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holmes1880
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I know its flimsy. Blasting cap has a critical zone where the pressure is the highest. For a 300mg base charge and 200mg primary, size 6, the zone
would be 1cm; at 2cm the pressure pressure would be exponentially lower. @3cm you may not even lose the finger, but you'd get shredded/ heavy
bruising.
I wish there was some data on that, but I have failed to find it in the past.
I will redesign my pressing station soon, probably using a very thick wooden block wrapped in a bubble wrap and some gorilla tape.
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albqbrian
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Why hold it???
Why would your hand need to hold it? Surely it can't be too difficult to find some alternative that keeps your hand off the thing? I know the
chemistry part is always more interesting; but we need to give some thought to basic "fixtures" that can add a huge level of safety for very little
investment.
The old US Army manual on improvised explosives has a nice press set up. You end up pressing down on the end of a decently long stick thus placing you
well away from the stuff being pressed.
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Blasty
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Quote: Originally posted by Lord Emrone  | | holmes, your ETN-press-thing doesn't look safe. You should surround the cap with an absorbing material like styrofoam. Wood doesn't absorb. If your
fingers are in the same position as on the picture during a det, you could very well lose your thumb. And instead of aluminium you should use paper.
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Back in the days when I used to tinker with HMTD, I would surround the loaded aluminum tubes with lead ingots. When one of these tubes exploded during
pressing with a wooden dowel, most of the shock and shrapnel was effectively absorbed by the ingots. My ears were ringing for several days, though.
That was the end of my HMTD ventures. I do not trust peroxides.
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Lord Emrone
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luckily for you this happened when making the cap. I wish I had had such an experience before my accident, but my AP seems to be undetonatable without
a hammer.
OT : the topic title isn't right, there is almost no way TS would be killed, even with cut veins. It takes a lot more to get a serious chance to kill
a full-grown human being.
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Bot0nist
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While the amount of ETN that detonated may not have been enough to end aqua's life, it was more than enough to end it 'as he knows it' if he had been
holding the test tube a little higher, or a little lower. Ask any man who has lost his ability to see, or his genitals.
A severed artery, coupled with a loss of consciousness can lead to death through blood loss very quickly, and in any right, I'm sure aqua's feelings
when initiating this thread were a bit panicked. I bet he realized that had the amount in the test tube been slightly more and if he was slightly
closer a very severe injury could have resulted.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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pjig
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| Quote: Originally posted by holmes1880 | I use electrical tape, gorilla tape, and again electrical tape. It would be shocking if the wood would splinter through those layers. I'm wearing
thick goggles, just in case, so I'd be all right. Hearing would suffer, I'm sure, but in the short term.
P.S. Yes, I need to put it to the test in a thick cardboard box to see how the splinters behave and whether the wood is catching the aluminum
shrapnel.
[Edited on 12-6-2011 by holmes1880] |
I just got to say, this is very dangerous if you are holding it while pressing. A press with a blast shield is a must for your protection ... Just a
thought but test one of your blocks by firing a cap off in it and see the real test, you could place a soft item like a melon or something next to it
to simulate your hand. See if it doesnt detour you forever from holding one of these things while loading it.
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The WiZard is In
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The "Professional" "Amateur"
Recently [ca. 1983, in the FDR], an about 80-year old pensioner was
suspected in spite of his old age, to occasionally supply against
payment anarchist circles with explosives... During forensic
examination of the exhibits the interest was soon concentrating on a
yellow substance similar to picric acid which had been seized in
powdered form, but also pressed into bars....By IR- and 1 H-
HMR spectrometric methods it was possible to quickly identify this
chemical as...---.... &c.
...has found little application as an explosive in former times,
however, was during World War II to a limited extent...
Nowadays, it seems that it has almost no significance anymore.
[Edited on 13-6-2011 by The WiZard is In]
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Rosco Bodine
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| Quote: Originally posted by aquaregia | I have a wife and kid which I love ...[snip].
I do not believe in the divine and am a comfirmed atheist.
But, when you consider that the glass only hit my torso and harms instead of my eyes (I was not wearing goggles even though I normally do), it is a
miracle. [snip] Life is very beautiful for me right now, and I never appreciated life as much as I do now. Can I be any clearer?
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There is some contradiction in what things you say.
