Lockout-tagout equipment safety lock - GIF and photo

[Frank S]

those scissor style hasps have been banned at a number of sites I've worked because they are prone to failure. The newer captive style hasps are being used since they are harder to fail without deliberate tampering.
The scissor style can be inadvertently twisted whilst people are fitting locks, causing the jaws to bend open, and eventually slip off the locking point.

In a world where only professional persons work around things that require a safety lockout a simple red zip tie or series of them should be sufficient. But few of us ever get to work in a perfect world atmosphere