An arc flash event can happen in a split second. In an electrical explosion, an arc flash occurs during a fault – or short circuit condition – which passes through an arc gap. This short circuit can expel a powerful blast of energy in the form of a super-heated ball of gas, leading to lethal or disabling consequences for electrical workers. Almost all buildings contain equipment that leaves employees vulnerable to arc flash hazards, yet not all building owners fully understand these dangers.
RTM Engineering Consultants provides arc flash studies and analyses to educate building owners about the potential risks of their electrical equipment, and best practices they should implement to protect their workers. RTM recently published a guide that explains what causes arc flash hazards, and what safety measures are most effective in preventing accidents.
Read more about the basics of arc flash hazards, then download the full guide.
What are workers at risk from arc flash hazards?
Workers are exposed to arc flash hazards whenever they open live electrical panels with voltage exceeding 50V; this often occurs when they are metering or troubleshooting a problem. When an electrical explosion occurs, it produces a fire that can burn flesh at distances of 10 feet or more. Arc flash temperatures can reach as high as 35,000 degrees Fahrenheit, liquefying or vaporizing nearby metal equipment parts, and generating extreme pressure and sound waves.
What are the best protective measures against arc flash hazards?
Education about arc flash hazards is crucial for all those involved in the design, implementation, and evaluation of electrical distribution systems. The most secure way to prevent accidents due to arc flash hazards is to de-energize equipment with electrical panels before employees work on it. If this isn’t possible, then workers should receive comprehensive electrical safety training and the appropriate personal protective equipment (PPE) for the level of hazard that may occur at each piece of equipment.
An arc flash study prepares a model of a building’s electrical system, evaluating each piece of equipment to determine how much electrical energy is available. The more energy a piece of equipment has, the greater its arc flash potential and its risk to life safety. Once an arc flash study is completed, each piece of equipment should be labeled with arc flash distances and incident energy potential, so that workers know what PPE is most suitable.
Learn more about arc flash hazards and RTM’s arc flash studies; download the guide.