silly.)
So I take back my earlier answer that it is required by law.
The exposed copper has nothing to do with it. It’s exposed, after all. If there’s some crud at the interface point, then maybe they have something to go on there, but if it’s an adequately tight connection, then the contact points are isolated from the atmosphere and won’t corrode or get dusty.
mnemosyne, you are not alone. I have been there, and, like you, found that the only way to get things done was to do it myself.
About that salt: it is hygroscopic, so that’s one reason for it to have a Use By Date.
Oh, wait, the OP had rock salt.
And don’t assume those dates have necessarily even been researched. I used to work for a company that set its expiration dates by trotting across the street to the Wal-Mart and seeing what their competitors put on their products.
My box of Kosher salt appears to have reached it’s use by date, since it has coalesced back into solid form. I tried to refill my salt dish the other day and it just went “thunk” as the chunk slid to the other side.
If the OP has the same brand of sea salt in a grinder bottle I have, the grinder is plastic. 
I have a McCormick’s Sea Salt Grinder. I’m not sure if the grinder is self cleaning/non-clogging in design on not, but they also put in some kind of other powdery substance to help with moisture I think. Yeah, an anti-caking agent, Yellow Prussiate of Soda.
I thought they were kidding.
Apparently they weren’t kidding [Warning: PDF].
It also contains this gem:
Oh no I spilled some distilled water! Better pour some more water on it before soaking it up with some paper towels, you know, to be on the safe side. :smack: