Monday, 13 November 2017

Electricity

There are few things on this oblate spheroid we call Earth of which I am truly terrified.  On the top of my list are nuclear annihilation (which seems more likely with the recent escalation of the Kim-Trump 12-year-old child feud), earthquakes, supervolcano eruptions, and pretty much any reptile, sea life, or insect in Australia (seriously Australia, what the fuck is up with Sydney funnel-web spiders and Irukandji jellyfish?).  But a very close fifth is, as you've probably guessed from the title, electricity.

Despite excellent marks in science classes in school, I still don't fully understand electricity, nor do I really care to.  I zapped the shit out of myself trying to change out a faulty light switch back in college, and since then I try to pretend electricity doesn't really exist (not really).  Even static electricity shooting out of my fingertips every winter has me firmly believing that the world is constantly trying to electrocute me.  My relationship with electricity now solely involves me plugging things carefully into outlets and then turning those things on and off.  And as much as I enjoy fixing things, if those things involve wiring or rewiring or anything involving a fuse box, I leave it to the professionals.  Because fuck electricity.

Fortunately professional electricians exist.  I don't know if these people understand electricity completely, trust it implicitly, or just don't give a shit about the occasional zap that could potentially stop their heart from beating (which, though I am not a cardiologist I understand to be a Very Bad Thing).  Irrespective of how or why they do it, they seem more than happy to fiddle with whatever potentially lethal electrical thing has gone awry.  Unfortunately, however, not all professional electricians know what the hell they are doing.

"Electrocution" is a portmanteau of "electricity" and "execution" originally coined in the late 19th century to describe death by the electric chair.  It has since come to mean any death from electrical shock (as opposed to cardiogenic shock, hypovolemic shock, and "OMG can you believe she's wearing that to a funeral??" shock).  Electrical injuries are particularly difficult to treat because they often combine cutaneous thermal injuries (ie burns), internal thermal injuries (including muscle necrosis), cardiac electrical dysrhythmias, and mechanical trauma from the inevitable fall after the shock.  Thankfully they are also relatively rare, and most are treated at dedicated burn facilities, which mine is not.  Despite this, I still see the occasional electrical injury victim.

Like Lou (not his real name™), who was my patient, and his partner, who was not.  Don't worry, I'll explain.

Lou was driving to a job when he heard over his business radio that his partner had suffered a moderate shock while repairing an air conditioning unit in an attic space.  Wanting to make sure his buddy was ok, Lou diverted to that establishment, where he found his partner somewhat dazed but relatively unscathed.  Apparently his partner hadn't turned off the main power before starting, and at some point he had come into contact with a live wire that was hanging from the ceiling.

Now common sense would dictate either A) your partner turning off the power prior to starting, or B) turning off the power after your partner gets a nasty shock.  As you can easily tell, either way the power gets turned off.  Right?  RIGHT?

Common sense, I am sad to report, is no longer common.

Lou apparently decided to finish the job his partner had started without addressing the live wire hanging from the ceiling that had nearly finished off his partner.  He climbed the ladder to the attic space, reached down to get a tool, and as he stood up he caught the live wire with his forehead.

Hilarity did not ensue.

The shock Lou received was significantly greater than his partner's.  He was predictably thrown backwards down the ladder where various parts of his anatomy bounced off several steps, ultimately striking his head on the floor below and losing consciousness.

And that is where we pick up his story.

Lou had just started regaining consciousness when he arrived in my trauma bay.  He was clearly dazed and confused, a dark electrical burn on his forehead, dried blood matting a good portion of his hair.  Surprisingly his main complaint was his right shoulder.  A thorough workup demonstrated a fractured clavicle, a scalp laceration, a relatively severe concussion, and a small burn on his forehead (obviously).  He had no evidence of a cardiac or skeletal muscle electrical injury, but I watched him overnight just to be sure.  He felt much better, though thoroughly ashamed, the next morning when I sent him home.

