In accordance with the Machinery Directive 2006/42/EC, any reasonably foreseeable misuse of the equipment must be taken into account when designing the machine.

Unintended misuse or incorrect use refers to human error and accidental errors. Intentional misuse or incorrect use refers to deliberate violations committed by a person.

Designers of machinery and mechanisms consider and analyse unintentional misuse and examine accident reports in which unintentional misuse has led to an industrial accident.

Unintentional human errors not associated with deliberate actions, as opposed to deliberate errors, are classified as mistakes.

Mistakes are divided into three categories:

·        The first category comprises knowledge-based errors, where the mistake results from a lack of knowledge or training.

·        The second category comprises errors and oversights arising from incomplete instructions, which occur when there are deficiencies or weaknesses in the system or rules relating to the process.

·        The third category relates to errors and misjudgements associated with temporary, short-term lapses, for example, whilst performing work tasks. As a result, the machinery may unintentionally start up or perform some other hazardous function. In such a situation, the level of risk depends on how well the controls are protected, how they are positioned, and how the moving parts of the machine are protected.

The human factor is taken into account in the safety requirements of the new Machinery Directive, in particular in the provisions concerning control systems.

Common errors and misjudgements made by people that must be taken into account when designing a control system include, for example, failure to perform a necessary function, or performing a function too late or too early.

Other possible errors may involve performing additional, unnecessary or incorrect functions.