Although thankfully rare, arc flashes pose an extreme risk to those working on or near live conductors. In the UK alone, thousands of people are taken to hospital with severe burns as a result of exposure to an arc flash over a 12 month period – there are even several fatalities every year.
In Proactive Technical Training’s “Arc Flash Hazard Safety” course, students will be introduced to the key issues surrounding Arc flash hazards giving them the knowledge and the insight needed to be able to anticipate potential occurrences of Arc flashes and how to prevent them.
In this article, we’ll take you through:
- What an arc flash is
- What effect an Arc blast has on an organisation
- How to provide staff with a safe environment
- Details on the PTT Arc Flash Hazard Safety course.
What is an Arc flash?
An Arc flash describes the unwanted movement of an electrical charge through the air between two conductors or the earth. If the voltage between the conductors is high enough and/or the atmospheric impedance is low enough then an arc flash may occur, and once underway the super heating along the path of the flash further lowers atmospheric resistance which makes even more current flow. Eventually, and within a fraction of a second, this release of energy results in an electrical explosion.
There is no warning prior to the occurrence of an Arc flash so there is no time for people who will be affected by one to remove themselves from danger. The Arc flash generates a significant force (1,000s of pounds per square inch) that can damage internal organs, eyes, lungs, and eardrums and which can literally knock people off their feet.
There is a major risk to victims’ eyesight because of the extremely intensive flashes of light. Workers in the vicinity of an Arc flash may experience long-term or temporary vision issues if their eyes are not sufficiently protected.
The explosion from an Arc Flash is known as an Arc Blast, and can shatter the conductors from which the Arc flash originated causing a risk of injury or death from the resulting shrapnel. Depending on the conditions which created the Arc flash, temperatures in the very near vicinity of the arc blast can rise to 35,000oF, enough to cause serious or fatal burns to people in the nearby area.
What effect does an Arc blast have on an organisation?
Arc flashes are considered as major health and safety incidents so it is highly likely that, in the first instance, your premises and working practices will be subject to a thorough assessment from the Health and Safety Executive. UK Power Networks received a heavy fine following the death of an employee in an Arc flash in 2013 (source: E-hazard). Four years earlier, an electrical supervisor died in an arc flash at the ConocoPhillips terminal in Seal Sands (source: Northern Echo).
As well as the potential financial penalties that a company is exposed to with an Arc blast fatality incident, there is the certainty that their colleagues will be traumatised by the loss of a fellow employee. This, at a minimum, will significantly affect the company in many ways in the short to medium term.
When an incident does not prove fatal, there may be a significant risk to productivity if the member of staff who is injured or the equipment damaged is critical for the functioning of a business.
Providing workers with a safe environment
While the occurrences of Arc flashes can not be accurately predicted, there are a number of steps that can be taken to minimise the risk of injury or death to staff, visitors, and customers.
First, someone in the business should be trained in safe working practices regarding the potential risks of Arc flashes. What is considered by the Health & Safety Executive to be the current safe working practices for Arc flash risk minimisation is available to read in the organisation’s “Electricity at Work: Safe Working Practices” manual.
You or the responsible member of staff should understand how power is currently distributed around your premises (particularly for Arc flash hazards) and, in areas of risk, staff should be properly equipped with PPE. PPE that should be considered includes arc flash hoods, flame retardant overclothing, arc flash gloves, face shields, and arc suppression blankets.
You should also make sure the company keeps up to date with recent technology including arc limiting fuses and remote racking equipment. Where it is possible to install such equipment, it would be beneficial to conduct a feasibility study to determine whether there is a case to purchase and install it.
Working practices should also be investigated to find ways to reduce the risk of an incident and the level of energy that could be released if an incident was to occur. It would be prudent to improve risk awareness of staff, visitors, and customers, as well as to update any current safety procedures to take account any newly discovered risk.
When repair or maintenance work is due to start on high-voltage equipment, it should be de-energised prior to the commencement of work. Procedures for doing this should be regularly reviewed and incorporate multiple steps to check that no electrical energy remains in the working environment.
If you feel that protection within and outside of your work premises against Arc flashes should be updated and improved, please contact us about our Arc Flash Hazard Safety Course for more information.
Contact us about our Arc Flash Hazard Safety Course
Proactive Technical Training’s next Arc Flash Hazard Safety Course is being held at our Tring campus on 6th June 2019. Leaners spend the entire day with us from 9am to 5pm.
The course covers the following topics:
- Legislation, Guides and Standards
- Terminology
- High Energy Electrical Safety
- Arc Flash
- Arc Flash energy
- Incident Energy
- Arc Blast
- Arc Flash Boundary and Labels
- Hazard Risk Categories (HRC) and PPE
- Risk Analysis
- Responsibilities and Reporting
- Assessments
Upon successful completion of the course, learners will be presented with a “Statement of Attainment”. This statement confirms that the learner has been assessed by their trainer as being fully cognisant of the requirements need to perform work duties safely in areas where Arc flashes present a risk.
To find out more about Arc Flash Hazard Safety Course, please contact us on 01442 828754. Or email info@ptt-training.co.uk.
Alternatively, if you wish to book onto our 6th June 2019 course in Tring, please click here.
Also, coming soon will be the availability to take our on-line e-learning version of the course.
