D-marc™105 is classed as a form of Collective Fall Protection in accordance with the HSE’s hierarchy of risk management as set out within the Working at Height Regulations 2005 (WAHR). The WAHR 2005 Part 3 illustrate the use of demarcation barriers as an “example of taking other additional suitable and sufficient measures to prevent a fall”. The demarcation barrier system is to be placed a safe distance from the fall hazard (normally 2 m).
Health and Safety in Roofwork HSG33 states that 'where work is not done at the edge, demarcation barriers can be provided at a safe distance from the edge. (usually at least 2 meters). Eg work on an air conditioning unit in the middle of a roof.'