A very troubling trend is being used by some in the electric industry. That trend is performing energized work without justification. They believe that performing energized work is defensible since they know how to protect their employee from death (notice that I did not say injury) when an incident happens. These are not NFPA 70E®, Standard for Electrical Safety in the Workplace® risk assessments. If conducted at all, some risk assessment has determined that there is a significant risk of injury from a known hazard. They just don’t want to establish an electrically safe work condition to protect the employee. The greater hazard, greater risk and infeasible criteria are ignored. They think they can guarantee that their employee will be able to return home at the end of the day. This fallacy will only serve to increase electrical injuries and fatalities.
Currently, there are only two electrical hazards, shock and arc flash, for which protection is addressed. Assume that the employer did an NFPA 70E risk assessment but decided to ignore the standard. Personal protective equipment (PPE) will be used to protect from electrical hazards. First, shock protection requires separation of the employee from exposed, energized electrical components. Insulation is the most understood of the protection techniques whether it be through air or some other insulating material. You know everything about the type of insulation and how to maintain it. You know there are several steps where human error can render this protection technique ineffective. You know the shock PPE is adequate.
The second recognized hazard is arc flash but assuming that it is a fully understood hazard can be dangerous. The only aspect of an arc flash that protection is provided for is the thermal injury. Protection from other hazards is serendipitous but you know that. You know that the real world incident energy is not absolutely known for any scheduled task. You know where the arc flash PPE came from, that it is compliant with applicable standards, what the ratings mean, that it has been properly laundered, and everything else about it. You know every step where human error with the PPE could lead to a fatality during an incident. Read my blogs regarding some of these issues; a best practice, PPE verification, and PPE as a control method. You know that the arc flash rating of the PPE is adequate for the labeled incident energy.
You know that your employee is protected from the two hazards addressed. There are additional known hazards that you must protect them from but these are not currently covered by a standard. But you know that. An arc blast is one hazard that the industry has not come to agreement on. You have seen videos of an arc flash and the blast that accompanies it. Some say there is a great increase in pressure while others dispute this. A blast in a closed enclosure generates a different pressure than that from same enclosure when it is open. The chutes, channels and shape of an enclosure can alter the pressure imparted upon the employee during an incident. Employees have been knocked down or blown back yet there is debate on what had really occurred. Covers, bolts, and other electrical parts have been found several feet away. Employees have been hit by shrapnel. And yet there is no agreement on how to determine how bad a blast will be or if it will even occur. If blunt force trauma is a potential blast injury there are no protection techniques. You know this then make an assumption that an arc blast will not happen since you are not providing protection anyway.
You don’t want to shut the equipment off even for the few minutes that many properly planned repairs take. You have not justified the need for energized work. With your employee suited up, you will make many assumptions before they begin. One is that they will follow your infallible electrical safety work program, practices and procedures to the letter because you have trained them so well that they would never deviate from it. Another is that they will properly select and use or don any PPE. Your assumption that nothing will go wrong is what causes a problem. Allow me to make an assumption of my own; you know that your employee is being put at risk solely for a monetary reason with a perceived value greater than that of the employee.
Your employee on a step ladder leans in a few extra inches to get a better view of what they are doing. There is an incident. It could be human error or finally the equipment fails. The sound level hits 160 dB. Caustic fumes are emitted. Carcinogens are present in the smoke. A trough cover is ejected from the top of the equipment. The incident lasts part of a cycle longer than used for the calculation although the circuit breaker was maintained. Once again you knew all of this would happen.
Such things have happened. But you knew that the hearing protection would prevent damage at the decibel level. You knew that the ejected cover hitting their face shield would not knock them off the ladder causing secondary injuries. You knew that their head was protected from the increased energy. You knew that your employee would close their eyes to avoid retina damage from the intense light. You knew that the fumes would not cause long term health issues because you knew that they would not gasp or inhale when the incident occurred. You knew that they would not breathe in the smoke and molten metal vapor that filled the room. You knew that they were not wearing underwear that would melt under PPE. Since you knew the exact incident energy you knew not to apply a safety factor to the PPE rating. You also knew that the PPE had a 100% success rate at that incident energy. You knew that an arc blast would not be part of this incident. You knew that the employee's constitution was high enough that this incident would not affect their ability to continue to function at their job. Never mind that the electrical equipment is severely damaged thereby defeating your reason for unjustified energized work in the first place. The outage was not unexpected because you knew it would occur. So, you knew to have high cost, one-off, spare equipment onsite that very quickly replaced the damaged equipment with no disruption that took longer than a planned repair after establishing an electrically safe work condition.
What do you know now? You know that you may have been prevented a fatality but your employee’s family knows that they did not return home today. Also, OSHA knows that your employee was injured regardless of what you thought you knew.
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Next time: Why you need to train an unqualified employee.