A Review of Arc Flash in 2023
A look back at developments and news in the world of Arc Flash during 2023.
Contents
NFPA 70E 2024
In May the National Fire Prevention Association (NFPA) published the 2024 edition of their Standard for Electrical Safety in the Workplace, known as NFPA 70E. The publication of this early, in 2023 rather than 2024, is because the changes were generally minor and there was no protracted comment and review process. Many of the changes are tidying up the structure of the document and changes to definitions, e.g. the term "shock" has been changed to "electric shock" throughout for clarity.
The technical changes in NFPA 70E are primarily a result of public comments made by the USA's Department of Energy regarding specific electric hazards. This has resulted in some changes to Chapter 3 (Safety Requirements for Special Equipment) of NFPA 70E relating to equipment like Batteries, Lasers and Capacitors.
The NFPA provide free online access to NFPA 70E and their other standards through their NFPA Link site.
Canada's equivalent document, CSA Z462, is still in draft and is intended to publish in 2024. CSA Z462 was once very closely aligned with NFPA 70E, however, this forthcoming revision has some more impactful changes as it starts to diverge from NFPA 70E. One of the biggest changes is to the Arc Flash PPE categories. Canada is introducing an Arc Flash PPE category 5 with a minimum cal/cm2 value of 75, recognising that arc flash materials and clothing continue to advance and come with higher and higher ATPV ratings. We will cover other major changes in CSA Z462 following its release.
IEC (BS EN) 50110-1: 2023
At the end of July the new version of BS EN 50110-1 "Operation of electrical installations - General requirements" was published. The last update was in 2013 and, like the changes to NFPA 70E, changes in the 2023 revision are both editorial and technical in nature.
This is a harmonised standard, intended to be used across Europe with each country adopting it. This means that it is necessarily a high-level document and, in the UK, the Electricity at Work Regulations 1989 and supporting guidance typically provide more practical and relevant information for Duty Holders and those involved with work on or near electrical systems. BS EN 50110-1 is a standards document, and not a complete set of electrical safety rules; it can be used to audit existing safety rules for suitability, or as the basis for developing a new set.
Some of the changes made in the 2023 revision include:
- Responsibilities - roles and responsibilities are now more clearly defined. Previously a role was defined by describing the responsibility. In the new revision the role is specifically named and these names are then used throughout the document. As an example: previously a role was defined as the "Person responsible for an electrical installation". That role is now termed the more concise "Installation Manager". In UK terms this would be the equivalent of the "Duty Holder".
- Distances for safety - the new revision expands and gives further guidance on defining safe working distances.
- Dead working - several changes made to this section including permitting the use of remote control devices as a Point of Isolation and making reference to the recent IEC 62271-213 for Voltage Detection and Indication Systems for medium voltage switchgear. Guidance for verifying the absence of voltage on DC systems has also been added.
BS EN 50110-2 "Operator of electrical installations - National annexes" has also been revised in 2023. This identifies relevant national legislation and standards (in Clause 34 for the UK) and these remain the primary legislation governing work on electrical systems in each country.
There was one major arc flash incident in the UK that went to court in 2023 as well as a high profile prosecution in Australia and an OSHA citation in the USA.
Global Energy Nigg Asbestos Survey
In December 2020 an asbestos surveyor, Christopher Earley, was injured by an arc flash whilst surveying an electrical panel in a disused part of Global Energy's Nigg Energy Park workshops on the Cromarty Firth in northern Scotland.
Mr Earley did not realise the panel contained live circuits: the switchroom itself was not kept locked to prevent unauthorised entry and the switchboard had no warning labels or indications of any kind.
Mr Earley suffered from extensive burn injuries to his face, right arm, right chest and left hand. He was treated in hospital but suffered from multiple infections and other complications brought on by the burn injuries. He sadly died three months after the incident.
Global Energy Nigg Limited pleaded guilty to breaching Section 3(1) and Section 33(1)(a) of the Health and Safety at Work etc Act 1974 and were subsequently fined £80,000 at Tain Sheriff Court on 18 January 2023.
Yallourn Power Plant, Australia
After a prolonged investigation and subsequent court case, EnergyAustralia, the operator of the Yallourn Power Plant in the state of Victoria, were fined $1.5 million (AUD) over the 2018 death of Graeme Edwards.
Mr Edwards was racking a 6.6kV breaker back into service following routine maintenance when the metal control umbilical dropped into the mechanism and caused an arc flash. Mr Edwards, who wasn't wearing arc rated PPE, reportedly suffered burns to 90% of his body and died a day after the incident.
The investigation found that a cover designed to prevent the umbilical dropping into the circuit breaker was not fitted and that workers were not being trained to follow the manufacturer's recommended racking procedure.
EnergyAustralia pleaded guilty to three charges of failing to provide a safe working environment.
Sources:
Beacon Hill Arc Flash, Boston, USA
Eversource Energy, a residential energy provider in the northeast of the USA, were cited for over $300,000 in January 2023 for the death of an electrical worker, Fabio Pires.
Maintenance work was being completed in an underground electrical vault in July 2022. As Mr Pires set equipment back into place an arc flash and blast occurred within the confines of the vault. The worker suffered severe burn injuries which proved to be fatal.
