Do I need an arc flash study for my Calgary commercial building?

If your Calgary commercial building has electrical equipment rated 208V or higher — which includes virtually all commercial panels, transformers, switchgear, and motor control centres — then yes, an arc flash study is strongly recommended and may be legally required under Alberta's Occupational Health and Safety (OHS) Act and the Canadian Standards Association's CSA Z462 (Workplace Electrical Safety). The study identifies the arc flash hazard level at each piece of electrical equipment and determines the personal protective equipment (PPE) required for anyone who opens, works on, or works near energized equipment.

An arc flash occurs when electrical current leaves its intended path and travels through the air between conductors or from a conductor to a grounded surface. The resulting explosion produces temperatures up to 19,000 degrees Celsius (hotter than the surface of the sun), a pressure blast that can throw a worker across a room, molten metal shrapnel, and intense light that can cause permanent blindness. Arc flash incidents in commercial and industrial settings are among the most catastrophic workplace injuries — they are survivable less often than many people realize, and survivors frequently suffer life-altering burns and trauma. This is not a theoretical risk; arc flash incidents occur across Canada every year.

Alberta's OHS legislation requires employers to identify and control workplace hazards, and arc flash is an identified electrical hazard. CSA Z462, which Alberta adopts as a standard of practice for workplace electrical safety, specifies that an arc flash risk assessment must be performed to determine the incident energy at each piece of equipment where workers might be exposed. The study calculates the incident energy (measured in calories per square centimetre) at working distance for each panel, disconnect, switchgear, transformer, and motor control centre. Based on the incident energy level, the study establishes the arc flash boundary (the distance at which the incident energy drops to a survivable level) and the PPE category required for workers approaching the equipment.

An arc flash study for a typical Calgary commercial building costs $2,000 to $8,000 for a single building with a straightforward electrical distribution system. Larger or more complex facilities — multi-storey office buildings, industrial plants, data centres — can cost $8,000 to $25,000+. The study is performed by a Professional Engineer or a qualified arc flash analysis firm using specialized software (typically SKM Power Tools or ETAP). The process involves collecting data on your electrical distribution system — transformer sizes, cable lengths and sizes, breaker types and trip settings, utility available fault current from ENMAX — and modelling the system to calculate prospective fault currents and incident energy at each point.

The deliverable from an arc flash study includes arc flash warning labels that must be affixed to every piece of electrical equipment. Each label displays the incident energy, arc flash boundary, required PPE category, and shock hazard voltage. These labels are a visible, ongoing safety communication tool for anyone who approaches the equipment — your maintenance staff, visiting electricians, HVAC technicians, and building inspectors. The labels are not just a good practice; they are a CSA Z462 requirement.

Arc flash studies should be updated every five years or whenever significant changes are made to your electrical distribution system — panel upgrades, transformer changes, service entrance modifications, or utility changes. If your Calgary commercial building has never had an arc flash study and has equipment rated 208V or higher, consult with a qualified electrical engineer or your commercial electrician to arrange one. Your electrical contractor should carry WCB Alberta coverage and be familiar with CSA Z462 requirements. Find commercial electricians through the Calgary Construction Network at calgaryconstructionnetwork.com.