The position of the user’s attachment point to the personal fall protection system in relation to the anchor point is of particular importance. This determines the “fall factor”, which provides an indication of the length and severity of a potential fall.
The fall factor is calculated by taking the free fall distance and dividing it by the length of lanyard available to arrest it (in this case the length of the energy-absorbing lanyard prior to deployment of the energy absorber). In a normal work situation, the maximum fall factor is 2.
The fall factor should always be kept as small as possible, i.e. the length of any potential fall should be minimized, for example by choosing an anchor point above the user, and the length of the lanyard should be kept as short as possible.
As illustrated below, an anchor point above the user gives the smallest fall factor, so is the safest, and is the preferred option; an anchor point at shoulder level gives a larger fall factor and should only be used as a second choice; an anchor point at foot level gives the maximum fall factor and whilst acceptable should always be the last option.