by Francis Pereira
After the two recent electrocutions, it’s time to take a serious look at the electrical code and electrical practices in St. Vincent and the Grenadines, particularly as it relates to grounding and bonding. We owe it to the families who have suffered these tragic losses. Electrical safety is serious business and you don’t have to be an expert in the business to know that. Many of us have had our run-ins with electricity and come away unscathed but not everyone is so fortunate. Looking at our practices in St. Vincent, it is amazing that this doesn’t happen more often.
Sometime around the late 80s, VINLEC introduced a new metering standard using metallic meter bases. Every electrical code around the world recommends in some form or fashion that “any metal part that could potentially become live should be grounded”. This new VINLEC standard did just that; the metal meter base, the building metal distribution panel enclosure were bonded to the neutral wire which was grounded at the service entrance. Soon after that, there were fires that destroyed two wooden buildings and the electrical inspectorate at that time came to the incorrect conclusion that this new standard was to blame. I say so because meters still catch fire but most people have concrete structures now so a total destruction is unlikely.
VINLEC offered a poor defence of its new standard and in the end, the electrical inspectorate got its way and the bonding to the meter pan and neutral were eliminated. As a result, every single meter base in St. Vincent is “floating” in electrical terms. The problem is, if the insulation fails inside the meter base and it becomes live, guess what? Nothing happens because that bond to the neutral was eliminated so there is no current flowing back to the utility transformer to activate a fuse or circuit breaker. Someone then comes by and touches that live base and they get a serious shock because all of the current flows through their body back to the transformer. The late Theo Wilson, former VINLEC employee had such an experience that he told me about.
I am not saying that this contributed to his eventual demise but unseen internal damage can result. A similar thing can happen with power tools and appliances in a building. In the case of a power saw with a metal body, if the saw body becomes live for any reason, because the ground to neutral bond was eliminated, a little current flows to the ground rod and tries to return through the earth but not in sufficient quantity to activate a fuse or breaker. If someone is using the saw, a significant portion of the current can flow through their body to ground depending on what they are wearing and where they are standing. The unfortunate reality is to operate a power saw you grab it with your fingers bent. When sufficient current flows through the body the muscles contract involuntarily so for someone holding a live power saw their fingers grab the saw tighter and tighter never letting go. If this persists long enough, the result can be fatal. A ground to neutral bond could have been a lifesaver. Again I am not saying that this was the case with the individual in Biabou as I don’t know the details, but these are real possibilities.
The following figures should shed some light (a milliamp is 1/1000 a unit of electric current)
40000 milliamps -to instantly trip a 20amp breaker
455 milliamps — light a 100watt bulb
200 milliamps — cause the heart lose its rhythm (fibrillation)
75 milliamps — stop breathing
40 milliamps — cause muscles to contract
Conclusion: It doesn’t take a lot of current to cause injury or death
This is reason for great concern and I hope this article comes to the attention of someone who can make a change; whether in the Ministry of Works, the Electrical Inspector’s office, an electrical engineer or electrician.
Please treat this issue with the urgency it deserves.
The views expressed herein are those of the writer and do not necessarily represent the opinions or editorial position of iWitness News. Opinion pieces can be submitted to [email protected]
The views expressed herein are those of the writer and do not necessarily represent the opinions or editorial position of iWitness News. Opinion pieces can be submitted to [email protected].