Investigators from OSHA found that Eversource did not fully deenergise the equipment prior to undertaking maintenance, failed to adequately determine the heat energy (Incident Energy) that a worker could be exposed to should an arc flash occur, and did not provide adequate training or rescue equipment to make work in a confined space as safe as practical.
This case remains open with OSHA and so the final outcome may still change.
Sources:
Fort Worth, Texas, USA
Four electrical workers were injured, one seriously, by an arc flash in a low voltage panel that occurred at some point during an isolation and testing for dead operation. The panel door was open and a multimeter was to be used to check for absence of voltage. The low voltage panel was part of an older area of a school site that was undergoing demolition.
The electrical superintendent who was closest to the arc flash was hospitalised with 2nd degree burns to his hand and face.
Multiple Injured PersonsCyxtera Data Centre, Boston, USA
An arc flash occurred in a battery cabinet within the main power distribution switchroom of an important data centre in Boston. The arc flash led to a fire which resulted in the fire department responding. They needed the entire power system switched off to deal with the incident and this resulted in a country-wide outage of Oracle web services. A security guard on routine patrol in the room suffered from smoke inhalation but there were no injuries directly caused by the arc flash.
Equipment DamageDelaware Dynamics, Indiana, USA
An 85 year old electrician, working for a die cast mould manufacturer in Indiana, suffered from an arc flash in March 2023 whilst removing a 480V plug-in “flex-a-plug” circuit breaker with the switchboard still live. The electrician suffered serious burns to his upper body which proved to be fatal.
FatalityIsle of Wight, UK
Two electrical explosions at a substation, the second one caught on camera, led to a large power outage effecting around 2,000 home and businesses in Ryde, the largest town on the Isle of Wight.
A few weeks earlier, an "electrical explosion" blew the lid off an electrical supply box in Ventnor, also on the Isle of Wight.
Equipment DamageBrooklyn, USA
Three construction workers were injured by an arc flash at an LV supply cubicle whilst working on a construction site in Brooklyn. CBS News reported it as a fire triggered by an electrical arc, and a post on Reddit a few days later confirmed it was an arc flash. All three were hospitalised with the most severely injured worker placed into a medically induced coma. By the end of August he was expected to recover.
Multiple Injured PersonsRTE Substation, Aubin, France
A likely arc flash caused an explosion at a substation in south-west France in August. The initial explosion injured five technicians who were all taken to hospital, and led to a power outage effecting 90,000 homes in the area. The site is operated by Réseau de Transport d'Électricité, known as RTE, the electricity transmission system operator of France. They promised an investigation into the causes.
Multiple Injured PersonsPrescott, Arizona, USA
In August an electrical worker was injured by an arc flash whilst working on a fuse panel serving a retail store in Prescott, Arizona. The worker suffered second and third degree burn injuries to his upper body and had to be airlifted to a specialist burns unit in Phoenix.
Photos accompanying the report show a small, fused isolator with fuses removed. There is evidence of a highly energetic arc flash on the surrounding cubicles and on the inner door of the electrical panel.
Injured PersonRailway Workers, Boston, USA
Two workers fixing signalling on Boston's public transport system suffered from arc flash injuries when a cable they were working with touched the live third rail. One of the workers suffered burns to the hands, requiring hospital treatment.
Multiple Injured PersonsSoap Lake Substation, WA, USA
An arc flash at a public electrical supply substation in Washington in October 2023 led to the need for a temporary substation and re-routed power to avoid disruption. Reporting indicates that the arc flash occurred somewhere between a transformer secondary and the feeder circuits. The heat released led to the vaporisation of an aluminium bus and an overpressure release of transformer oil that then ignited. Investigation work found that a critical battery system which should have de-energised the substation was faulty and did not act as intended.
Note: this local news article is not accessible to those outside the USA.
Equipment Damage
Skanwear - Global Electrical Safety Conference, Doncaster (UK)
We attended the first Global Electrical Safety Conference, held by Skanwear over two sunny days in May 2023. It featured interesting industry talks covering a range of electrical safety topics, and there was plenty of engaging discussion both within sessions and during breaks. Interesting talks included:.
- Graham Hogg (Exeltech Ltd) speaking about how he handles working on different client sites with different conditions and levels of information available. He talked about how he assesses and mitigates risk and how he treats his arc flash PPE as a uniform.
- Manoj Edathodi (Health and Safety Manager for Az-Zour North Operation and Maintenance Company) presented details of a 415V arc flash incident that had occurred at the Az-Zour North One Power Plant in Kuwait in April 2020. The injured party suffered from serious burns requiring two weeks hospital treatment. The arc flash occurred whilst a work party was racking in a large motor starter module into a live switchboard. Edathodi presented equipment modifications that have been made to address the causal factors.
- Allan Wallice (Global Electrical Safety Manager for ABB) presented how ABB have worked to develop and implement a Global Electrical Safety Programme, taking into account electrical hazards and the available standards, and developing an approach that can work across different countries and cultures.
Safe Arc Solutions - ETAP Digital Conference
We presented a talk on the topic of updating Arc Flash Studies to the latest edition of IEEE 1584 and taking advantage of some of the helpful features in ETAP. The talk can be viewed on YouTube.
ETAP - ETAP Digital Conference
ETAP's Albert Marroquin provided an insightful talk at the Digital Conference on the subject of using IEC Short-Circuit standards as input to IEEE 1584-2018 Arc Flash analysis. This talk is also available for viewing on YouTube.