Power Line Safety

[Rob_LS]

Many of you have probably read the article in Professional Surveyor "Zapped by 12,000 volts"
http://www.profsurv.com/magazine/article.aspx?i=71016

There is another article on the same incident from a different perespective in the Central Coast Chapter Parallax newsletter. I think this one will give all us supervisors and managers something to think about. http://members.impulse.net/~cccclsa/par ... ec2011.pdf

Caltrans training materials on Power Line Safety are avaialble to the public at:
http://www.dot.ca.gov/hq/row/landsurvey ... index.html

Let's do what we can to be safe out there...

[Lee Hixson]

Can you give us the gist of the articles?

[land butcher]

Like the fried squirrel, touch only one line ok, touch two lines or one line and anything else, bingo we have liftoff.

[E_Page]

Can you give us the gist of the articles?

Two different perspectives, that of the electrocuted man in PS, and that of a supervisor in the office. Neither one a position anyone wants to find themselves in.

Gist of the occurrence: Rodman working in heavy tree and brush canopy on a wet day. Using a 25' fiberglas level rod as a prism pole to get the prism above the canopy.

He caught a glimpse of a wire, but thought it was a telephone wire. He apparently knew the rod was in the vicinity of a wire but unaware that he would come into contact with it.

He did and it was electric rather than comm line.

Resulted in burns and other injuries. Very disorienting. Excellent emergency response by his crew (chief was Chris Bateman who posts here from time to time IIRC) and by EMTs. Spent 1 night in hospital then went home. 3 weeks to recuperate.

Read the articles. Neal's description of being electrocuted is (pun intended but applicable) shocking. Robert Fredrick's recounting as the office bound superviser describes in the more objective terms of someone not in the thick of it, the response of the crew and the EMTs. He also discusses his response as a supervisor in using the incident to ensure that all his crews are sufficiently focused on field safety. He gives a lot of credit to the crew and their immediate response to the situation per their safety training.



It pays to be aware of all the potential hazards around you, obviously including the location and nature of overhead lines. But that also goes for the possible locations of buried lines as well.

A crew at a former employer several years ago drove a rebar through a telephone fiber optic line serving a neighborhood, cutting off phone service to several dozen homes. The line was supposed to be more than 30" deep, but the crew nailed it with an 18" rebar. That was an inconvenience for those residents and costly for the phone company (our company had no liability as the line was much shallower than code), but it could have been as dramatic as what happend to this Caltrans crew had that line been underground electric.

As to O/H wires, apparently Neal couldn't see them clearly and so may not have been able to determine whether they were insulated or not. Generally, telephone and other communication wires are encased in black plastic shielding while electric wires are generally bare and appear gray. Either way, unless you are absolutely no doubt whatsoever positive, assume that the wire is carrying some dangerous level of charge and act accordingly.

[subman]

Evan, the article I read was a 25' sectional Hixson rod. The Hixson rod I have is anodized aluminum tubing. Seems the aluminum would conduct electricity. I am not sure fiberglass would?

[Lee Hixson]

I've always wondered about a fiberglass rod. Are there any conditions where it would conduct dangerously?

[land butcher]

All phone, cable, etc companies use fiberglass ladders ONLY, they do not conduct electricity. Wood is non conductive also, not sure about carbon fiber rods.

Never ever use any form of metal near any overhead lines.

[E_Page]

I stand corrected, it was not a fiberglas rod. However, in wet conditions the electricity will conduct over the wet surface of one made of non-conductive material.

[Lee Hixson]

I stand corrected, it was not a fiberglas rod. However, in wet conditions the electricity will conduct over the wet surface of one made of non-conductive material.

Thanks, Evan. That's the type of "situation" I was thinking about, such that even a fiberglass rod can get you in trouble.

A few years ago I needed to give a contractor the height above ground of a high tension line right as it entered the substation, near the chain link enclosure fence. I was tempted to just raise a rod up to it but decided not to take any chances and just shoot it with my total station with a rod below the spot and trig up to it. Never knew if I was playing it too safe or not. Anyway, I'm still here.

[Paul Goebel]

I suppose even a fiberglass rod would be dangerous if it was wet. This is a great use for a reflectorless gun.

[RAM]

given the right conditions ANY thing will carry electric current, same as given the right conditions any thing will burn.

[Stephen Johnson]

Thanks, Evan. That's the type of "situation" I was thinking about, such that even a fiberglass rod can get you in trouble.

A few years ago I needed to give a contractor the height above ground of a high tension line right as it entered the substation, near the chain link enclosure fence. I was tempted to just raise a rod up to it but decided not to take any chances and just shoot it with my total station with a rod below the spot and trig up to it. Never knew if I was playing it too safe or not. Anyway, I'm still here.

Wood rods can carry electricity as I found out to my chagrin back in 1977.

Picture this:

Wet, humid morning. Heavy dew on everything. Me standing on railroad spur on a rail using a wood rod with metal parts.

I never touched anything, the electricity jumped. Finished the job by turning vertical angles.

That sure did tingle some.

[Dave Sigman]

I've always wondered about a fiberglass rod. Are there any conditions where it would conduct dangerously?

If it was wet as this rod most likely was it would conduct.

[BeachBum]

This experience is one I will never forget, hearing Neal scream over 4 lanes of traffic and then him tumbling down to the roadway. One major thing that helped us through this situation … the fact we have been hammered with safety and what to do in case of an emergencies, which helped us react instinctively as though one was setting a tripod over a monument.

On another note on the type of rod discussion, the OSHA investigator was a retired surveyor, and even though we could have used a fiberglass rod, or possibly found some other non-conductive material, he asked if I would trust my life with it? Simple answer, NO. Electricity is almost like water … it will find a way to travel.

I’m just glad this was a lesson we all were able to learn from, and walk away.