This part of ISO4190 specifies the control devices, buttons and indicators to be provided when a lift (US: elevator) is constructed and installed, taking into account the type of control intended for the lift and also ensuring the ease of access for disabled persons (motor and/or sensory). AnnexB gives particular requirements for access. The description of the controls is given only in order to define the buttons and indicators. It does not constitute a complete description of these controls nor does it attempt to standardize them. This part of ISO4190 also specifies the requirements for handrails when provided in the car. It is applicable to lifts of classes I to IV and VI as defined in ISO4190-1 and ISO4190-2. Group collective lifts have common controls and are electrically interconnected so as to provide a better service and for reasons of economy. The system can be more or less complex according to the number of lifts and the expected traffic. Consequently, this part of ISO4190 does not deal with supplementary signals which the manufacturer may consider useful (e.g. “next car??, “stand clear of the doors??). The following are not dealt with in this part of ISO4190: special features (and their corresponding signals), such as certain features for improving the service of bed lifts, touch screens or voice activators; any devices for speeding the traffic in the case of automatic doors (variable time delays according to different criteria, closing button, light ray, etc.). The requirements of this part of ISO4190 are intended to be followed in all cases where the controls and the basic signals are concerned, and can also be used as a guide in developing supplementary signals.