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Arc Flash and Fault Level Assessment
Covol Engineering provides specialist Arc Flash and Fault Level Assessments for industrial and commercial electrical systems across the UK and globally. Our electrical engineers use detailed system data and SKM Power Tools modelling to calculate fault currents, assess Arc Flash hazards and provide practical recommendations to improve electrical safety.
With well over 1,000 Arc Flash studies completed for major clients across aerospace, engine production, chemical manufacturing and pharmaceutical manufacturing, Covol combines detailed electrical engineering analysis with clear, site-specific reporting.
An Arc Flash is a release of electrical energy that can occur when an electric arc forms within an electrical system. An Arc Flash incident can produce intense heat, bright light, sound, molten metal and a pressure wave, creating serious Arc Flash hazards for electrical workers and nearby electrical equipment.
The energy released during an Arc Flash incident can cause severe burns, equipment failure, electrical fire and serious physical injuries. The severity of the Arc Flash hazard can be influenced by fault current, voltage, protective devices, equipment condition and the time taken to clear the fault.
An Arc Flash fault occurs when electrical current leaves its intended path and travels through the air between live conductors, between phases or between a conductor and earth.
An arc fault describes the abnormal arcing condition. Arc Flash describes the heat, energy and force that can be released when that arc fault develops within high-energy electrical equipment.
When an arc fault occurs, understanding the available fault current and how quickly protective equipment operates is essential to assessing the potential Arc Flash incident.
Series arc faults and parallel arc faults may also be discussed in relation to arc fault protection devices in low-voltage electrical installations. These devices can help address certain electrical fire risks in suitable applications, but they do not replace a full Arc Flash and Fault Level Assessment for higher-energy industrial or commercial electrical systems.
Fault level is the amount of fault current that could flow through an electrical system during a short circuit, earth fault or other abnormal fault condition.
A fault level assessment helps establish whether circuit breakers, switchboards, cables and other electrical equipment are suitably rated and whether protective devices can interrupt fault currents correctly.
Covol uses industry-standard SKM Power Tools software to model the electrical distribution system using equipment data, protection details and cable impedances. Our engineers can then compare calculated fault levels against equipment ratings, manufacturer information and relevant standards.
Fault level shows how much current could flow during a fault. Arc Flash analysis then considers how the fault current, clearing time, equipment arrangement and working distance affect the energy released during an Arc Flash incident.
If available fault current is misunderstood, the Arc Flash hazard can also be misunderstood. This can affect Arc Flash boundaries, personal protective equipment recommendations and opportunities to reduce risk.
A combined Arc Flash and Fault Level Assessment gives duty holders, facilities teams and electrical engineers practical information on:
Arc Flash hazards can be influenced by system energy, equipment condition and human interaction.
Contributing factors identified within Covol’s existing assessment process include:
Understanding these potential risks requires the wider electrical system to be considered rather than looking at individual electrical equipment in isolation.
Our Arc Flash assessment can include:
If complete electrical records are unavailable, Covol can advise on the best way to proceed before the Arc Flash study begins.
Accurate Arc Flash analysis depends on reliable electrical system data.
Covol may review incoming supply details, transformer data, switchgear ratings, cable sizes and routes, circuit breaker details, protection settings, fuse and relay data, distribution board schedules, electrical loads, asset information and existing protection coordination data.
This allows our electrical engineers to calculate fault currents, assess Arc Flash hazards and provide recommendations specific to the electrical system being studied.
Arc Flash risk should be reduced at source wherever possible. Appropriate PPE is important, but personal protective equipment should not be the only control measure.
Depending on the assessment findings, Covol may recommend reviewing protection settings, circuit breaker performance, protection coordination, electrical equipment, switchgear condition, incident energy, warning labels and safety-related work practices.
Where higher-risk areas are identified, our Arc Flash Mitigation service can assess practical options for reducing Arc Flash risk and improving electrical safety.
Covol has completed well over 1,000 Arc Flash studies for major industrial and commercial clients. Our experienced electrical engineers combine fault level analysis, electrical system modelling and practical reporting to help clients understand the Arc Flash hazards within their installation.
We do not simply provide calculations. Our reports explain the findings, identify areas requiring attention and provide practical recommendations covering equipment, protective devices, warning labels, PPE and Arc Flash mitigation where required.
Learn More About Covol and explore our recent arc flash case studies:
If your electrical system has not been assessed, has recently changed or you are unsure whether existing Arc Flash and fault level data remains accurate, Covol can help.
Fault level is calculated by reviewing the power supply, transformer impedance, cable impedance, voltage, earthing arrangement and connected equipment. For commercial and industrial systems, engineers use specialist modelling software to calculate accurate fault current values across the network.
No. An arc fault is the abnormal arcing condition. An arc flash is the release of heat, light, pressure and energy that can result from an arc fault in an electrical system.
Arc flash usually refers to the heat and light produced by an electrical arc. Arc blast refers to the pressure wave and force that can occur when the arc rapidly heats air and vaporises metal. Both can be dangerous during an arc flash incident.
Arc fault detection devices can help detect certain arcing faults in suitable low-voltage installations, particularly where electrical fire risk is a concern. They do not replace a full arc flash and fault level assessment for industrial or commercial electrical systems.
Arc flash and fault level assessments are important for organisations operating complex or high-energy electrical systems.
This includes manufacturing sites, chemical and pharmaceutical facilities, aerospace and engineering facilities, power generation and distribution environments, industrial plants, large commercial premises, sites with ageing or modified electrical infrastructure, facilities planning major electrical changes, and organisations reviewing electrical safety or insurance requirements.
An assessment is especially valuable after network modifications, equipment changes, protection setting changes, capacity increases or incidents involving electrical equipment.