3020 – 09 – Types of Safeguarding Devices 2

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By interrupting a machine’s normal cycle, safeguarding devices protect workers, keeping the operators hands well away from the point of operation and moving machine components. Safeguards are separated into a range of different categories.
• Wrist devices attach to the operator’s wrists and connect them to the machine. While these devices have largely gone out of use, older machines may still have them. Wrist devices are divided into two different categories:
– Restraining devices prevent worker’s hands from accessing hazardous parts of the machine.
– Pullback devices remove the worker’s hands when the machine starts.
• Sensing devices are placed into the control system to regulate the machine’s action. Presence-sensing devices, for example, are often placed in mats around the machine. They enable the machine to stop as soon as it detects a safety hazard.
• Trip controls deactivate the machine when triggered. Trip controls are often rods or wires that are modified to be pressure-sensitive.
• Two-handed devices, as their name suggests, require both hands to be used. A two-handed trip device, for example, means that the machine requires operators to use both hands to activate the machine. Once the machine starts, though, workers have their hands to themselves. These devices need to be placed as far away as possible from the point of operation.
• Gates are barriers that can be moved. They’re typically used during metal cutting actions. There are two kinds of gate barriers:
• Type A gates won’t let you get to hazardous areas during production.
• Type B gates shield the operator when the tool touches the workpiece, but those shields lift after the cut is finished.