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The Region's Only Industrial Health and Safety Magazine
The Region's Only Industrial Health and Safety Magazine
by Laura Steenkamp
The cost of non standardisation across countries has a detrimental effect on electrical safety. What I am going to suggest will sound insignificant, but it was significant enough to cost somebody’s life. We will first look at how standardisation can be achieved, and then how to start achieving it.
Over the course of working in the electrical industry I have come to the realisation that standardisation is the key to any successful implementation of safe electrical protocols and procedures. These electrical protocols and procedures usually come in the form of an Electrical Safety Programme, training in the classroom or/and on the job, and PPE, but more than likely their prioritisation is PPE, then training, and only if there is an audit then an Electrical Safety Programme. I can almost hear the collective gasp, but chances are that you know or have at least come across an employer that operates this way. This means that in these environments there has been very little room for standardisation, since the programme comes as an afterthought.
“standardisation is the key to any successful implementation of safe electrical protocols and procedures”
The electrical industry is a very unforgiving industry. I have had a couple of incidents where I have shocked myself; these were mostly doing household chores. Sometimes I forgot to turn off the breaker, or due to a lack of experience (aged 10) I changed a plug and tested it first, by placing it in the socket without its cover on, just to see if I did it correctly. I’d switched off the plug socket, thinking that I would not receive a shock. I was wrong.
When looking at safety pyramids, every 300 recordable injuries across industry in general result in one fatality. That’s one too many, of course. Figure 1, however, shows the ratio of recordable injuries to every one fatality for the electrical industry: there is a stark difference between 300 and 10. So how can we improve this figure? How can we expand the base to give electrical workers a better chance at survival?
The proper way to out engineer electrical shock or arc flash risk is to start at the engineering phase. The hierarchy of hazard controls starts at equipment design and eliminate the risks, then moves on to substitution, engineering controls, awareness, administrative controls and finally PPE (as suggested by the NFPA 70E).
We are going to explore standardisation as one possible solution. This is not to force market monopoly, but more to create a “herd immunity” to incorrect practices, shortcuts and at risk behaviours. The collective mentality for electrical work should be:
This should be a universal mind-set and electrical workers should have the freedom to remove any distractions when they are busy working.
How can one standardise equipment design with so many manufacturers and options available. The last thing a manufacturer wants to do is copy another, so the only area where standardisation can possibly happen is with the safety aspect (or rather philosophy) of the equipment.
Let’s look at the switchgear boards. If all manufacturers standardise on the name placing of the boards, then all engineers and technicians in the field do not have to look around to positively or negatively identify the board they have to work on. This is not a competitive edge over another manufacturer, since it does not affect the proprietary information of the design. It does, however, greatly impact the safety of the user. Incorrect identification of boards has caused fatalities in the past.
Another suggestion is the placing of an LED that is another visual tool to determine if the board is still energised. By placing the LED in, for example, the top right hand corner, all involved can see that if the light is still burning red, then the board is energised. Now what about if the LED fails? Well, then we can choose to light up the LED if the board is switched off. That way it has to be assumed energised if the light is off. This does not replace the test before touch practice at all. It just adds another layer of risk mitigation for individuals who are more visual than theoretical.
If, for example, you open the panel door and you can come into contact with live wires inside of the door, then there should be a contact barrier put in place as a minimum standard. This will save any person who inadvertently touches the live wires with either their hands or tools.
For existing installations that are not yet obsolete, or for installations that have an increased risk of electrical shock or arc flash exposure, substitution is the ideal method of risk mitigation.
This can come in the form of MCBS that are less easily bypassed as opposed to fuses. Talking about fuses, they have to be replaced with the same kind and rating. I have seen installations where a 20A fuse has been replaced with a 25A one, since “the fuse always blows”. There was no engineering, no investigation why, and definitely no mark-ups on the drawings. This is fatal behaviour.
When it is determined that by substituting the fuse with an MCB the circuit is interrupted faster, then it is the preferred choice. The standardised approach could yet again be the method of determining these types of incidents and the way they are replaced.
I am a firm believer in not re-inventing the wheel. In my previous article, I mentioned a database and how it could be used to improve electrical safety. This would be a perfect place to implement the benefits of this database. For example, if a given supplier or equipment manufacturer identifies an area of substitution to improve safety, a standard document can be issued to all end users, rather than every end user waiting to find out if there is room for safety improvement.
Sufficient engineering controls can eliminate substantial risk if applied consistently and correctly. Engineering controls can take the form of barriers and other safeguarding techniques. The method of barricading can be standardised as well as the colours. Clearly showing that there is electrical work being carried out on site (e.g. instead of civil work).