I get a bit miffed when doctors in other specialties suggest how I do my job, but I admittedly get a rather severe eye twitch when non-doctors do it.  Despite this, before Lou left the hospital I felt entirely comfortable reminding him to turn off the goddamned electricity before working on it.

I also made sure to note which company he works for and made a mental note never to hire them.  Any professionals working on my power lines need to know what the hell they are doing and, you know, not die in my house.

51 comments:

  1. I learned to do minor electrical repairs like replacing a faulty switch or outlet as a Girl Scout, and learned always to switch off the power first. For more complicated work, I call an electrician, and it amazes me they seldom turn off the power first. Is it a macho thing? Do they not like having to go back and forth to the box?

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    1. there are some cases where a troubleshoot cannot be performed without the power still on.
      more often it is laziness. statistically speaking, US 120V electricity is unlikely ro result in severe injury, and as long as proper safety precautions are followed, it is easy to avoid electric shock. the other part is that while the instructions always imply that you should call the power company and have them black out the entire neighborhood, a properly installed electrical system allows the problem area to be isolated and powered down without shutting off the rest of the house.

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    2. As long as you don't complete the circuit you won't get shocked meaning you have to work on one wire at a time. Experienced electricians usually do this.

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    3. here's a bit of trivia for you: concrete is conductive.

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  2. I rather suspect they did switch off the power. The thing is, heavy appliances like an air conditioner are on their own circuit that goes nowhere else--thus making it unlikely that the live wire hanging from the ceiling was from the air conditioner.

    Much more likely was the live wire was the broken remains of a light that was on a different circuit.

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    1. or SOMETHING on a different circuit.

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    2. and in their defense, I'm sure Doc does not stop the patient's heart before he begins surgery on the patient's foot.

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  3. I know this wasn't supposed to be funny, but when I got to the part about Lou deciding to finish the job, I knew what was coming & couldn't help guffawing. I know plenty of handy types who can put up a ceiling fan for me or add a dimmer switch to a light without professional training. But I ALWAYS remind them to go to the circuit breaker & shut off the power first.

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  4. Line about Kim and Trump was sexist. You don't have to call them little girls to ridicule them.

    I understand though in Australia you have a bit laxer standards on what is appropriate.

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    1. Seriously? I have a daughter and I have a son. I've heard how little boys insult each other, and I've heard how little girls insult each other. And believe it or not, I was a little boy once.

      And I therefore absolutely stand by what I said 100%.

      Delete
    2. I don't know what it is but I prefer to go to a foreign trained doctor vs American doctors. They seem to be more caring and more open. My mother's doctor is from India. He is the best. American doctors seem to be lazy and arrogant. Thank God we found this doctor who was trained in India.

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    3. of course, you are only assuming doc is in australia, and you are only assuming he is going to go out of his way to not hurt anybody's feelings.

      Delete
    4. For once, I have to agree with our Anon' friend - you were a little hard on the 12-year old girls there doc'!

      I have one myself and she and her friends are mostly much more sensible and responsible certain nuclear heads-of-state.

      Ugi

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    5. Doc, the fact that you have a daughter is exactly why you should consider how young children internalize it when we use gender to emasculate and put down men. Comparing people to girls shouldn't be used as an insult as it cements the idea that girls are inferior.

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    6. bear in mind that Doc did not say 12 year old girls are like fatman and little boy. what he said was that their feud was comparable in nature to the sort of feud that might occur between feuding 12 year old girls. a lot of posturing and name calling and bluster, all delivered in voices that are annoying to many adults.

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    7. addendum: it should be mentioned that the dotard's voice is annoying for a different reason than a child's voice is annoying. I think we are biologically driven to find a child's screams intolerable. survival of the specias sorts of things.

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    8. Sarah - I had a feeling that phrase would touch a nerve with some people. You know by now that I choose all of my words very carefully, so if I included that phrase, there is a reason.