You are on a steep learning curve, but only parts of it are you getting right. Here's a bit of music to accompany you on your path to enlightenment,
which is only so much connecting the dots....where the distance permits. Where the distance is greater .....you have to make a leap of faith to reach
the next handhold or step.
http://www.youtube.com/watch?v=yeoRGIeYWiQ In The Palm Of Your Hand
http://www.youtube.com/watch?v=rdT5BK-eqVY Remind Me Dear Lord
http://www.youtube.com/watch?v=10W09CEChCg Canto Della Terra
http://www.youtube.com/watch?v=jz0QsNAUjpo Come To The Savior
http://www.youtube.com/watch?v=0ZSLwmdHExI Lead Kindly Light
http://www.youtube.com/watch?v=h9oW91Iv8D8 Are You Washed In The Blood?
http://www.youtube.com/watch?v=dNDSjrdj530 The Lord Is My Shepherd
http://www.youtube.com/watch?v=PO17DIeI7Ec The Lord Bless You And Keep You
http://www.youtube.com/watch?v=x6qE6QEqFl8 Eternal Light
http://www.youtube.com/watch?v=k5HOBFpZRUE Deep Peace
http://www.youtube.com/watch?v=3sgD2JXk4XQ How Shall I Sing That Majesty?
http://www.youtube.com/watch?v=GW93fUe_GwU Adoro Te
http://www.youtube.com/watch?v=06D2zcGFuXQ May The Road Rise Up
Get Well Soon
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holmes1880
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Edit: getting back on topic.
I think a thick wooden block and a long dowel should suffice without having to create any pressing machinery. That being said, if I was pressing a
peroxide or MF, I would consider making a press as remote as possible.
[Edited on 13-6-2011 by holmes1880]
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pjig
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Thanks for the interesting pics WIZ... That guy had quite simple yet effective setup. I still would feel much better with a blast shield between me
and the press. Were the molds used to press the other exp.'s as in booster pellets etc..? I'd imagine that the metal former with the inserts (sized
to fit the caps) served as a protective barrier between him and the cap. All very interesting to see how someone else does their dirty business .
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The WiZard is In
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| Quote: Originally posted by pjig | | Thanks for the interesting pics WIZ... That guy had quite simple yet effective setup. I still would feel much better with a blast shield between me
and the press. Were the molds used to press the other exp.'s as in booster pellets etc..? I'd imagine that the metal former with the inserts (sized
to fit the caps) served as a protective barrier between him and the cap. All very interesting to see how someone else does their dirty business . |
The press was not the subject of the paper therefore, no
details were provided.
Forensic Comparison of Explosive Samples by Proton Magnetic
Resonance Spectrometry.
djh
----
The Dance of Death
Two girl employees of an explosive factory
in Westquater were engaged in carrying
a box containing detonating caps and priming
composition for same form the magazine
into the workroom. They set the box on the
ground and began to dance together. One
of the girls stumbled and turned over the
box of explosives, which caused the
explosion of the whole load, and both
girls were blown to pieces.
J. Phillips
The Handling of Dangerous Goods, 249; 1896
In:— H Brunswig
Explosives
John Wiley & Sons
New York 1912
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holmes1880
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^ What? You'd think she'll at least act like a human shield from all those caps going off. How many caps were there for heaven's sake?
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The WiZard is In
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| Quote: Originally posted by holmes1880 | ^ What? You'd think she'll at least act like a human shield from all those caps going off. How many caps were there for heaven's sake?
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Sorry my time machine is down for maintenance.
Human shield well someone(s) witnessed the accident
and survived to tell the tale...
The Annual Report (Nineteenth) of Her Majesty's Inspectors of Explosives for 1894.
Extracted in:— The Journal of the Society of Chemical Industry. July 31, 1895.
From experiments which have been made, it has been decided to raise the
dividing line between a cap, and a detonator, the distinction, being defined as
follows ; " A percussion cap to be one containing a charge not exceeding 0.5
grain of composition, or 0.6 grain of composition where the quantity of fulminate
does not exceed one fourth of such composition; in any other case the cap will
rank as a detonator." But it is pointed out that "where the caps, are raised to a
high temperature by the aid of artificial heat, or even still more decidedly when
loose composition becomes intermixed therewith," the liability to explode en
masse " undoubtedly presents itself in a very appreciable and even a formidable
degree."—W. M.
The NY Public Library has a complete run of HM Inspectors of
Explosives reports - they are fascinating reading. However,
do to their really poor state ... printed on really cheap paper
they would will not copy them other then by photographing
big $$$$. Every-time I looked at them I said to myself ...
if anyone drops these ... they will turn to dust. There was
a set for sale some years ago, however, it was beyond my
exchequer at the time to purchase them.
