26 n INDUSTRIAL SAFETY May 2025 www.drivesncontrols.com Enhancing safety in manufacturing environments As manufacturing continues to become increasingly automated, manufacturers are looking for ways to protect their most important asset: their workforce. Robots, autonomous vehicles, material-handling equipment and other systems, can create more dangerous workspaces than ever before if the proper safeguards are not installed on the production oor. There are many forms of safety devices available today. Below are a few to get you thinking about the options available. E-Stops (emergency stops) These are one of the most recognisable safety devices on the production oor. Think of them as the immediate interface to stop a machine. The e-Stop is typically normally in a closed position in a circuit. When pressed, it opens the circuit and cuts power to the device. To re-engage the circuit, the e-Stop must be pulled out or in a twist to open conguration returning the circuit to operational status. According to OSHA, ANSI, NFPA79 and ISO 13850, IEC 60204-1, e-Stops have to be installed where they are easily accessible to the operator and resetting the e-Stop should not allow operations to resume. A second redundant action is required – such as an allclear function via a PLC circuit. Door interlocks These are another physical safety device commonly integrated on the production oor. Safety interlocks are used on physical barriers such as gates and doors. In a similar way to an e-Stop, the safety interlock operates in a normally closed circuit. When the gate or door is opened, the circuit is interrupted, and work is halted. Interlocks are required to meet ISO 14119 and ISO 13849. Operator presence triggers These come in many shapes and sizes. For example, a safety mat can be activated by the presence of someone standing on it. It may trigger a machine to stop, go into reverse, or deactivate when presence is detected. This helps to ensure that human workers are out of the way, allowing the machine to operate safely. Laser safety scanners These have become very popular with the rise of cobots. The scanner uses a 360-degree beam that indicates how close a worker or an object is in relation to the robot. The robot will decrease speed depending on the closeness of the individual or object, using zones. In an orange or yellow zone, the robot slows to a collaborative speed until the object or person exits. If the red zone is triggered, the robot will slow or stop completely until safe. Light curtains These are especially eective in areas where crushing or pinching hazards exist – such as hydraulic presses. The light curtain uses photoelectric beams that project from a transmitter to a receiver. If the beam is broken, all work stops immediately until the obstruction is cleared. Light curtains are particularly eective when solid gates or barricades are impractical. They come in a variety of sizes and levels of sensitivity to help manufacturers to meet safety standards. Safety PLCs These are designed to monitor and manage safety-critical functions and serve as a way to program safeguards to monitor the health of a line. Through redundancies, the safety PLC is designed to run diagnostics to determine if a part of a line or a component is faulty. In an event such as a broken wire or a motor running outside of spec, the safety PLC will immediately shut down the entire aected system to help prevent injury or damage. The safety PLC must adhere to a specic safety integrity level (SIL) and must meet IEC 62061, ISO 13849-1 and IEC 61058. These are just some of the many safety devices available to manufacturers and installers today. When automating a process, it is necessary to seek advice from a safety expert or consultant to ensure you have covered all the possible hazards within your facility to protect your workforce and investment. These experts can help you to navigate the safety regulations. n There are a variety of technologies designed to help ensure safety on factory oors. Eric J Halvorson, senior marketing technology manager for automation and control at DigiKey, explains some of the key options.
RkJQdWJsaXNoZXIy MjQ0NzM=