What course is it that you need for this and relevant qualification ?
TIA Matt.
Just the ability to do a Health and Saftey risk assesment. There is no course per se for working on flat roofs. The assesment will decide if saftey guides need to be fitted so you can attatch a fall arrest harness to, and a safe means of access and egress to the flat roof will also be required to be noted. Other than that, you're good to go. Assuming the assesment also identified the roof as sound to walk on as regards to weight bearing.
Of course the work duration and frequency might dictate and complete saftey rail is fitted around the perimiter of the flat roof too, as opposed to using a fall arrest harness.
Or do as i do, get a big fat mate (imagine Eddie Yates) to run up a ladder, stand on the roof and shout.."yeah, its sound lah, you can all get up " !!!!