NFPA70E Labeling

[Pvpaone]

If arc flash calculations show incident level lower that 1.2 cals at working distance what type of label should be installed? There is no longer a cat 0 and all labels say Arc Flash Hazard which is not the case. No label would not work since you would want to show that calculations have been done.

 

[mayanees]

If arc flash calculations show incident level lower that 1.2 cals at working distance what type of label should be installed? There is no longer a cat 0 and all labels say Arc Flash Hazard which is not the case. No label would not work since you would want to show that calculations have been done.

The label should report the calculated incident energy with no reference to PPE 0. A qualified person would interpret that as no PPE required.
A concept that's a little odd to comprehend is that when incident energy level is calculated, you can't include the PPE category on the label per 130.5 (C). This is because the task has not been identified, and the task is identified when using the PPE tables method.
The safest approach when using the incident energy calculation method is to present: 1) Voltage, 2) AF boundary & 3) Incident energy and working distance.

 

[steve66]

Without looking at the exact wording of the code, I'd say there is still an arc flash danger (even if its a small danger), and PPE is always required when working on energized equipment. When the arc flash energy is very low (under 1.2 cal), the PPE might only be a pair of safety glasses, but that's still PPE.

 

[Jraef]

Without looking at the exact wording of the code, I'd say there is still an arc flash danger (even if its a small danger), and PPE is always required when working on energized equipment. When the arc flash energy is very low (under 1.2 cal), the PPE might only be a pair of safety glasses, but that's still PPE.

That's how I see it too. In a seminar I attended, the presenter said that the reason there is no "PPE-0" any longer is simply because what they meant was "PPE LEVEL 0" meaning the LOWEST form of PPE, but people were interpreting it as "zero PPE" meaning they did NOT need any PPE, which was NOT the case. So they did away with that category and started at PPE-1 as the lowest level.