      I firmly believe that people these days are overly sensitive, which is why I tease my kids mercilessly. If someone flings an insult at my daughter, I want her to be able to handle it, not get upset over it.

      That said, would I be insulted if someone said something about men being overly aggressive baboons? Absolutely not. Men and women, boys and girls are different, and they quarrel differently. If you wish to see that as sexist or some kind of double standard, so be it. But know that I am raising my children to be tough and resilient and to see everyone as equals.

      Delete
    9. Had a longer comment but it was deleted, so I'll just summarize.

      The comment about not wanting your kids to be overly sensitive is half bull. It could be straight out of the mouths of the "anti-PC" Trump supporters here in the US who call social justice advocates "snowflakes," "SJWs," and "whiny." These people condone racism and sexism and are often anti-Mexican and gun lovers.

      Coming from a woman, and not a man mansplaining how his comparison of men threatening each other to girls is not sexist, your comment is definitely sexist. "Children" would have been fine, but not "girls."

      Trump and Kin arguing to me is far from a girl fight, much more like two narcissistic and powerful men ego-tripping. The impulsivity, egotism, and narcissistic anger are far more common for men, I think, rather than girls. Plus, 12 is an age when girls are more mature and more mature than boys the same age.

      A comment like that wouldn't fly in America, because we are post-aware of how wrong it would be.

      Delete
    10. How is putting down girls for their unique characteristics making them "equals?" If you acknowledge that boys and girls are different, then equality doesn't mean they are treated the same. If you acknowledge that girls are more sensitive than boys (which may itself be considered sexist), then throwing them the same insults as boys isn't treating them equally but treating them worse. You want a girl to be able to handle the same sort of teasing that a boy could, then why does it make sense to put down grown men and girls by calling them "girls," implying that "girl" means something bad? It is good to be able to handle criticism or brush off an insult. But not if the insult is "girl" with a negative connotation attached. A girl IS a girl. She cannot amend her behavior to not be a girl.

      If you do not see the error of your thinking about the sexist comment even now, I've lost respect for you.

      Delete
    11. And there is the "mansplaining" comment I was expecting. Good fucking god, this is exactly what I'm trying to prevent with my children, being overly sensitive and not being able to see a stupid joke for what it is: a stupid joke. Thanks for proving my point.

      If you want to see it as sexist, go right ahead. If you want to lose respect for me, go right ahead. If you want to stop reading or following or whatever, go right ahead. If you think I'm mansplaining, I can't stop you from thinking that. But before you go, know this: I have the utmost respect for women. I would ask you to ask anyone that knows me, but obviously you can't, so you either believe me or don't.

      I have seen the way girls argue, and I've seen the way boys argue, both when I was a child and now. The fact is that they fight differently. They are different. That doesn't mean they aren't equal, just different. I never said or implied girls are more sensitive, you said that. i did not imply being a girl was bad, you did. I was saying that girls can be catty with each other, the way Trump called Kim fat. I have literally heard girls that age tearing other girls apart behind their backs. Of course Trump and Kim are narcissistic asses, but that's not the point. Boys don't call each other fat, they hit each other. Yes, boys and girls are different. And if you don't understand or see that, that is not my problem.

      This is exactly the problem with too many people these days. You are overly sensitive, looking for an insult in everything, looking for reasons to be offended. My wife wasn't offended by the comment. My daughter wasn't either. They both thought it was funny.

      If you want to be offended and rant and rave about how sexist I am, feel free. Except that I'm not. And I don't give a fuck if you believe what I said about how I tease my kids. What I said is absolutely true. I don't want them to come home crying from school the way I did because some kid made fun of me for no reason and punched me. I want them to be able to take it in stride when they hear kids talking about them, because I couldn't. My teasing is gentle, but it teaches them an invaluable lesson: words can't hurt you. I wish I had learned that as a child, but it wasn't until much later that I did.

