Welcome.
I will list the most common things I find, as a OS&H manager:
1. Working live
2. Failed to Lock Out/Tag Out
2. Inadequate PPE
3. Defective tools (i.e. damaged cords, etc)
4. Fall protection (open sided holes/walls)
The list can go on, but that's the most common I find.
Worksafe seems to cover it, but I would add "Test Out" to item 2.
1. Eye protection
2. Ladder safety
3. Hand protection
4. Falls
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