He wasn't harmed, but wood DOES conduct. Humidity changes the game. Static is low under humid conditions but is high under dry conditions.

He wasn't harmed because the roof is non-conductive.

In the US, OSHA requires that all ladders used in most commercial environments must be either wood or fiberglass. An aluminum ladder is a definite NO-NO - especially where overhead high voltage feeder lines are present.

When I went to college, a group of fraternity numb-nuts were building their homecoming float using a metal scaffold. They finished their float on early Friday morning before the game (on Saturday) and eight of them were moving the scaffolding away when they contacted another HV feeder lines. Three of them were knocked away from the scaffold, but the other five were electrocuted (and burned to a crisp). They were all on grass.

 

 

Is Concrete Conductive OR Insulative? Internet says both

It's down to the presence/absence of dissolved electrolytes --- Succinctly: dry , clean, concrete is a poor electrical conductor - albeit said 'property' is not to be relied upon from a safety (Spec. shock hazard) standpoint!

Best regards
HP

 

@panic mode -- Being, as I am, familiar with that video -- I'm bound to say - sad as it is to watch - It stands as an invaluable lesson for it's 'visceral-level' acquaintance of 'unindoctrinated' readers with the very real, clear and present nature of electrical hazards! Sincere congratulations on your decision to link it! -- I remind any dissenters - if it saves lives - it's not in bad taste!

Most sincerely
HP

 

He wasn't harmed because the roof is non-conductive.

Was the roof/wood absolutely non-conductive he would have received no shock whatever - inasmuch as no circuit would have been established! -- Again, there's a veritable gulf intervening 'practical insulator' and 'safety insulator'...

With constructive intent
HP

 

He was on shingles which is probably even better insulator.

 

He was on shingles which is probably even better insulator.

It appears his right hand may have been in contact with a tree at the time of the shock? -- Either way he was the recipient of an undeserved miracle (To wit: a relatively painless lesson in the ways of common sense)...

Best regards
HP

 

@panic mode -- Being, as I am, familiar with that video -- I'm bound to say - sad as it is to watch - It stands as an invaluable lesson for it's 'visceral-level' acquaintance of 'unindoctrinated' readers with the very real, clear and present nature of electrical hazards! Sincere congratulations on your decision to link it! -- I remind any dissenters - if it saves lives - it's not in bad taste!

Most sincerely
HP

yep, this i very sad thing to see but those poor guys would likely be alive if they saw video like this.

 

Was the roof/wood absolutely non-conductive he would have received no shock whatever - inasmuch as no circuit would have been established! -- Again, there's a veritable gulf intervening 'practical insulator' and 'safety insulator'...

With constructive intent
HP

He would have felt himself get charged, as a capacitor. Luckily, he was brought up to the potential of the power line and current gradually stopped flowing. In the following seconds, his shoes or other conducted enough to discharge hime slowly - he would have felt a similar shock as he discharged if he was suddenly grounded.

 

He wasn't harmed because the roof is non-conductive.

I have a metal roof.

He was on shingles which is probably even better insulator.

I didn't notice that.

[edit] OK, yes, I see it now. And trees are wood. Unless I'm unaware of some scientists attempt at making synthetic trees that grow.

 

I've seen that one several times and used it for a "shocker" training course. Nobody complained but everyone commented that it was an instant attention grabber. Then, I quoted this classic and got all kinds of crap and claims I want too far. Weird.

 

He would have felt himself get charged, as a capacitor. Luckily, he was brought up to the potential of the power line and current gradually stopped flowing. In the following seconds, his shoes or other conducted enough to discharge hime slowly - he would have felt a similar shock as he discharged if he was suddenly grounded.

I dunno... Granting a worst case scenario (i.e. that the contacted line is part of a 'low voltage' primary feeder network [EMF=7.2kv]): At a frequency of 60Hz fully 370pF is required to sustain the 'generally accepted' minimal threshold of perception (1mA) - moreover the victim's reaction is suggestive of a shock current in excess of 10mA --- In any event 370pF seems a bit high for an 'accidental capacitor'?

Granted! Initial contact and ensuant 'bounce' will occasion steep{er} transition times and, hence, significantly reduced instantaneous capacative reactance... -- Even so, my experience with 'high voltage' has demonstrated that isolated contact with conductors carrying up to 10kV (ELF or DC) occasions little to no sensation -- EMFs beyond 10kV, however, prove increasingly uncomfortable owing to corona effects. -- As a point of interest, it is for said reason that birds may commonly be seen resting upon primary networks but very infrequently upon shipping lines...

With unintended pedantry
HP

 

Then, I quoted this classic and got all kinds of crap and claims I want too far. Weird.
View attachment 111774

I expect some politically "correct" yob took it as 'marginalizing the handicapped' --- Wadda world!

Best regards
HP

 

I expect some politically "correct" yob took it as 'marginalizing the handicapped' --- Wadda world!

Best regards
HP

HP as member of younger generation so deeper in political dreck I'm saying it's not marginalizing at all! It's _victim blaming_ cuz it's too unfair to blame ppl for consequences of their own stupidity and negligence!

 

I thought the issue we were discussing was whether concrete is conductive or not. Where's this thread going?

Oh, and in the video it LOOKS to me like the concrete was wet.

 

I thought the issue we were discussing was whether concrete is conductive or not. Where's this thread going?

My apologies! -- Seems a job keeping politics out of anything these days

Oh, and in the video it LOOKS to me like the concrete was wet.

Depending upon the line 'voltage' it mightn't have made much difference -- Upwards of a few kV even dry concrete pavement is just 'ground'...

Best regards
HP

 

Upwards of a few kV even dry concrete pavement is just 'ground'...

Less than that, HP! I can get nasty shocks with antique upright Vac on dry portland cellar floor wearing shoes!

 

@Aelph(0)

Remember some sayings:

You can't fix stupid
You can't make stuff idiot proof. You can always find a better idiot.

An education does seem to make one less of an idiot.

I started to slowly slide down a A frame shingled roof. Knowing a little about friction, I just layed down and stopped. I increased friction. Back-up plan was to catch feet on gutter.