It’s doubtful whether primates gave much thought to how reliable their first makeshift climbing aids were as they leapt up them to a place of safety away from hungry beasts. If a support gave way, it would be too late to repair it. However, our priorities today when building stairways are also different to those of medieval builders, who favored spiral staircases that twisted clockwise on the way up. This design automatically gave defenders an advantage, as they had more space to swing their swords down on attackers fighting their way up from below. Although stairways may serve different purposes today, there is one thing about them that has not changed – stairways and platforms are still helpful structures that are used every day, all around the world and with great success. What’s more, users don’t need to worry about their safety as they use them.
Numerous falls and accidents on stairways have been analyzed and one thing is very clear – the main causes of such incidents are poor design and defects caused through use. In Germany, the organizations responsible for statutory accident insurance have collected clear data – in 1980 there were 60,000 reportable accidents on stairways every year. Some 80 percent of stairway accidents occurred when the victims were descending the stairs and were usually caused by slipping on the edge of a step. Around a third of all accidents occurred on steps with a going of less than 26 centimeters. By the year 2000 – some twenty years later and following the introduction of building regulations – there were 44,000 accidents per year, down by almost a third.
There are countless regulations designed to deliver improved safety for users. The most important can be found in international standard ISO 14122, Safety of machinery – Permanent means of access to machinery. This standard sets out the general requirements for permanent and movable means of access to machinery that cannot otherwise be accessed directly from ground level or from the same level. The guidelines here are based on this standard, which applies to working platforms, walkways, stairways, stepladders, and guard-rails that are: