In the UK, there does not even have to be personal injury to provoke legal action by the authorities. This comes out of the requirement to report an arc flash event under the UK Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (RIDDOR). This places a duty to report certain serious workplace accidents, occupational diseases and specified dangerous occurrences (near misses). To give an example, a formal report will need to be made of any explosion or fire caused by an electrical short circuit or overload which either: results in the stoppage of the plant involved for more than 24 hours; or causes a significant risk of death. There is a good chance of subsequent investigation and theoretically, the Health and Safety Executive (HSE) may wish to serve legal notices or even prosecute.
2.3.5 Damaged Brand Name
When I was working with a certain large electrical and mechanical contractor, it became very clear to me that a recent arc flash incident could potentially threaten the viability of their company. They were very well established and had a large blue-chip client base in the UK and beyond. Unfortunately, they were being investigated by the HSE following an arc flash incident involving an electrician who had been connecting a cable into a supermarket main switch panel out of hours. I was engaged by them to help them to put in place policies and procedures which should have been in in force in the first place to prevent anything like that happening. It was a bit like shutting the stable door after the horse had bolted. Senior management spent countless hours in investigations, discussions and legal representations to mitigate against the threats that a prosecution under the Health and Safety at Work Act would mean for them. From my experience as a former electrical contractor and also as a client I realised that once a prosecution had been secured, the company would have to declare that fact for every pre-qualification that they would have to complete, either for new works or for ongoing maintenance of existing contracts. When I worked as a client, I would find it extremely off-putting to see a pre-qualification from a prospective electrical contractor which declared a failure to demonstrate adherence to their own core competence criteria. The pre-qualification process is very much centred around the contractor being able to demonstrate that core competence. My message to contractors is to be mindful of the damage to your brand that could occur when working on energised equipment.
2.3.6 Severe equipment damage
I give several examples in this guide of damage to electrical equipment which has required complete replacement due to the effects of arcing. Replacement of electrical switchgear carries a high price tag not only in cost but procurement time and outages. Repairs are not often possible due to lack of replacement parts. I did some research some time ago on the age of high voltage electrical equipment in service in the UK in industrial/commercial sites. Over 40% of equipment was over 20 years old and 20% over 30 years old so there was likely to be a high level of obsolescence. I was staggered to find that there were switchgear and transformers still in service from before World War 2. (Sample size 1200 industrial and commercial sites in an estimated total of 26000 sites)
2.3.7 Lost Production
Very often the reason cited for working on live equipment is that production is so important that it would not be possible to shut the equipment down to work on it safely. I am not saying that continuity of production is not a valid reason in every circumstance, but I would say that it is not a valid reason in most circumstances. Having a shutdown in a planned way will stop production for the duration of the work whereas having an electrical flashover in switchgear will result in an unplanned event. In most cases, it is not going to be possible to resume production in a reasonable amount of time if the damage is severe because of the points made in my previous paragraph. It is for the business concerned to determine the risk through a proper risk assessment and there are the tools here to provide a measure of severity should things go wrong as part of that assessment.
2.3.8 Fires
In recent years, the subject of arcing appears to have been concentrated on the protection of an individual standing in front of energised equipment. As a result, the debate has been polarised around personal protective equipment. What we sometimes forget is that arcing is responsible for huge losses due to electrical fires and I was staggered by the statistics. In England alone in the year 2018/19 there were 4199 fires in non-domestic premises where the source of ignition was named as electrical distribution and a further 1826 fires attributable to other electrical appliances. The majority of non-domestic fires that were specified as having “non-human factors” were in fact from electrical distribution causes. I would estimate that most electrical fires are the result of electrical arcing. (Source UK Home Office)
2.3.9 Environmental Impact
As indicated previously, the justification for carrying out live work is often influenced by the essential nature of the equipment which is being serviced. For instance, a 24-hour production facility which will require some planning in order to de-energise the electrical system. What I have established is the severe consequences of an arc flash event. The same mindset of preserving power at all costs could be applied to processes that rely on power to protect the environment. There are many obvious examples in the water industry such as treatment plants and storm sewage pumping stations or the nuclear industry, but also right across industry wherever power is required to control potentially environmentally damaging processes. In my Chapter 12: Myths and Mistakes, I give the example of an arc flash event whereby a serious situation was narrowly averted when polychlorinated biphenyls (PCBs) could have been discharged into a water course following an electrical flashover in a high voltage capacitor. As always, the safer option of a planned outage is preferred to an unplanned event following an expedient quick fix repair under live conditions.