Integrated Safety Devices Prevent Workplace Hazards
Machine hazards are a reality for workers in industrial settings. The most challenging areas include those where potentially hazardous operations occur, such as around fast-moving machinery and robots and sources of power. In these locations injuries typically take place at points of operation and machine motion, as well as areas of power transmission, so machine designers and safety engineers must follow Occupational Safety and Health Administration (OSHA) standards to ensure safety of employees. Fortunately, a variety of safety mechanisms and devices that can be integrated into existing systems are available to improve machine safety and isolate energy sources in a way that complies with OSHA regulations and keeps your workers safe. Here, we gather information on safety devices that offer maximum protection with minimum impact on machine operations and budgets.
Lock Out/Tag Out Solutions
Just because a machine is turned off, does not mean it is in a safe state as unexpected bursts of energy can create dangerous situations for technicians performing maintenance on the equipment or operators in close proximity to the machinery. Lock Out/Tag Out devices are used to ensure that any potential energy in the machine is neutralized to prevent unintentional start ups. As one of the most common (and necessary) safety solutions, Lock Out/Tag Out mechanisms are available in several versions. Locks use a single padlock to enforce manual locking/unlocking routines before and after a machine is used. Tags employ coded colors and written details to provide visual indicators of machine status. Hasps are available for isolation points where multiple people may be required to allow operation.
Emergency Stop Devices
When there is an emergency, workers need a fast and effective means of stopping a machine or device when it becomes necessary to prevent injury or material loss. Emergency stop, or E-stop, buttons, switches, chains and ropes can be wired into equipment to override other machine controls and cut off power to hazardous machine motion. These devices are usually brightly colored and placed in easy-to-access areas.
Two-Hand Controls, Foot Pedals/Switches and Enabling Switches
These devices are used to allow operators to safely run machinery without getting dangerously close to hazards.
Two-hand control devices require an operator to use both hands to initiate machine motion without getting close to pinch points or moving parts. If one or both hands are removed from the device, the machine powers off to ensure hazardous motion is halted. This type of control makes it difficult to accidentally activate machinery, as well.
Foot pedals and switches fill the same niche in operations where hand-free operation is necessary, such as on routers, conveyors and presses.
Similar to two-hand control devices, enabling switches are user-operated solutions that engage when a user squeezes or releases the switch. They can be continuously functioning, allowing machines to be manually operated but only with an operator at the controls and can come in the form of a button or trigger on a handle.
Safety Mats and Bumpers
These contact-sensing devices are pressure activated. Safety mats are used for safe activation and deactivation of machines and devices and allow a machine to function only when a user is standing on it, while safety edges and bumpers halt motion if pressure or resistance is detected.
While physical barriers such as metal guards and cages keep employees safely away from hazardous areas, they can be space hogs. In many applications light curtains or laser scanners can be used to provide safety without compromising operations or floor space.
Safety light curtains create a sensor-based screen that guards machine access points and perimeters. If a worker or an object interrupts any beam of the light curtain, machine motion will be halted to prevent injury.
Laser scanners send horizontal signals to protect designated areas in an effort to keep employees and objects a safe distance away from active hazards. Integrated scanners will stop the process or machine if something breaches the lasers. These are an ideal solution for irregularly shaped work zones or complex processes that aren’t easily protected by light curtains.
Safety Interlock Switches
Often used in conjunction with physical guarding solutions, these safety-minded devices are designed to monitor mechanical guards that separate workers from hazards. If a gate, door or panel is opened or removed, safety interlock switches send a signal to the machine control system to stop motion of the machine or process.
Safety Controllers, Relays and Modules
These safety solutions can be used to control many of the other safeguards mentioned above to ensure safe start and stop functions on hazardous machinery. Relays and modules can control safety light curtains, safety interlock switches and safety mats. Safety controllers can be used to replace multiple safety relay units in applications that include multiple critical safety devices. A productive and safe work environment is possible when appropriate safeguards are integrated into hazardous machines and processes. It is important to consult OSHA guidelines and conduct risk assessments specific to your facility. Taking these steps and utilizing the most up-to-date safety devices and solutions will help ensure the functional safety of your workplace and keep your employees free from accidents and injuries.