Arc flash exposure: are you really doing enough?

Since 2010, between four and nine electrical workers have lost their lives in Australia each year while on the job, with another one to two hundred presenting in emergency rooms suffering electricity-related injuries. These numbers remain static year in, year out — why is this still happening?

It’s no secret that working on electrical equipment poses risks. Thomas Edison figured that one out back in the 1860s. Oddly enough, the development of electrical standards owes more to the insurance industry than anything, where concern over fire hazards in buildings was the big driver for the emergence of rudimentary circuit breakers, current limiting fuses and a voltage-presence testing device. These designs were gradually supported by a range of procedures and guidelines which became recognised as the first formal National Electrical Code in the United States.

So, you are familiar with all the rules, have implemented a safety program of sorts, observe a ‘no live work’ policy and every employee travels with a van full of PPE. In other words, you’ve got it covered when it comes to potential electrical injury, right? Maybe… and then maybe not.

It’s not as though the prevailing attitude is ‘near enough is good enough’ when it comes to electrical safety. You won’t hear an employer saying “I’m about 75 to 80% sure that no-one will die today based on our policies and procedures” and it’s difficult to imagine any employee intentionally cutting corners when their own safety is at risk — not when the stakes are this high. How then, can we explain the unchanging rate of death and injury among electrical workers in Australia year to year?

Four, five or 10 deaths annually may not seem substantial in terms of overall numbers, but the truth is that even one fatality a year is too many when you consider these incidences are almost always preventable.

Increased exposure

Maybe it’s as simple as the changing nature of the work being carried out. According to the National Electrical and Communications Association (NECA), “The proliferation of solar panels, energy storage and uninterrupted power supplies (UPS) used in industrial, agricultural, commercial building and even the residential sector increases the risk of exposure to safety hazards that are inherently associated to nonlinear power sources. With more complicated systems being installed increasing the likelihood and severity of an electrical arc flash the need for a systematic approach to managing occupational health and safety in the electricity industry is needed more than ever.”

In addition, NECA highlights that the use of larger transformers to power residential installs means that short-circuit currents are much higher than they used to be.

Arc flash, in particular, has been an increasing focal point within the industry in recent years. Given the associated risks, it’s little wonder. Arcs can cause substantial injury — internally and externally — and additionally create an environment where circuit protection is rendered useless.

In June this year, an underground worker in Western Australia sustained burns when he was performing wiring modifications to a 415 VAC motor control centre. During the work, an incorrectly positioned busbar cover panel came into contact with fuse-holder bolts which were protruding from energised busbars behind the cover panel. The resulting arc flash and blast resulted in burns to the worker’s hands and arms, and it was subsequently established that the worker was not wearing adequate PPE for the amount of energy released.

Isolating the issues

A 2015 report from the National Fire Protection Association in the United States found that the biggest contributing factors to electrical injuries are:

• work inappropriately performed on energised equipment;
• insufficient training for working on or around energised electrical equipment; and
• failure to use appropriate personal protective equipment for electrical safety work practices.

While the causes may have been identified, it doesn’t explain why practices and procedures are lagging behind the potential dangers.

In response to the changing landscape and to combat the number of incidents, NECA developed a toolkit of information and resources titled ‘An easy guide to arc flash analysis’.

The guide draws attention to WHS Regulations 158 and 161, which both state that “if electrical work is to be carried out on energised electrical equipment an electrician must ensure that risk assessment is carried out by a competent person who has tools, testing equipment and PPE that are suitable for the work and have been properly tested and are maintained”.

The guide further clarifies working on energised electrical equipment as any task that includes:

• isolating
• switching
• removing fuses or links
• isolation verification (testing for dead)
• testing
• fault finding
• ‘live’ work

As NECA points out, these are all pretty fundamental tasks in the average electrician’s working day. The association suggests that a ‘no live work’ policy can’t possibly exclude all circumstances where electrical hazards exist. This means that an effective risk assessment is the best possible weapon in your armoury in the fight against worker injury, yet one that many still be deemed too difficult or time-consuming to undertake.

According to the Safe Work Australia Code of Practice ‘Managing Electrical Risks in the Workplace’ published February 2016, it’s a very straightforward process:

1. Identify hazards.
2. Assess risks associated with those hazards.
3. Implement and maintain risk control measures.
4. Review those risk control measures.

