Is anyone on here an insurance agent? Would it be possible to buy
insurance on Smithers and the rest of the "rebreather" list?


Bill Mee wrote:
> 
> Will,
> 
> The ouput of the ballast could stop a human heart if it was applied directly
> across the left ventricle.
> I am sure that you are aware that the current flowing in a high voltage
> system like this is miniscule and that it is not sufficent to cause much
> damage. I think you will find that the reason for placing the ballast at the
> light head had nothing to do with safety issues, but more to do with the
> issue of containg the leakage and other high voltage effects resulting from
> the lengthy cabling to the light head.
> 
> Your analogy with the bathtub, while dramatic, is not appropriate.  In the
> case of a bathtub and a hair dryer you are potentially placing a human body
> in the path of a substantial current from the hair dryer to the grounding
> system, if the tub is connected by metal pipe or concrete to a ground
> reference point. It can take as little as 20 micropamperes to place some
> hearts into fibrillation if the current flows directly through the heart,
> such as what would occur in the case of an in dwelling catheter.
> 
> The HID output voltage is effectively magnetically isolated from the source
> supply via the high voltage output pulse tranformer, located in the light
> head.  The primary circuit in the light head power oscillator is powered by
> the realtively low 12 volts from the canister.  Therefore the only current
> which may flow from a broken light head back to the source are insignificant
> leakage currents on the order of low microamperes.  When the light is being
> operated in a more conductive medium the filaments will short to each other
> if the light head is broken.  These currents are dispersed through the
> surrounding conductive medium (fresh water has a very low conductivity) and
> thus the current density through any point, such as your arm, is miniscule.
> 
> Worrying about the risks of macroshock from an HID light are right up there
> with concern about electrocution from your batttery operated CCR.
> 
> Unfortuately, you have now suggested the next new and unusual cause of death
> from a CCR along with diver error, diabetes and cardiac insufficiency.
> 
> -----Original Message-----
> From: William M. Smithers <will@tr*.co*>
> To: kirvine@sa*.ne* <kirvine@sa*.ne*>
> Cc: Kuiper, Greg <GregKuiper@pa*.co*>; 'techdiver@aquanaut.com'
> <techdiver@aquanaut.com>
> Date: Tuesday, September 28, 1999 12:58 AM
> Subject: Re: Ralph Hood - Cannister Lights
> 
> >
> >On Mon, 27 Sep 1999 kirvine@sa*.ne* wrote:
> >
> >> 7) there are no circuits or fuses in the light canister to fail ( the
> >> hid versions have a circuit in the head, but we carry replacement slugs
> >> with those)
> >>
> >
> >George, you're forgetting something (maybe you didn't know):
> >the ballast on those HID lights puts out enough voltage,
> >particularly on start-up, to stop any human being's heart
> >stone dead if you should happen to have a tube integrity
> >problem.  In fact, the reason the ballast is up at the
> >light head is that Carl Saiva realized that he didn't
> >want thousands of volts going through a wire in WATER.
> >Unfortunately, that doesn't cover you for a ballast or light
> >head flood.  What Sartek won't tell you is that you're
> >basically climbing into the bathtub with a hair dryer,
> >and hoping the cord and sandwich baggie stay dry.
> >
> >That's no shit - I love the color those HID's put out,
> >and they're very efficient, battery-wise, but it's still
> >scary stuff.  I'm speaking as an E.E. here.  Ask Bill Mee to
> >take a serious look at these things if you think I'm full
> >of shit.
> >
> >-Will
> >
> >
> >
> >
> >> 8) there are no crappy connectors in the light
> >>
> >> 9) the cord runs through the lid with a proper compression fitting, and
> >> not some plastic insanity ( like the hood) or other insecure arrangement
> >> that would allow the cord to slide and hence leak
> >>
> >> 10) the other end of the cord is equally secure
> >>
> >> 11) the slug fits exactly to the head
> >>
> >> 12) the head has exactly the correct reflector ( which is replaceable)
> >> for the perfect focus
> >>
> >> 13) the batteries plug in with no moving wires by putting the lid on in
> >> the correct oreintation
> >>
> >> 14) the pivot point is selectable for the belt loop
> >>
> >> 15) the o-rings are surface blowouts only , no embedded stupidity
> >>
> >> 16) there are other wiring issues in the head, but we will skip that for
> >> now
> >>
> >> 17) the overall lngth of even the nicad version of my lights is shorter
> >> than anything made elasewhere for the same power, and hence fits more
> >> easily along the side of the diver with no discomfort or clustery
> >>
> >> 18) only a braindead stroke would buy some has-been verion of nothing
> >> made by noboyd  when the real thing is available from the pros.
> >>
> >> 19) you are a known rookie at this, and your attraction to this light
> >> alone makes it suspect.
> >>
> >> 20) I have more, but I will let somebodly else finish this one off for
> >> real.
> >>
> >> Kuiper, Greg wrote:
> >> >
> >> > George Irvine,
> >> > By all means tell me why you think the Ralph Hood light is a pathetic
> >> > compromise for the real thing.  Also are saying that if it isn't made
> >> > by Barry Miller then it is not sufficient?  If this is not the case
> >> > then what other light brands do you recommend.
> >> >
> >> > Greg Kuiper
> >> >
> >> > -----Original Message-----
> >> > From: kirvine@sa*.ne* [mailto:kirvine@sa*.ne*]
> >> > Sent: Saturday, September 25, 1999 9:28 AM
> >> > To: Kuiper, Greg
> >> > Cc: 'Elly & Matt'; techdiver@aquanaut.com
> >> > Subject: Re: Ralph Hood - Cannister Lights
> >> >
> >> > Greg, like your Pelican backup light ( an oxymoron in this case) , the
> >> >
> >> > Hood light is a pathetic compromise for the real thing.
> >> >
> >> > Do you want to know why, or do you just want to stay in the dark.
> >> >
> >> > Let me know .
> >>
> >>
> >> --
> >> Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'.
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> >>
> >--
> >Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'.
> >Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
> >

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