Once data center design and construction are completed, and whitespace equipment is ready to go live, data center owners and operators have to confront the very real electrical hazards and risks their employees face when working alongside energized equipment. One extreme danger that all data center personnel must be prepared for is arc flash.
Though arc flashes are not common occurrences in data centers, anyone who works in the envelope must be cognizant of the risks these life-threatening incidents pose.
This is especially true in today’s modern data centers, which often feature increasingly sophisticated equipment that is manufactured to be both easy-to-use and safe. This new equipment can lead to some data center employees becoming complacent or taking unnecessary risks when working around electrical systems.
But before we dive into how data center operators can help mitigate risk and protect their employees, let’s define what arc flashes are, and why they’re so dangerous.
What is an Arc Flash?
An arc flash is an electrical fault that stems from a short circuit condition in electrical equipment which in turn creates a high-voltage arc that causes the air to ignite in a plasma explosion. The plasma produced by arc flashes can be hot enough to melt the metal in the electrical equipment that is short-circuiting.
The explosion of molten metal can inflict extreme burns on anyone who is near the flash and can lead to other very serious injuries and even death.
While these incidents are uncommon, they still happen with frightening frequency for something so dangerous and deadly. According to reports – arc flashes occur upwards of 30,000 times a year, and have led to 7,000 burn injuries, 2,000 hospitalizations, and 400 fatalities annually.
Arc flashes can occur in both higher and lower voltage environments. Though arc flashes are more severe and dangerous at higher voltages and higher amperages, whitespace workers should always proceed with caution. It’s important to remember that arc flashes occur at the same frequency, regardless of voltage levels, and employees should never approach electrical equipment with complacency – even if they are working with lower voltages.
But what can data center owners and operators do to ensure that their employees are safe from arc flash risks?
Training, equipment, and processes
It is critical that once a data center begins operations, all qualified employees have been properly trained and certified to work on electrical equipment. This education and training should include training on arc flash risk and prevention. Data center operators should also follow all requirements and guidance prescribed by the Occupational Safety and Health Administration (OSHA).
According to OSHA, both qualified electrical workers and non-qualified employees must be made aware of and follow certain policies when working on and around energized electrical equipment. The top, and probably most obvious, OSHA directives are that only qualified employees work on electrical equipment and that all equipment must be de-energized before any work begins.
OSHA then recommends different approach boundaries be established to minimize arc flash risks when employees are working on or near electrical equipment.
According to OSHA, four approach boundaries should be established: flash protection boundary, limited approach, restricted approach, and prohibited approach. OSHA defines the flash protection boundary as “…the farthest established boundary from the energy source.” The limited approach boundary is determined by “…where a shock hazard exists.” The restricted approach boundary is where an “increased” risk of shock exists, and the prohibited approach boundary is considered the equivalent of “making contact” with a live part.
OSHA’s guidance emphasizes that these boundaries are not universal for all equipment, as, “Some equipment will have a greater flash protection boundary while other equipment will have a lesser boundary.”
In addition to the establishment of approach boundaries, OSHA also recommends different protective methods be utilized. These methods include de-energizing the circuit, embracing safe work practices, and implementing safety equipment such as insulation, guarding, barricades, ground fault circuit interrupters, and grounding.
Owners and operators must also ensure that all qualified employees are equipped with and wear the proper personal protective equipment (PPE) when working on or near live electrical equipment, such as insulated gloves, arc flash-resistant clothing, face shields, and helmets.
Having all equipment labeled is also critical to arc flash protection so that both qualified and non-qualified employees understand the risks of the equipment around them. But the most important thing that anyone who owns, operates, or works in a data center can do to combat the arc flash risk is…
Never get complacent
Avoiding safety complacency is another vital part of arc flash protection. This is especially true today when electrical equipment manufacturers have worked so hard to make equipment incredibly safe and easy-to-use.
Equipment manufacturers have made strides in the ease of use, installation, and maintenance of the electrical equipment that technicians work on every day. These improvements in the safety and simplicity of equipment are beneficial and increase efficiency, but they can also create a false sense of safety and security among those who work in data centers.
Increased ease of use can lead employees who are not trained to work on electrical equipment to do things themselves that should be done by qualified electricians. Increased equipment safety should not be a signal for professionals to let their guards down, bypass safety protocols, or take shortcuts that increase the risk of arc flash.
Even with this new generation of easier-to-use, and safer electrical equipment, owners, operators, and data center personnel must remain vigilant of the extreme danger posed by arc flash incidents and should still operate under a high-risk assumption. It’s essential that any data center employee working on or near electrical equipment never gets complacent, always wears appropriate PPE, and takes all steps and procedures to mitigate arc flash risk. And, of course, the very best safety measure to avoid arc flash incidents is to completely de-energize electrical equipment before working on it.
