limits of approach

jeff_r

jeff_r

Location
BC.
for the majority of the high voltage here is 30feet. So if any part of the tree is within that, climbing or even work from the ground on the tree would be inside LOA, yes? I know regulations are different, but for BC, is there any definitive answer to this question; Can I climb in a tree if my TIP and myself are outside of the LOA of the conductor but other parts of the tree are inside? I would have to be able to run my rope to avoid a possible swing into the LOA area, and not have any material fall inside either while working. Our WCB regulations are grey to black when it comes to tree climbing it seems.
 
The way I understand it, in the US anyway, if ANY part of the tree, your body or your gear is inside the LOA you have to be qualified to work within it. The LOA for secondaries and drops is significantly closer than for primary, distribution and transmission lines.

Tom or somebody, correct me if I'm wrong on this.
 
Hey Jeff

I also live in Victoria, I tried to find info on this topic as well and was somewhat out of luck much like you. It seems that the WCB regs don’t have much if any info on this subject. I think your best bet is to talk to someone at BC Hydro they would know the regs as I don’t do much work around lines I never went farther than talking to WCB. Hope this helps
 
Here is what I have been told by people who understand the nuances of approach distances in the US.

Consider the electric line as the center of a tube. The RADIUS of the tube is the approach distance. As you're aware that changes with voltage and elevation above sealevel. If ANYTHING is within that tube the tree is off-limits unless you have the proper credentials.

There is a time when this tube can be flattened so to speak. From what I have been told OSHA considers the distance below a house service drop to be outside of a work zone. If a person starts to work in that zone they must have the proper credentials. So...if you're hiking into the backyard with a ladder on your shoulder and you walk under the service drop your access is considered incidental to being in proximity to electric lines but not working in the strictest sense.

If this weren't the case no one who is being paid to be on a property could walk under the service line. That is unreasonable.

If the housepainter, siding installer or lilac pruner start to work near the lines they are supposed to have the proper credentials.

This is my understanding for the US I have no clue about Canada, sorry...
 
Its going to have to be a big tree to have part of its structure inside the LOA and part of it outside. If it were big enough, say a 40' crown spread, there may be part of the crown outside the 30' LOA 'tube'that you can access. (or whatever the limit is for the specific voltage) As long as the wood you affect (by cutting or tieing into), or potentially affect, can't go inside the tube as a result of your work. Working underneath the primary wires makes it easier - yourself or the branches you cut can't hit the wires. I've been given the green light from hydro vegetation to work on parts of larger trees after the material inside the LOA area has been removed by CUA's.

Here there is no LOA for low voltage service wires to the house from what I understand, as long as they're not ripped out or have broken insulation you can lick them apparently.

I've talked to a WCB person about high voltage LOA and they said that if ANY part of the tree is inside, the entire tree is off limits. Period. It was hard to describe the concept of a tree growing next to high voltage being rooted next to a busy sidewalk. Can people touch the trunk? That's the aburd example, but illustrates the need to qualify.

Western Canada is behind the times - we have to use ANSI for safety regulations for climbing and pruning. There is no Canadian equivalent from what I know.
 
Hey Jeff,
As far as I understand it the limits of approach for Primary's is 10' and not the 30' you stated. And yes I think you are right that we are able to work up to, but not touching of secondary lines. Mark from Capital explained it to me one day that for primary's limits of approach included anything within that 20' tube as well as anything above, that if cut and let fall could contact the lines. I've never had it spelled out in black and white for me.
Hope that helps
Ryan
 
Only competent personnel or personnel in training under the continuous direction of competent personnel shall be assigned to perform line clearing operations within 3 meters (10 feet) of energized conductors or apparatus operating in excess of 750 volts.

That means if you, your equipment or anything you are working on can reach within 10 feet of the energized conductor then you can't work on it if you are not trained and equipped to do so.
 
[ QUOTE ]

Western Canada is behind the times - we have to use ANSI for safety regulations for climbing and pruning. There is no Canadian equivalent from what I know.

[/ QUOTE ]

I agree completely with that comment. I tried searching CSA's website to find anything that compares to the Z regs and it was pretty much a waste of time. Is there anything? If not, it would be nice to adopt similar standards though wouldn't it.

Okay here's a question...we just had a windstorm, there was a root plate failure on a small spruce and it was leaning against a powerpole that had 3 secondary (insulated house drop)wires coming off it. Would you defer to a CUA or just make your cuts and carry on Canada?

Also, it should be stressed that if any part of the tree is within LOA on a primary that the whole tree technically shouldn't be worked on. If wind picks up or you bend the branch or whatever and the vegetation makes contact with the conductor it has positive potential of being energized = ouch.

Happy Friday.
 
So in Canada is the rule with secondaries "Avoid contact" or when you say 'no LOA' that you can actually contact the wire?

In the US if you're qualified you can approach a secondary or drop under 1000v as long as you don't actually contact it.

If branches are in contact with the wire they have to be cleared with a non-conductive pole tool before working in the tree.
 
You should always avoid contact but we are permitted to handle extension cords, appliance cords etc. which are under 750 volts.
A residential service wire is normally well under 750 volts and an extension of the voltages inside the house but I wouldn't get in the habit of touching it without protection.
If you break it you'll pay for it, sometimes it's best to have the power company take it down if it's in the way.
 
10' is the first LOA distance - it goes up as the voltage goes up. There's single phase and triple phase primary lines, and one set up with 4 wires that freaks me out.
Jordan - I would take that Spruce off those service drops, but careful! And yes, wind or rain would limit the access in the big tree scenario for sure.
Sure hope Worksafe gets it together one day and spells it out for us a bit better - I think most of us know how to be safe around conductors, but we don't know how a worksafe inspector will react to different scenarios. I think they would flip if they saw someone in a tree that had a component inside the LOA.
 
I know there's a book put out by bc hydro that had colour diagrams that clearly says what's kosher and what's not for each different voltage classification. I know I keep it in my bucket truck for in field reference. I'll try and dig it out tomorrow and get the title. I picked it up when I was a groundie for Asplundh.

Jeff, I did make the cut and cleared the spruce. I was able to swing around and inspect the wires, connections, and post very well before I put chain to wood. That one was definately in the gray area. And had I not had the experience grounding for a salty CUA and seeing what one actually can get away with I just may have defered it back to BC Hydro...or Fortis I guess in this part of the province. A side note here...do you by chance work for the municipality of esquimalt?
 
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