      And don't you fucking dare come here and compare me to racist fucking Trump supporters.

      So again, if you lost respect for me, that's up to you. But know that what I said did not come from a place of hate or disrespect in any way. You can take that at face value, or you can go. The choice is yours.

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    12. My turn, doc you found a snowflake looking for anything to pick apart that another person has to say, they aren't happy til they cram their fucking opinion down someone else's throat..

      Females are known to be more vain, when women commit suicide they cut areas that can be hidden, or overdose, it was found it's because they put more value in looks.. When women bully or try to demean another womab they use body image insults and try to tear women apart with insults about their looks.. Women are also pack mentality where men aren't..

      Soooo, if you look at it on a very basic level, Trump and Kim are trying to get their allies (pack) together and flinging insults based on each other's looks (vain)..

      I have 5 daughters and 3 sons and when my daughter's fought with their best friends they called them fat and ugly, and try to pull all their mutual friends on to their side with gossip and secrets and the fight would last 1.5 days and everyone made up and all was good, oh good lord if we tried to take their side to show a sign of support we turned in to the bad guys. But females are way tighter knit with their friends and have a tendency to have a larger social circle..
      When my sons fought with their besties it was silence and the insults about their hobbies, ie., they weren't any good at gaming, boarding, or whatever.. Males have a smaller social circle..
      I have several male co-workers under me and I tease them about being cry-baby girls, and I tell my female co-workers that they are cry-baby girls.. I tell the men at times they are too pussy to be pussies because pussies bleed, get pounded, push out life, suck it up buttercup..

      It's not offensive unless you let it be, I was called a prairie n*gger once as an insult, I about died laughing. The asshole that called me "that", decided to be the offended snowflake pissed off that I wasn't offended..

      I was told once by some shitbag on the phone at work. He said "I had no idea what I was doing because I have a pussy and people with pussies need to stay out of my line of work, my line of work is for MEN ONLY,"because I told him there was two intersections for the cross roads he was giving me, he argued there wasn't and threw the insult, and I said they are an hour away from each other. He in turn said, "he had never thought he would talk to a person with a pussy as stupid as me and my tampon must be making me deaf and stupid". I repeated what he said in front of my boss as my boss turned bright purple red told me to hang up and deny services..
      I told the asshole to call back, he refused and he told me to go to the north most xroads connection, told him nope call back with which one.. He hung up with the final words of, "Jesus Christ I hope the next fucking idiot that answers doesn't have a pussy". He called back- come to find out the xroads were the southern most, an hour away from the north most crossing.. And I made sure to let him know what the fuck I thought of his sorry ass and then passed him to the owner's son that just berated him and unleashed about me knowing the city better than the assholes common stupid ass, and how I was more knowledgeable about the streets than anyone else in the dispatch room..
      Take offense where it needs to be, taking offense to Docs off hand remark makes you a cherry-picking snowflake..

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    13. I think it was already clear from her "Texas" comments that Cali is crazy.

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    14. Smaller transgressions can often signify that larger problems are afoot. Would you rather wait for something to blow up, or address it early on?

      It is not appropriate to attack and spitefully drag down further someone who claims to be offended because you think they are not justified in feeling offended. That's true immaturity there.

      Delete
    15. My sister is Texan, you best watch yourself. I just picked up a co-workers shifts so she can fly back home to Texas to see her kids for the holiday, mind you I didn't have to.
      I am a cunt (get your facts straight) and many other things, not crazy (sometimes), and I'm not one to mince words..

      I'm not sorry your little feelings got hurt (*laughs* Anon?= just another generic person either too afraid to make a name or not smart enough too figure it out) by the Doc on HIS blog, HIS BLOG..
      Let me enlighten you a bit Anon, this is Doc's little world over here he can escape to, to post about his journeys or wetf he wants to. Let me remind you for the third time, HIS BLOG.
      At any point in time we can come or go if we like or don't like what he says (it's pretty simple- don't read the article if you're oversensitive feelers get hurt easily by leafs run over by cars).
      Doc and I didn't see keyboard to keyboard when I told him that I am one of the "Emperor Cheeto is not my president" people, we shared a heated argument and huge disagreement. I'm still of that same group- "Not my president" or king or emperor whatever chump thinks he is today.
      I mean uncommon sense isn't shared by us all (obviously by the Texas comments, I take it you're the pro-gun spouting lies for your own agenda-"thems all want 2 take mAh gunzz")
      I come here to catch up on other's opinions on (real world) issues, not to listen to someone like you that screams, "oh noes docs opinion is different than mine, I must stomp my feet like a little girl throwing a tantrum and tell you I'm going to defriend you and I hate your face, now everyone needs to take my side or your sexist or racist or gender racist or gender sexist, everyone hate doc right now because I'm mad at him because he isn't perfect like me and he says offensive stuffs about gender..

      Jesus Christ, haven't you realized by now Doc isn't PC, it's opinion pieces or medical pieces.. Take your childish ass protest else where, like- private messages, or your Facebook, or emails, or fuck off with them..

      Sorry Doc if I went over the top delete away if it's offensive. I'm tired and grouchy ass all hell, but people don't know how to mind their own business and must cram their opinions on others without having enough sense and courtesy to listen to anyone elses opinion, demand and want to be heard without hearing the opposing message..
      And the hypocritical insulting to make a point is just hypocritical and a fallacy.. I insult because I'm tired of the hypocrites..

      And Doc you gave in and changed it, still this is your world, can't make everyone happy all the time or you'll go crazy (like me) trying..

      I will keep coming back even if I don't agree with that, I still like your face, and I won't throw a hissy fit.. 😉

      P.S. did you see what I did there Doc, did ya, because I about died laughing typing it all out. And if I have to take a guess you will pull this down and I'm okay with that, I won't be offended..

      Generic Anon, I hope your day is as pleasant as you are, keep rolling keyboard warrior.. 😂 Why aren't you offended your president just cut medical coverage to how many veterans, doesn't fit your agenda- does it? Or passed a tax that will hit low income families and save him a billion on taxes?

      Sorry doc again, didn't mean to go that far off topic, I was going to say something sarcastic about medical coverage for small business owners, oh wait.... ..

      Delete
    16. Anon - I can't tell if you're responding to me or to the anon above you. Honestly it makes little difference.

      I have already made my position clear. If the offended anon above chooses to be offended, that is his or her decision. But as anyone knows who has even a modicum of knowledge about me, I will not temper my writing because it might make someone feel bad. This should be plainly obvious based on the subtitle of my blog.

      If you are offended by what I write or the way I write it, then you don't belong here. And any other people who see fit to leave a complaint about this issue will be shown the way out right behind you.

      I think I have made myself clear.

      Delete
    17. Cali - I did change it, not to "give in", but to prevent any future comments about it. I stand by what I wrote originally, but I'm just not in the mood to defend it repeatedly. I've done it once, and that should be enough.

      As for your rather humourous rant, I have no intention of taking it down. You may have gone slightly off the rails at times, but you're mostly on the mark.

      Delete
    18. And we should not be calling women cougars! Especially if they are voluptuous and in heat!

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    19. Honestly, Cali you are the one throwing a hissy fit. You are literally ranting about everything that comes into your mind.

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    20. anon: stop being a twit.

      having known lots of 12 year old girls, I agree with Doc's assessment.

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    21. Changing the text doesn't mean much. If you don't really feel it, you might as well not have changed it. Any future controversy would be deserved.

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    22. it has been explained multiple times that the original description was valid. the description has been changed to an inaccurate one, to cater to your sensibilities. if you have a further complaint, please fill out the following form and file it.

      http://cdn.pophangover.com/wp-content/uploads/butthurt.jpg

      Delete
    23. I would, in fact, would not want it changed for its own sake if the writer does not actually feel the original statement was wrong. You simplified any controversy as the simple request to change a word. Which it was not. Also, this rude defense of the blog is far more offensive than a minor, objectively sexist sentence.

