Do you need to have any fall protection if you work on a roof?

All of our sites have fall protection to protect roofing contractors and all other trades from falling off the roof. 

See photos for the fall protection now used and should be used on all sites to protect workers from falls. When I did my building apprenticeship in the 70's, we had no fall protection and many building contractors had falls from roofs. 

Lucky that nowadays we have better safety standards and practices then yesteryear and a lot less injury because of it.