Good morning,
There are a lot of ways that you can handle it. The way that I will be handling a similar use case is by using the URL to that Tool and having buttons to allow the people to Check it out for calibration or check it back into service. The issue with using a QR Code is it is very susceptible to damage, and will become useless if it is damaged. So, I would recommend using a Barcode instead, and Javascript code set on a homepage that will allow people to check out and check in the tools.
Good luck!
John
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John Crosland
Software Developer
Inglett & Stubbs
Mableton GA
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