I am still amazed at the difference between England and the US of
A. When there is/was an explosive accident in England it was
investigated by HM Inspectors of Explosives and published in
the annual report. In the USA accidents are investigated by the
Bureau of Alcohol Tobacco and Firearms. Their reports are
written up, shown to no one - placed in a rocket and fired into
outer space never to be seen again.
Explosion of detonator composition ; Circumstances attending an——-which
occurred at the factory of Messrs. Kynoch, Ltd., at Holford Mills, near
Birmingham, Staffs, on July 29, 1913. Major T. H. Crozier, H.M. Inspector of
Explosives. (Cd. 7090.1
Tim first explosion appears to have occurred at the priming machine, and was
probably caused by some action of the workwoman in connection with this
apparatus. It was possible, that a small quantity of fulminate composition might
have adhered to the underside of the plate, or the guides for the block, and that it
might have been fired by the action of sliding the block into position. The camel's
hair brush used for spreading the composition over the tray was a flat one with a
light wooden handle. The metal socket holding the hair was bound round
carefully with indiarubber tape, and the brush had been in use nearly a fortnight.
It was perhaps possible that a blow from the wooden handle might be sufficient
to explode a thin film of fulminate composition. The second explosion was
caused by the first, which shook down the cement lining, bringing with it a
cupboard containing a bowl of fulminate composition, and this bowl exploded on,
or near, the floor below the position of the cupboard. The inspector considers
that the explosion was entirely accidental and that no blame could be attached to
any person in connection with it. Work was proceeding in a regular manner and
the only suggestion made is that the brush employed for spreading the
composition on the tray of the priming machine should have some form of handle
other than wood. A handle either of buff leather or indiarubber would be
preferable-C. W. McD.
79--What other Accidents than those caused by Frozen Material may occur in handling
Explosives.
Another kind of accident in handling is reported in the 1905 Report of H.M. Inspectors
of Explosives, from which many of the examples following are also taken. A contractor,
having prepared the charge and fixed the detonator, is said to have attempted to make
a water-tight joint with the fuse by cutting off a piece of the explosive (Blasting Gelatine)
and applying a lighted match to melt it. When the cartridge caught fire the deceased
attempted to extinguish it by grasping it in his hand, whereupon it exploded.
Fifty-seven accidents are reported to have been caused during 1905 by explosives
being ignited by a naked flame or spark in the course of blasting operations, and in
every case but two gunpowder was the explosive involved.
Three persons were killed and 63 injured by these accidents, which were, in many
cases, due to nonconformity with the usual regulation enjoining the removal of the
candle or lamp from the cap before preparing a charge. Numerous accidents also occur
in connection with the insertion of a detonator in a charge, and also in the practice of "
socketing," which consists in the use of small charges for enlarging the end of a
borehole, to enable a powder charge to be concentrated at the back of the hole.
Others have arisen owing to want of knowledge as to the extremely sensitive nature
and violent properties of fulminate of mercury, which is the essential component of a
detonator.
There is an instance recorded of an official shot-firer in a mine who withdrew the electric
fuse from a detonator cap and then proceeded to extract "the stuff in the end of the
tube " by the aid of a pin. The " stuff " of course exploded, and the official lost one eye
and three fingers.
Another accident occurred in the following manner at a colliery where electric shot-firing
had recently been introduced : A number of underground officials were together in their
"cabin," engaged in writing their reports. One of them was testing electric detonators
through a dry cell and galvanometer circuit. The latter instrument had three terminals,
one common, the other two attached respectively to low and high resistance coils. A
certain " cap," just tested, gave no deflection on the galvanometer needle, and was
therefore inferred to, be a bad one. An onlooker essayed to repeat the test, and,
assuming that the detonator really was faulty, applied, as he thought, the same test as
before. Unfortunately for him he completed the circuit through the low instead of the
highresistance galvanometer coils and the detonator " went off." The man lost two
fingers. Another operator tested a detonator through a low-resistance galvanometer,
and, cautious in his. way, used a dry cell supposed to be almost exhausted.
He, too, neglected the important precaution of placing the detonator in an iron tube or
otherwise out of barm's way before testing, and, as its " bridge " chanced to be
somewhat weaker than usual, it exploded, and a piece of the copper capsuler became
embedded in his eye.
Eleven accidents of this character occurred in 1905. In three of there cases it seems
probable that the injured person & were fully aware of the dangerous nature of the
article, and bad only their own folly to blame for their injuries.
