Shock Protection Boundary Inquiry

[Wfg42438]

Hello Everyone,

As many of you are aware documents like NFPA 70E 2021 publish shock protection boundaries for energized equipment.

After doing some research I saw that there is more than one document out there with shock protection boundary recommendations.

Some example are listed below:

Brazil: NR-10
(

http://www.braziliannr.com/brazilia...ex-ii-of-nr10-risk-zone-and-controlled-area/)

Canada: Z462

Great Brittan : EN 501110-1:2013


Im curious if anyone out there knows if there is an Australian document or standard which also publishes its own shock protection boundaries?

 

[Sharpie8]

Not sure if this is exactly what you are asking, but AS2067 (HV Substations above 1kV) has a parameters for earthing systems step/touch voltages. It is now a probabilistic risk based approach, the older versions were firm voltage limits. It is all about ensuring safety for people within and outside the HV area considering the likelihood (probability) of a fault occurring and someone being there at the time of fault .

 

[Wfg42438]

Hello Sharpie8,

I should have clarified the shock protection boundaries im referring to is what's published in standards like NFPA 70E 2018 as shown below.

I have seen Brazil and the british standards i listed above have different values.

I was wondering if anyone out there knows if Australia has its own set of shock protection boundaries they follow and if so in what document there published.

 

[Sharpie8]

Is that for clearance from Live HV (safety clearances)? AS2067 covers that.

AS2067 is the go to for all substation stuff in Australia. AS300 covers LV ("Wiring Rules").

 

[Wfg42438]

The safe distances listed in this document mainly refer to fixed circuit parts. For example when a switchgear is being examined while energized.
So each boundary establishes locations where shock hazards exist along with instructions of what boundaries that unqualified and qualified workers can be in.

The idea is that the closer we get the likeliness of a shock hazards increase so the proper precautions are required.

I was just hoping to see if anyone out there knows if other documents like this exist for other countries such as Australia.

I see that countries like Brazil publish there own boundaries and i wanted to see if any other countries do this as well or simply follow NFPA 70e