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    24. Anon - I'm sure you meant to say "subjectively sexist sentence".

      I don't believe you have a say in how this blog is run. I stated why I changed it, I made my opinion clear, and you are continuing to argue. It's over. Stop.

      Delete
  5. As I learnt from my brother, who is an electrical engineer.. not only do you turn things off first, you turn them off, and then check that they are turned off.. So if you are changing a wall socket, you turn off the circuit breaker, then plug in a light to see if it's really off. Ceiling lights are easier.

    This saved me on one occasion when one of the wall sockets in my house turned out not to be on the 'wall sockets' mains ring, so it was still live after the circuit breaker was flipped. UK power is 240 volts, you don't want to mess around with that.

    All bare cables should be left that way for the minimum of time and treated as far as possible as if they were live. Just in case there is an idiot in the house who decided to switch things back on and then ask 'are you finished?'

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    1. 240 kicks. US commercial lighting is often on 277/480V power - that leaves a mark.

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  6. I have a right index finger that's missing a chunk of tissue on the lateral side and a healed 2nd finger ccourtesy of an electrocautery mishap. I was cleaning the tips of a Mallis bipolar, the patient's left leg suddenly spasmodically abducted impacting the surgeon with his foot on the Bovie pedal.

    Dumb electrical mishap, but the scent of burning flesh and latex glove was memorable. I slipped on a second glove and kept on going. The mess healed in about two weeks and I learned my lesson with electricity. Don't EVER contact the tips of a Mallis.

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  7. One time in college I was working - alone - on a shipping container-sized dehumidifier on the roof of a supermarket in Connecticut.

    I climbed up to it (it sat a few feet off the roof on some steel girders) and opened the control panel. Then I proceeded to use a screwdriver to take out the main fuses.

    They were big fuses, as it was running on 3-phase power, I think maybe 480 volts?.

    Stuck the screwdriver into the fuse holder for one leg's fuse and ZAP. Next thing I knew I was on my back on the roof. I don't know if I was knocked out and if so for how long.

    I had foolishly neglected to shut off the main power breaker. It didn't help that the design of the unit was such that when you opened the electrical access panel the big main power switch was hidden behind the access panel door. So there was no visual reminder that holy shit the big red switch is still up.

    Fortunately I had no injuries other than a slight impression of a lingering 60 hz buzz in my head.

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    1. that would most likely be 277/480. (277 to ground, 480V phase to phase) from your description of the symptoms, I'm guessing the screwdriver took the brunt of the shock, and you mainly got hit by the arc flash, which caused you to knock yourself off the equipment.

      the biggest design flaw: you should not have been able to open the cover without either turning the big red switch off, or knowing the secret interlock release to allow the cover to be opened with the switch still on.

      Delete
  8. I can’t work out why people outside of Australia are always most afraid of our spiders? I have seen more snakes than any other deadly animal we have, after that sharks and crocodiles. I had to change lanes on the freeway recently because a 3m dugite was in my lane and I didn’t want to kill it. Spiders at least are smaller than you and tend to run off if you encounter them, unless you try to take their meal, they might fight you for that. We don’t have bears or wolves, I’m way more scared of those!!!

    Still more likely to be killed by a drunk or distracted driver than anything else tho :/

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    1. bears rarely take a nap in your woodpile, and if they do, you usually notice them before you pick up the piece of wood they are napping on.

      Delete
  9. Well, when that grouchy ass spider can hide in my slipper and jab its fangs through my toenail and kill me....I tend not to like that bugger very much. It could also be that I didn’t like spiders very much in the first place so spiders that can kill me freak me out extra special...like our Brown Recluse spider. Besides, I have an aversion to all things that want to bite & kill me really, not just funnel web spiders. Even so, I think bears & wolves (& so many others) are awesome & should be protected from us!

