The technical rules for workplaces, ASR A2.1 "protection against falls and falling objects, entering hazardous areas" specify the requirements regarding how to set up and use workplaces and access routes so as to provide adequate protection against falls and falling objects, as well as the requirements regarding associated measures for crossing a roof surface and/or any other hazardous area. These ASR A2.1 rules, therefore, represent fundamental requirements pertaining to setting up a fall arrest system.
According to ASR A2.1, "[...] there is a danger of falling [...] as soon as the distance to the ground below exceeds 1.0 m." Analogous to the provisions of the German employers' liability insurance associations, ASR A2.1 also ranks the measures by stating that collective protection should always take precedence over the use of individual PPE. Guard rails are preferable to anchorage devices, in as far as the structural, resp. operational situation allows for this.