What's the purpose of accessing the roof? You have to provide everything that's reasonably practicable to ensure safety of employees. If the roof is accessed once a year, installing permanent barriers might be practicable but not reasonable - in this case temporary restriction would suffice. However, marked route on its own might not be enough - it falls in the same category as "sign" to me - it is marked, but whether it helps or not is down to an individual who might decide to step off of it for a second... Remember to eliminate, substitute, use engineering controls, safe system of work and ppe as last resort to control risks - usually in this order (but not always). If there is no way to do the job from the ground, installing permanent barrier might be a good solution but only if employees work there often. If not, maybe access the roof using cherry picker? As I said, I don't know the nature of the job and reason for accessing the roof, so it's difficult to judge. Write something more about it please.

hi guys, thanks for both replies. To give you some more info, the roofs while not used on a daily basis, are used by contractors to access lift plant rooms, certain plant and for gully clearance. So while its not an everyday occurrence my concern is that having none and marking out routes may not be enough. Particularly as individuals may decide to stray from the suggested route and no parapet walls are present. Hope this helps to clarify? any further guidance would be appreciated. Thanks

so essentially we could use man safe as a means of controlling the risk instead of edge protection?

Guys !! All you need to do is to follow the WAH 2005 hierarchy of controls, which is crystal clear and yes it is not an absolute duty but afarp. Basically consider; preventing falls (collective over personal) > fall mitigation (collective over personal) > Training / supervision / instruction etc as being the last.

Flat roof, sorry thought I'd mentioned that, being a doughnut today. :)

It is worth noting that if you are working on roofs (particularly fragile roofs) and thinking of painting lines on the roof or use bunting and the like on the roof to demarcate 'safe' routes or boundaries the HSE's view in their guidance on 'H&S in roof work' is, to quote...." the boundary does not need to comply with full edge protection standards, but there should be a continuous physical barrier (a painted line or bunting is not acceptable)".

Good to see CDM design risk management for end users considered and argued at the very end of the project..... I despair! Simon