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  10. Beware drop bears!

    The worst thing i have to fear in my garden are hedgehogs.
    I have 29 that visit during the week and man do they get loud come breeding season or when Hermione is eating or drinking and another hog dares to come in and try to eat or drink.
    She is small usually around 650g but boy can she shout. She refuses to share and will shout at any hog that tries even to the extent she gets so mad she goes backwards, and, if that doesn't work, she will charge them and try and push them away which is kind of hard when it is say a 1.6kg Herman

    For my sins, i am currently overwintering 2 fall hoglets who are too small to hibernate.
    It was 3 but Jen Jen was released tonight as he is now 780g.
    When he showed up one night back end of sept he weighed 300g and i thought he was a she as their bits were near the tail, as he grew his bots moved up to where his belly button would be ( something i didn't know hence the name)
    A couple weeks later Hamble (dad is bungle as she looks like she ran into a wall and got a flat face. A|ll his offspring look like him)she weighed 420g and then a couple days later Jemima showed up weighing 320g.
    They live in a box in my bedroom where it is quiet except they aren't they cough and shout when they spill their water and have a wet bed or the buggers learned to knock to get my attention, again usually because they either spilled their water bowl or they have eaten all the meal worms whilst leaving everything else or because one of them has the best spot under all the bedding and won't move so they are telling mom (me)

    Hamble will likely be in for another couple of weeks, Jemima is about 440g so has a ways to go and may be in all winter if we get a lot of snow or cold weather in general.
    Maybe i need to get a hutch or a few more hog houses.

    Spiders in my house4 are either eaten by my cats or given the best ride of their life in a Dyson.

    Ken Brown
    18 November 2017 at 17:55

    bears rarely take a nap in your woodpile, and if they do, you usually notice them before you pick up the piece of wood they are napping on.

    This made me laugh.
    Oooh fluffy wood that makes noises... aaaaaaaaaaaaaaaaaaaaaaaaargh

    Thanks :)

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  11. bears are also kind of stinky, I am told. sort of an unwashed bum that has been rolling in garbage sort of smell.

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  12. and yesterday I ran across do-it-yourself electrical that was so bad, I turned off the power before I worked on it.

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  13. In general, electricity is fairly benign.
    Even if the wires delivering your supply are made of pure lead (they aren't - even soldered joints in electrical distribution are pretty rare), you'll never need chelation. There will be no need to evacuate a bunch of people from their homes when some dolt with a backhoe cuts a buried line. He's unlikely to go up in smoke, and though there may be lots of spitzen sparken there is no risk of major explosion. If you leave the switch turned on with nothing plugged into the cord, it won't leak out and kill you in your sleep. It won't fill your basement when some dolt with a big giant post hole auger runs it through a main. It won't soak your clothing, requiring you to be wrapped in a fire blanket and hauled off to a decontamination shower. You will never be the victim of a drive-by shocking. You will never have your guts or precious bodily fluids splattered across the landscape because it doesn't yield at the crosswalk. Now of course those things apply primarily to artificial varieties. Natural varieties arriving from the sky can be a trifle truculent.

    And where would TV shows like ER be without their defibrillators cranked up to half a horsepower-second? Making a bunch of innocent electrons travel through a vacuum at high velocity, then slamming the poor things into a chunk of tungsten alloy is more convenient than opening a lead can of some unruly gamma emitter for making pics of pulverized patellas.

    As for bears and woodpiles, or other furniture:
    http://www.cbc.ca/news/canada/manitoba/bears-couch-lac-brochet-manitoba-1.4314743
    Parts of parks in my part of the world are frequently temporarily closed because of bears. I've never heard of one closed because electricity has wandered in to fatten up on berries.

