If you’re already familiar with what an Arc Flash is and what type of training you might need to have in order to protect yourself from it the next thing you might be wondering is if there are any specific procedures related to Arc Flash Safety.
In this article I’ll be going over the top 2 Arc Flash Safety procedures that you need to know in order to protect yourself and your team from Arc Flash.
Let’s get to it.
Procedure 1: Establishing an electrically safe work condition
Procedure number one is a mouthful... establishing an electrically safe work condition is a really fancy way of saying “electrical lock-out” but we don’t want to get the two procedures confused, so they decided to give the electrical workers a longer more sophisticated version to work with.
This procedure really is the back-bone of all thing’s electrical safety, not just Arc Flash, but it also happens to be the most surefire way to mitigate an Arc Flash.
If there is no energy than there is no Arc Flash.
Here are the basic steps:
- Determine all possible sources of energy;
- Interrupt the load then operate the disconnect;
- Visually verify the disconnect is opened (this step is optional);
- Release any stored energy (electrical or mechanical);
- Apply lock-out device(s)
- Test for absence of voltage;
- Install temporary Protective Grounds (if applicable)
Procedure 2: Arc Flash Risk Assessment
Doing a proper Risk Assessment is going to go a long way when it comes to Arc Flash Safety. A lot of incidents can be traced back to this step being missed prior to incident.
This may be more of a thought process than a procedure, but I’ll let you be the judge of that.
Here it is:
- Identify the hazard
For this step you want to determine if you even have something that can produce an arc flash. What you’re looking for is anything that is above 240 volts, has a more than one transformer feeding it, or the transformer feeding it is larger than 125 kVA... if any of those are true you have potential.
- Estimate severity
Next, you’ll need to know how hot it can get. If you have an Arc Flash Study completed, then it’s a lot easier because you’ll know the incident energy.
1.2 cal/cm2 is the onset of a second degree burn... anything over 3 or 4 cal/cm2 and you’re going to be in rough shape.
If you just want to simplify this step... always assume severity is high.
- Estimate likelihood
For an arc flash there is two ways you can get into trouble.
The first way is by touching the wrong thing... creating an arc... and starting an Arc Flash. The second way is by interacting with the gear in a manner than it’s not supposed to be interacted with... like racking a breaker on a live bus (yes... hard to believe but go check your user manual... it won’t say rack on live bus).
- Determine protective measures
If you’ve got an arc flash, that will be too hot for your liking and your doing something that’s risky enough to get it started then put on your Arc Flash Clothing or go get a chicken switch (or some other Arc Flash mitigation technique)
So, there you have it.
Follow these two arc flash safety procedures religiously and you’ll never have to worry about being hurt!
And just for the record... you’re going to need to do procedure #2 before you ever do procedure #1... once you’ve tested (or applied grounds for HV work) then you are good to go.