Abseiling, a mountaineering technique also known as rappelling, is being used by many inspection firms and public works departments in Britain for building and bridge inspection, replacing conventional access by scaffolding and platforms. According to John Barry, managing director of Ab-Train, abseiling is quicker, cheaper, easier, and safer than scaffolding or other forms of access. The equipment is simple and easy to maintain, and inspectors have both hands free to make on-the-spot tests and repairs. Ab-Train reports it can train inspection teams in just 6 or 7 days using introductory mountaineering instructional methods.
To set up for an abseil, two anchors are attached to existing strong points on the top of the building, such as a lift housing or water tower. A rope is attached to each anchor and run from the top of the structure to the ground. The abseiler is suspended from the ropes by a harness system. Gravity supplies the power for descent and a frictional device or rack attached to both ropes is used for a smooth, controlled descent. Because abseiling uses two independent ropes, each hooked to a separate anchor and each with a breaking load five times the safe working load, inspectors can be confident of their safety. Also, time and costs savings are significant.