The hazard
A fall from height can kill you or change your life for good, and it happens in a split second. Falls come from unsafe conditions, like an open edge or a loose cover, and from unsafe acts, like unhooking to reach one more spot. Protection only works if it is set up before the work starts and used every time.
The action
Holes in floors and roofs, including skylights, are easy to miss. Covers must be secured so wind, equipment or workers cannot knock them out of place, and they must be color coded or marked HOLE or COVER (29 CFR 1926.502(i)(4)). Never pull a cover unless that hole is protected another way. (29 CFR 1926.502(i)(3))
ASK THE CREW
Can someone show us how to inspect a harness and lanyard, and what would make you take one out of service?
From the talk: Fall protection. Read it in full, free, with the questions and the sign-in sheet.