A roof access strategy was developed following the hierachy of safety—striving to acheive a collective protection solution to the whole of the roof area. To develop the access stategy two key points need to be established. Firstly, the points of access to the roof are noted. Secondly, the areas of the roof requiring regular maintenance access need to be identified—on this project they are air conditioning plant and associated air handling units. From this information the roof access strategy was then created. D-marc was used extensively as part of the collective protection system to create clearly defined safe access routes across the roof to the places requiring regular maintenance work. D-marc was then used to demarcate the safe working zones upon the roof top. In isolated areas where it was not possible to keep the worker away from the fall hazard a guardrail was used. The easy to install, non penetrating D-marc system creates a clearly defined access route and a safe working zone for all those undertaking maintenance work on the Crown Woods college roofs.