Argon (CAS 7440-37-1): storage and disposal

On a university site it generally stands next to the glove box or instrument it feeds, chained to a wall bracket, and often with a second spare nearby. Spare cylinders are where standards slip. Each one needs to be upright and secured, with its valve guard on, and clear of ovens, radiators and direct sun. Research groups often leave cylinders behind when they move, and a corner of a shared store can collect several with no clear owner. Give each a tag showing the group responsible and the date it arrived, so the rental can be tracked and the cylinder can go back. Do not puncture or vent one to tidy up, and never strip a regulator from a cylinder you are unsure about.

Age does nothing to argon. It is a noble gas that does not react or break down, so a cylinder from years ago may hold exactly what it did on delivery. The changes worth looking for are on the steel and the fittings. Rust at the foot, dents, a bent valve and a missing guard are the common ones. A worn supplier label may also leave it impossible to tell what is inside, and shoulder colour alone should not be used to decide. A test mark that looks very old is a reason to raise it with the owner. Any hiss around the valve suggests a leak, and because argon is heavier than air and displaces oxygen, leave the room, keep others out and report it. With a gas that shows nothing itself, the record and the label do the most useful work.

This does not go through our standard collection route. It is arranged by manual enquiry, and never goes down the drain or into general waste.

A supplier's vehicle is how it normally leaves, as cylinders generally remain the property of the gas company and go back to them. Inherited stock from a departed research group is the difficult case, since a label may name a supplier the site no longer uses. Contact them anyway. This site does not quote for pressure containers online, and they do not go in a lab pack, so where no owner can be traced, send a manual enquiry with a photograph, the label wording, the size and the location. A store assessment is recommended if there are several. Keep each one upright and secured until you have advice. Do not vent or puncture any cylinder, and do not put one in a general waste bin or skip.

Usually held as: cylinder.

Tell us the container size and how many you hold. An estimate is enough to start with, and some items cannot be priced until someone has looked at them.