The general consensus amongst those funded by the taxpayer, perhaps?
Those who dwell in the Real World have to minimise expenses by, for example, applying a bit of what we might call nous.
For example:- although we know that it's working just fine, and even suspect that it's well within spec, test equipment item No.1 gets sent away to gain its (expensive) seal of approval.
When at long last we see it again (after being bounced - and, most likely, chucked and kicked - about in various vans), we assume that it's now "perfect", especially as it now carries that all-important feature ... a piece of paper.
But (cunning folk that we are), we now compare (and, if necessary - but it seemingly never is - re-calibrate ... as in "adjust") test equipment No.2 ... No.100 against No.1. Traceable to "national standards"? Yes, why not (just as long as it's documented ... as in "noted, signed and dated in the test equipment log book")?
You are fishing for gems? OK, here's the first one:- you just need to be thoughtful about which bits of test kit you select for "sending away". Send the one(s) with "all the features". Whilst also bearing in mind that some things matter more than others. For instance, what sort of tolerance is good enough on a multi-meter? Or, for that matter an electrical safety tester?
And here's another:- check all your test kit yourself, then only send away the ones that fail that most stringent of the Laws of Physics. You know, the one attributed (quite rightly) to Herr Georg Ohm.
Joe has already mentioned "Indication - for Reference Only", but I would extend this even further by suggesting that such instruments (if you know them, and feel confident about using them) are entirely adequate for the vast amount of testing (checking, fault finding) work carried out in the workshop.
So there's the final "gem":- get some suitable stickers made!
Unless, of course, you work for the NHS ... when you might as well send away the whole lot, and then let them sit prettily on the shelf for yet another year!