Foreseeable misuse of equipment.

During the stage of defining safety requirements for machinery and its control systems, decisions are made that affect safety at all subsequent stages of the machinery’s life cycle. Errors made when defining safety requirements during the design phase are the cause of a significant proportion of accidents.

A mandatory risk assessment forms part of the design and manufacture of machinery; this identifies the hazards posed by the machinery and, where necessary, reduces the associated risks. In addition to the intended use of the machinery, the risk assessment must take into account reasonably foreseeable misuse.

In many cases, deliberate, foreseeable misuse involves the permanent or temporary bypassing of safety devices, or failure to comply with safety rules and instructions. Unintentional, foreseeable misuse often involves errors or oversights caused by human carelessness or haste.

According to the definition in the Machinery Directive (2006/42/EC), reasonably foreseeable misuse refers to the use of machinery in a manner not described in the operating instructions, but which constitutes easily predictable human behaviour.

According to standard EN ISO 12100:2010, unintentional user behaviour or reasonably foreseeable misuse refers, for example, to a loss of control over the machinery or reflexive human behaviour during a malfunction or failure of the machinery. Other examples of foreseeable misuse include loss of concentration or carelessness, as well as human behaviour driven by the urgent need to keep the machine running regardless of the situation.

Foreseeable misuse of equipment can be divided into unintentional and intentional.

Unintentional misuse of equipment includes, amongst other things, a cognitive error where a person misunderstands the instructions received. Failure to perform a required action as a result of an error, and accidentally pressing a control due to a slip, are considered reasonably foreseeable misuse.