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    1. in having a chat with one of my local power company engineers: it was their habit in the past to bury a "repair loop" in high power installations, like say, an industrial complex. some years back when they computerized their records they hired a data center to convert their hand drawn as-built records of their entire power grid to computer plots.

      so during a major remodel in one such industrial complex, they called for the location service to mark the existing power cabling, and he came out with his laptop and marked everything out.
      if you can't see where this is going, maybe you need to read more of Doc's blog: the data center hadn't thought the circles at the ends of the lines in the as-builts were significant and didn't transfer them. 10,000 volts takes the new right off an excavator. in fact, it turned it into a yard ornament. fortunately, the operator, being entirely inside it, wasn't badly hurt.

      snd our typical exclusion zone around a fallen power line is about 50 yards. especially if it is actively leaking.

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  14. Rather unsurprisingly, the consequences of Doing A Bad Job and Being Incompetent are often somewhat unpleasant. The data entry operation failed. The company that hired them failed to detect said failure, which was caused by the fact that the hiring company failed to properly explain what was required. The guy who went out to the field failed to actually use detection equipment to locate the lines. In this instance, the guy on the excavator probably was quite innocent. With the exception of the latter, I'd make a hand-to-hand daisy-chain of the lot of them, stand the last person in the chain in a grounded metal tub of salt water and hand the first in the chain a bare wire connected to that 10 kV (with respect to ground) supply. But then, I'm mean. I might let the lowly operatives stand by and watch while I processed the managers.

    "Leaking"?! You mean when a downed conductor is still fully live? I've bullied electrons for decades. I wouldn't call that leaking. Leakage current is what you get through damp and dirty insulators or the like. (Leakage current for me is usually that which flows through the nominal dielectric of a capacitor or the few picocamps that make their way across the surface of a printed circuit board that needs another pass through the washer.)

    One of the ways some people get themselves (or others) in trouble with electricity is through subscription to the nonsensical notion that current takes the path of least resistance. There is a convenient law named after Mr. Ohm that 'splains what to expect, at least with a little help from Kirchoff. The other one is that "it is the current that kills." Well, yes, but Mr. Ohm's law covers that too, though it leaves out the part about how skin through which current in moderate quantity is flowing tends to drop substantially in resistance in a relatively short time.

    On a sort-of related matter, someday I hope to hear of a lawyer, who in course of a trial for wrongful death involving a "conducted energy weapon" will actually try to and succeed in getting a rep from the manufacturer to state under oath that the fundamental purpose of their product is to disrupt the normal biological functioning of a human - and then go on to hammer home that death is a not-unpredictable consequence thereof.

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    1. and I, on the other hand, would hope the other lawyer, at that point will point out there is a reason Thomas A Swift's Electric Rifle is referred to as a LESS lethal weapon. and that the alternative IS a lethal weapon.

      and yes, the incident where they welded every bearing in the excavator was a chain reaction cockup, and the power company ended up buying the excavation contractor a new one.

      but yes, you're right that current follows all paths in inverse proportion to resistance.

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  15. I guy I knew was working on a piece of kit (I forget what now) and had the case open - no issue really since it was unplugged from the mains and he was well aware of issues like discharging capacitors etc. He came back from getting a coffee, stuck in his screwdriver and got knocked off his chair!

    Turns out his nephew of 5 or 6 years old had seen the plug dangling near the socket and plugged it back in for him while he was away! After that, he never worked on an appliance without taking the fuse out of the plug!*

    Ugi

    * In the UK we work at 240v, which kicks quite hard and each appliance has its own fuse inside the mains plug, rated approximately according to the needs of the appliance.

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    1. you also do a single relatively high amperage circuit for the general receptacle circuit, while we do multiple lower amperage circuits. I recently found out through study that your "Low voltage shaver plug" has essentially the same shock potential as our modern GFCI protected bathroom circuit. what fries our western sensibilities is that you quite cheerfully put a high performance electric flash heater on the end of the shower head.

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