4. 防护设备

4.1 防护设备选择

标准EN ISO 12100 2中针对防护设备选择的注释

若不能通过建设性的措施防范或有效限制危害的发生,这时就必须规划和使用防护设备。应根据当前针对该机械的具体规定,如欧洲C标准,或根据对具体机械的风险评价来选择合适的防护设备。

通常防护设备应能够保证操作简便和符合人体工程学、同时又不干扰正常使用,否则会导致为了方便操作机械而绕开防护设备的危险。

在正常操作过程中,若操作人员不需要进入危险区域,此时就需要安装固定护罩(如栅栏)。如果操作中需要经常进入危险区域,则应使用电子感应式防护设备(如安全光幕)或可移动护罩(如带安全开关的门)。

Selecting protective devices: Application advantages – application limits

Type of protective deviceApplication advantagesApplication limits
Fixed hard guard (e.g. fence, cover)Long lifetime, protection against injury caused by projected (thrown out) parts, objects.Cannot be used if frequent access to the danger zone is required. More difficult access with maintenance work. Can be removed without being noticed. Safety distance required (EN ISO 13857).

Moveable guard without guard interlocking (e.g. doors with flaps) with Safety Switches (without guard interlocking).Access to machine is possible. Doors cannot be removed without being noticed.Protective door can be opened during the operation. Cannot be used if the machine’s stopping time is greater than the person’s access time. Hampers operation when frequent access to the danger zone is required. Safety distance required (EN ISO 13857).
Moveable guard with guard interlocking (e.g. door or flap with safety guard interlocking).The protective door can only be opened with an electric unlocking signal. Prevention of unexpected production interruptions. No safety distance required.Limited use if frequent access to the danger zone is required.
Light Beam Safety Devices, Multiple Light Beam Safety Devices, Safety Light Curtains Access and ergonomic operation of the machine possible. Unobstructed material transport through the protective field is possible with combination with a muting function.Safety distance required EN ISO 13855. No protection against injury caused by projected (thrown out) parts, objects.
Safety Laser ScannersAccess and ergonomic operation of the machine possible. Flexible adjustment of the protective field according to the respective danger zone.Limited use in environments with heavy dirt build-up. Safety distance required EN ISO 13855. No protection against injury caused by projected (thrown out) parts, objects.
Two-hand controlsLocation-dependent protective device with control function. Both of the operator's hands are required for machine activation and therefore protected against injuries.Only protects the person operating the two-hand control device. Other people nearby are not protected. Safety distance required, EN ISO 13855.
E‑StopsPress button(s) for stopping the machine to prevent immediate or threatening hazardous situations.Additional cautionary measures for emergencies. Not a replacement for other protective measures. The press buttons must be placed within range of the points of operation.

General requirements for construction of protective devices

EN ISO 12100‑2 "Safety of machinery - Basic concepts, general principles for design - Part 2: Technical principles" contains the following general constructive requirements:

Guards and electrosensitive protective devices

  • Must take mechanical and other hazards into account.
  • Must be built hard-wearing and robust.
  • Must not cause any additional hazards.
  • Must not be easily bypassed or made ineffective.
  • Must be a sufficient distance away from the danger zone (see EN ISO 13857).
  • Must not obstruct the machine operation and the work process more than necessary in order to reduce every incentive to go around it.
  • Must permit interventions to use or change tools or for maintenance work as much as possible without removing the protective devices. The access here must remain restricted to the area required for the work.