Switchgear Transformers

someone somewhere
Member - 13 posts

I presume you mean working or even living in the vicinty of HV equipment.

HV transmisssion lines (pylons) have been linked to various cancers but the link couldn't be proven.
Again the link came about as a result of statistics.
They were called 'cancer clusters'

Craig Stuart
Member - 37 posts

Thanks for your help. I'll check this out.

Carl Manning
Member - 7 posts

Craig your question isn't very clear; are you after specific hazards in your work place or just after general information ref HV?

Marion Jeffels
Member - 10 posts

There has been a legal case within the last two years where a school in Fullwood Winchester was able to stop a telephone company erecting a mast at a near by petrol garage as it was proven to be hazardous.

A primary school and houses in Abbey Meads N Swindon is built within the shadow of pylons. Perhaps Swindon BC would have specific environmental survey data to answer your question Craig.

Marion Jeffels

Graham Kenyon
Member - 26 posts

There are potentially lots of hazards working near, around and with HV switchgear and transformers.

But this depends on:

1. How close.

2. What type of HV switchgear and transformers and where the conductors are fed from.

3. The work activity itself. (e.g. if only near the HV equipment, what's the risk of touching overhead lines, things falling onto the HV equipment, getting too close so that open conductors can arc to your employees or work equipment, etc.)


For example, working withing a HV substation switchgear room, you'd normally provide flame retardant clothing (in case, for example, the switchgear blows an arc if it operates when you are near it), specific training, and consideration of other electromagnetic effects on your tools, test equipment, etc. Also, would consider provision of non-conducting ladders, tape measures, etc.


Do you have a specific problem or activity you'd like to discuss ?

Charlie Peel
Member - 38 posts

Craig, Graham
I am worried by what I am reading.

To me, work in close proximity to HV switchgear means that you are able to touch the switchgear.

Work this close to HV switchgear would most likely need to be controlled by a permit to work or at least a limitation of access. Both of these will give details of what can be done around the switchgear. Indeed I can't think of a time when I have let anyone work within close proximity to my HV switchgear without at least a limitation of access (including painting the walls of the enclosure)

You need to contact the owners of the switchgear, or the authorising authority, or the site authorised (senior authorised) person for further details on how to proceed.

Just remember that HV (High Voltage) is very friendly – LV (Low Voltage) you have to touch to get a shock, whereas HV will reach out and shake hands with you. To this end work should NEVER EVER be sanctioned when a person is close enough to live conductors to have HV arc to them or their work equipment.

I speak with the experience of being a senior authorised person (HV) for more years than I care to remember.

If you are worried about the health risk of working within a close proximity of HV switchgear there are plenty of theories but little if anything has ever been proven.

Graham Kenyon
Member - 26 posts

QUOTE: "To me, work in close proximity to HV switchgear means that you are able to touch the switchgear. "

That's what I'm trying to establish from Craig - and yes, the company I work for does sometimes have to send IT and Control engineers into switchgear rooms or transformer/substation pens. (As you point out, we have training, permits and additional PPE from the operator's SAPs.)

But if "close proximity" means working close to the fence around a small sub on a housing estate, for example, then the risks of tall equipment falling, work at height (and again falling, even if no overheads) and excavation are very real.

All this work requires special consideration.

Kevin Towler
Member - 3 posts

I work in the Sub-Station environment, before they can enter a Sub-Station they must have passed a "Persons and BESC" course which covers safe working distances from the conductor also issues like long objects and vehicles in the Sub Station environment.
They will need to sign onto the permit which will require them to have read the method statement and risk assessment, which would have been approved by the Senior Authorised Person especially as they are working so close to a conductor.
There should also be present on the site a "Competent Person" to supervise the work. To become a "Competent Person" you have to be signed onto a permit for 10 working days and have completed a "Competent Persons" course.

Craig Stuart
Member - 37 posts

Hi all
Sorry I haven't posted back until now - I've been moving house.

Thanks for all your really useful advice and pointers. I'm unsure about the exact details of the case as I was asked a 'general' question. Rest assured I will get back to this discussion as and when necessary!

Again, many thanks to all of you.