May is National Electrical Safety Month, an annual campaign sponsored by Electrical Safety Foundation International (ESFI), which works to raise awareness of potential home electrical hazards and electrical fire safety on the job. As we consider this month of safety, as an industry professional, what do you think of when you hear the phrase “electrical safety”?
The first thing that comes to mind may be avoiding a shock or electrocution. Some will jump to the safety of a person interacting with installed electrical equipment. Often this means following the manufacturer’s operating instructions on equipment that is properly installed, properly maintained, closed and secured doors, covers in place and secure, and with no sign of impending failure. Many in the electrical industry may think of personal protective equipment (PPE) and establishing an electrically safe work condition as electrical safety issues. Did anyone think of the design of an electrical system or of the electrical equipment itself? If so, was the equipment operator the only one considered for product liability issues or did you include the person who will maintain the equipment?
An example of designing for electrical safety for abnormal conditions is a ground-fault circuit-interrupter. For more than a century, people were being electrocuted by accidental contact with energized circuits or parts. A design group developed a device that would limit the potential of an electrocution by opening the circuit before the current level approached an electrocution risk. It is impossible to estimate the lives saved by this device. The design of electrical systems or equipment does play an important role in providing electrical safety. However, many product standards only address safety of the equipment when it is under normal operation conditions. Equipment evaluated under these standards does not typically have a limit to the voltage, current or energy level contained within the enclosure.
The risk of serious injury greatly increases when someone must open the enclosure for any reason. This must be able to be safely performed. As the equipment designer did you consider this highly probable situation? Did you design electrical safety into the equipment to protect maintenance personnel? Even when equipment is going to be placed into an electrically safe work condition (de-energized, locked out), there is a risk in verifying that all energy sources have been successfully removed. You, the equipment or system designer, can save lives by considering electrical safety for tasks conducted over the life of the installation. Sectionalizing equipment, isolating higher voltage, current or energy level circuits, providing disconnect devices in strategic locations, opting for a different circuit design, using insulated terminal blocks or designing-in mitigation systems are examples of means of providing safety for maintenance personnel. When designing an electrical system the same considerations are beneficial. A current-limiting overcurrent device, a separate disconnect box, an arc-flash mitigation device, or an energy-reducing maintenance switch are some methods of protecting the maintenance person.
A designer of electrical equipment or systems needs to consider the electrical hazards inherent in their design for anyone who might be exposed. A person is not only at risk by using the equipment but while maintaining the equipment. There are ways to mitigate the hazards and associated risks in the design. Once the equipment is produced or the system is installed the possibilities for providing protection are greatly decreased.
During National Electrical Safety Month, let’s take the time to address electrical safety in the design stage; doing so will provide protection for all and will serve to make the workplace a safer electrical environment.
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