As NECA outlines, this process forms part of an overall Electrical Safety Program (ESP), which every electrical contracting business should have in place. The ESP should also include provision for training and utilising appropriately rated PPE, as well as ensuring that workers have the tools for the job. The organisation specifically mentions that all clothing should be flame resistant.

The arc analysis guide says that a good risk assessment process must incorporate a calculation of incident energy, which is then used as a basis for selection of appropriate PPE and controls. Anecdotal evidence — the number of reported arc flash incidents — suggests that this process may be underutilised in the electrical industry.

NECA suggests that many electrical workers are daunted by the prospect of an arc flash calculation and that the procedure may be bypassed as a result. It concedes that to derive complete accuracy involves complicated calculations but suggests that a basic calculation for the purposes of determining safety is much easier than you’d think.

To that end, NECA developed a calculation tool which can be accessed directly from the association’s website (http://neca.asn.au/nsw/content/guide-arc-flash-analysis), where you will also find an outline of the steps required to ensure that you are selecting the appropriate PPE for the job, along with a sample ‘Arc Flash and Shock Hazard Appropriate PPE Required’ label. Download the label for application to the board or equipment being worked on, which can be used as a reference next time or for when others need to make the same choices on appropriate PPE.

All PPE is not created equal

In November 2015, workwear manufacturer Hard Yakka PROTECT conducted a survey of Australian workers from industries where exposure to arc flash was common. The purpose of the study was to ascertain attitudes towards (and use of) workwear that incorporated flame resistance technology.

The results were shocking, as they indicated that more than one-quarter of respondents (28%) did not wear flame-resistant clothing, despite the inherent risks from arc flash. The reasons were varied — from employers not providing this type of PPE through to discomfort and high cost, none of which seem particularly valid when you consider the possible alternative outcomes.

Flame resistance matters

Aside from the obvious fundamental dangers of arc flash, electing not to utilise suitable flame-resistant workwear further compounds the issue. The initial flash or blast is only half the problem if your clothes catch on fire. Check out some of the videos available on YouTube if you don’t believe us.

Regular clothing, such as cotton or poly/cotton blends, will simply not do the trick. Similarly, supplying PPE to only the minimum required level or assuming that workers are utilising it properly is not enough.

The SWA code of practice points out the limitations and gives an idea of where the buck stops:

“PPE includes protective eyewear, insulated gloves, hard hats, aprons and breathing protection. The PPE should be rated for the work to be done. If working on energised equipment, the PPE must be able to protect the user from the maximum prospective energy available at the work site. Administrative controls and PPE do nothing to change the hazard itself. They rely on people behaving as expected and require a high level of supervision.”

This presents another problem — if the equipment supplied is too cumbersome, limits movement, decreases dexterity or is deemed just plain uncomfortable, then the temptation to remove it will probably win out, regardless of the risks.

Acknowledging accountability

In July this year, a contracting firm was fined $60,000 for failing to ensure electrical equipment under their control was adequately maintained, in relation to an incident that occurred three years prior. The Department of Mines and Petroleum Mines found Contractor Crushing Services International was responsible for injuries sustained by an electrician in its employ.

The worker was replacing components in a switch room and was exposed to live conductors due to the lack of a barrier preventing contact with live terminals. He suffered severe burns as a result of the arc flash that followed.

In early September, Essential Energy was fined $300,000 for failing to comply with its duty of care for workers, following the death of a 47-year-old man in 2013.

The man was electrocuted when an electrical conductor he was holding became re-energised as it came into contact with, or in proximity to, energised overhead conductors while it was being lowered to the ground.

SafeWork NSW’s investigation found that while Essential Energy was aware of the risk of keeping the top conductors energised while workers removed the bottom conductors, it chose to keep them energised for service delivery reasons.

The investigation determined that if Essential Energy had ensured the top conductors were de-energised and the power was turned off at the feeder, no power could have come onto the worksite and the incident could have been prevented.

These are only two of the most recent examples of safety breaches. Sadly, both could easily have been avoided.

When it comes to electrical safety, there is simply no excuse for cutting corners or failing in your duty of care. As an industry, we should be aiming for zero fatalities, particularly when it is within our power to prevent injury and death simply through adherence to established processes and procedures.

Image credit: © Serg Nvns/Dollar Photo Club