Some positions need a certificate: first aid, food safety, a provincial serving licence, a driver's abstract. If yours does, the organization records it against your account.
Getting one on your record
Usually you give the organization a copy and somebody enters it. Some organizations let you upload it yourself from your account; if you do not see the option, yours does not.
What is recorded is the kind of certificate, the number if it has one, when it was issued and when it expires. The file itself, if you uploaded one, is visible only to the few people who are allowed to see that sort of thing.
Expiry
A certificate with an expiry date is watched. As the date approaches your record moves to *expiring* and the organization can see it coming; after the date it is no longer counted, and positions that require it stop being open to you.
You will normally be told before that happens, which is the whole reason the date is recorded. Renew it, send the new one in, and the record is updated — the old one stays on your history rather than being overwritten.
Why a shift is closed to you
If a position lists a requirement you do not hold, or hold an expired version of, you will not be offered it. The reason is shown rather than hidden, so you know whether it is worth renewing a ticket to get the shift you wanted.
If you are sure you hold something the system says you do not, tell your coordinator. It is almost always a certificate that was never entered.