So day in day out all day - protect from falls and other hazards. Once in a while - couple times a day - no big deal. Hmm. Let's see, 2- broken knee caps, ladder inverted, 2-broken wrists, roofing fall, broken 4th neck vetibra, roofing fall, 2-broken ankles, ladder slid out, concussion/ coma for two wks ladder, fell back and away. These are guys I've known. Not up day to day, not roofers, but service people cleaning, inspecting, doing installs where 90% of the work is elsewhere. Just saying. It can be a hassle to prevent a mishap, so be careful. I built scaffolding for a recent build, 12/12 pitch. Researching wood scaffolds, osha style, was a study in requirements - what does it take to prevent injury. So I built the required scaffolding, and was very impressed. Not just once, but a dozen times, 45min to assemble, 25min to tear down, move, rebuild, repeat. But wouldn't you know, one time I omitted something, and in time that reqirement became clear. Not in an alarming way, but- maybe a little wind, maybe some frost, maybe. Easy to do, easy to f-up.