§190 制御装置の不意の操作の防止

The requirement set out in the sixth indent of section 1.2.2 aims to avoid inadvertent operation of control devices. Inadvertent operation can result from various causes, such as, for example, accidental contact between a part of the operator's body or of his or her clothing and a control device, unintentional operation of two adjacent control devices (for example, pushing two buttons or levers with one hand or two pedals with one foot), a control device being caught on an obstacle in the environment of the machinery or use of a control device as a hand hold for access to the operating position – see §317: comments on section 3.4.5.

Such risks must be assessed for the different phases of the foreseeable lifetime of the machinery, taking account of the operators' tasks and the corresponding operation modes, and must be prevented by appropriate design measures. Such measures include, for example:

designing the control devices with sufficient resistance to avoid inadvertent operation by slight pressure;

positioning the control devices in a recess or surrounding them with a collar;

positioning and/or guarding control devices, to prevent contact with parts of the operator's body or clothing and to prevent them from being caught on obstacles in the environment of the machinery;

fitting control devices, the operation of which requires two independent actions;

fitting control devices with a lock.

Where there is a risk arising from an operator falling onto or being pressed against the controls, then means to prevent dangerous movement of the machine should be taken. A number of fatal accidents have occurred with a variety of machinery such as MEWPs; loader cranes; and interchangeable digging equipment. If such a risk cannot be eliminated by the controls’ location and mode of operation, then other means must be taken such as designing the controls with a trip feature when excessive pressure is used or fitting other trip devices.