By creating a culture of “no barricade – no work”, technicians will start to be more safety aware when they walk into a substation. By seeing the standardised tape for electrical work, they can clearly identify where not to be or where to tread carefully.
Plenty of fatalities have occurred due to barricading issues. One common mistake is at the back of the boards, where users mistake similar looking boards and open them in error. By marking the boards on both sides of the “isolated” board, it creates a clear visual barrier of which is live and which is isolated.
Awareness can be standardised in the form of training received or in the frequency with which training is received. Awareness can also be improved by training the end user on how to identify risks in a standardised way (as outlined by the NFPA 70E). It can also be a visual aid to identify areas where arc flash exposure is possible.
The NFPA 70E: Electrical Safety in the Workplace has identified two areas where awareness has to be sharpened. When a person has not worked on the equipment for an extended period of time, the technician has to be retrained on the equipment. Or when the equipment has been modified a person has to be retrained. By incorporating these two areas as a standard into all training programmes, it reduces the risk of unnecessary mistakes.
Another form of awareness is visual aid. The standardisation of marking equipment with the degrees of incident energy release will assist technicians to be more aware of their surroundings. In the table below I have assigned the following colour codes for the following incident energy levels.
These colours could be used in the form of warning triangles placed directly onto the warning labels and subsequently onto the equipment. Once a technician is standing in front of the equipment and is wearing arc flash protection rated for 6.8 cal/cm2 (Orange) and the board has a red triangle marker, then he can clearly determine that he is not wearing the right clothes or he is at the wrong board.
“by creating a culture of “no barricade – no work”, technicians will start to be more safety aware when they walk into a substation”
Administrative controls involve the training, setting up of procedures and policies and determining the optimum work schedule for an individual. It aims to change the behaviour of the person rather than removing the hazard or providing PPE.
The same warning triangle that is applied under awareness is applicable here. This is an administrative control by identifying a hazard for the end user and using warning labels for the hazard.
Another effective control is to keep drawings standardised and keep them in the substation. Drawings are a key element in the safety of the workers and have to be kept up to date and in a clear defined area.
Standardisation across countries is less achievable here due to all the variables involved. However, some standardisation can occur here within companies working globally. A single company can standardise training, drawings, policies and procedures and can have a single database where this information is stored.
This is probably the most difficult area to standardise, as well as the easiest. Various manufacturers pride themselves on their proprietary technology for protecting the end user from arc flash exposure. This is good for the market and it is good for improving safety overall, causing healthy competition. I am going to focus on the easy part. Once some parts of PPE are standardised, it removes a lot of the doubt and second-guessing from the end users as to whether they are wearing the right clothing.
Since the design, function and the colours are manufacturer dependent, we can standardise on the place where warning labels or identifying labels are placed. If this is standardised – as well as the content of the identifying labels – then the incorrect clothing is less likely to be worn.
If all users know, for example, that arc flash clothing has a warning triangle on the left upper arm (indicating the cal/ cm2 rating of the suite/clothing), then it is easier to identify the correct clothing for the task at hand.
Where do we start? Any area would be a good start. If we look at training – just training your workers to be aware of the risk – most countries have a logistical challenge to get competent trainers out to remote locations. They require expert trainers, but unfortunately arc flash safety is an area that is not widely understood. Companies can achieve this by getting their resident electrical safety trainer to attend a “Train the Trainer” class and bring the knowledge and material back to their facility. If this is not possible then other alternatives exist. Companies can now buy or rent basic, intermediate, and advanced arc flash safety training videos online. DVD videos of classes can be shipped anywhere in the world, or access to online streaming classes can take place at the click of a button.
Although each country has differing legislation, some degree of detail will vary; however, the basic safety principles that prevent disabling injuries and fatalities remain constant. A good starting point for standardisation is to read the NFPA 70E: Electrical Safety in the Workplace. In the United States, this is considered a consensus standard and enforced like a statutory requirement. If your country requirements are different, consider using only those parts needed to address gaps in your current legislation or local standards. This is the approach used by Canada through CSA Z642. The standard is identical to the NFPA 70E, but country specific requirements are incorporated into the standard.
Laura Steenkamp (MEng (Electronic)) obtained her Electronic Engineering degree at the University of Pretoria in 2001. She began her career with Eskom where she developed an interest in protection engineering. In May 2008 she joined Sasol Synfuels, focussing her attention on the systems that are put in place governing and regulating protection engineering. She learnt more about arc flashes, and the way people are affected by them, during her participation in a risk analysis of all Sasol Synfuels electrical boards. Laura published a paper in 2010 about the secondary risks to a person who is involved in an arc flash. Laura joined the e-Hazard team in July 2016 and is currently the chairman of the SABS SANS 724.
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