In two cases there is no reason 'to persons bad any idea of the danger the cases it may
be assumed, from the fact t that the injured person was aware that they was probably
unaware that they were dangeroously so.
WM Maurice
The Shot-Firer's Guide: A Practical Manual on Blasting and the Prevention of Blasting
Accidents.
"The Electrician" Publishing Co. London nd ca 1910
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holmes1880
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SMH @ the electric cap testing. So they were testing if the circuit is complete and whether the bridge wire has not separated. Without having a
detonator covered by a sandbag, this is so absurdly reckless. I use 20 AWG wire in my electric setups for safety, and MF isn't my choice of primary.
With that being said, I also believe they were holding the cap by the explosive section, and that's what takes the fingers. Holding a cap by the
insulating header vs. where the primary and the base charge is...so 1-2 cm, could mean a difference between bruising or vaporization of tissue and
bone. In my caps, the insulating header is 4cm long, and that's how I prefer to handle it or leg wires.
[Edited on 14-6-2011 by holmes1880]
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Rosco Bodine
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@aquaregia Hope you are feeling better. Of course it is fortunate that the entire sample did not go, as the part which did not go may have had your
number on it.
You really should count your lucky stars, or however it is you give thanks. In chemistry of course, temperature matters. If temperature matters in
the temporal then it may also matter in the eternal .....just a thought.
http://www.youtube.com/watch?v=3UYfa0jeL4k Mystico
http://www.youtube.com/watch?v=_jQkT5dsupQ
a bit more piano
Keep in mind all those things for which fingers may be good to keep on hand.
http://www.youtube.com/watch?v=PaMkj4_H8WM For The Beauty Of The Earth
http://www.youtube.com/watch?v=WlhV80QPUuI All Things Bright and Beautiful
http://www.youtube.com/watch?v=xLxM0s6XOJo Look At The World
http://www.youtube.com/watch?v=GzTbo1XQfvE In Michael's Realm
[Edited on 17-6-2011 by Rosco Bodine]
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freedompyro
holmes1880
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This guys accident was his own fault. You should never "burn" your equipment clean... Ethanol, methanol, and acetone are your friends...
Holmes I think I might be the person you were referring to on youtube earlier in this thread. This name ring a bell?
I no longer have any interest in ETN, however... I would like to note that I never had any problems with pure ETN. I do remember that most times in
order to get a purity high enough for detailed use it would require a double recrystallization... Sometimes even then only the top half of the
crystals had enough clarity to be considered for use.
I later changed my synthesis so that I was able to obtain a stable acid free product without recrystallization. If I remember correctly it required
reducing the E to a powder less than 500 mesh before nitration that could be sufficiently deacidified without recrystallization... Once deacidified it
was then suspended in a sodium bicarbonate/water solution and heated to melting and precipitated to the bottom and then allowed to cool into a solid
cast. This was done via a double boiler. Never did long term storage stability tests though...
The sensitivity of ETN seemed pretty low to impact from all the tests I did. I once attempted to hammer 50mg enclosed in Al foil on a granite counter
but couldn't get it to do anything so I proceeded to use a torch on it and knocked out my hearing for 10 minutes...
With heat and confinement it gets unstable easily... I was able to reliability DDT it with American Visco fuse with heavy confinement. Chinese fuse
types wouldn't work.
I have never had an accident in pyrotechnics or HE. Nowadays I consider the primary/rocket/tube method to be the only truly 99.999999999% safe way to
DDT a substance... Odd how much safer I am nowadays even though I never had any accidents.
[Edited on 17-6-2011 by freedompyro]
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quicksilver
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A good quality sample of ETN has a very high sensitivity to impact; it was the granite that altered the example (IMO). Steel on steel would be more
appropriate & there you'd see something remarkably close to MHN.
Realistically there are several issues that could have altered testing results but a dissimilar hardened surface is often problematic for impact
testing.
[Edited on 17-6-2011 by quicksilver]
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holmes1880
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Not sure freedom, I think it maybe another guys who uses the candle. Maybe your imposter?
For any ETN use, you have to recrystallize at least 1 time. It also helps tremendously if you work with small quantities- under 10grams.
That's very true, silver, that pure product is damn sensitive to impact. Usually first hit steel on steel sticks ETN to the hammer or compresses it on
the surface, and the 2nd hit sets it off every time. 30cm hammer drop usually suffices.
With all that said, ETN is safer than LA, SA, DDNP, or any peroxide by a wide margin. It will never go off from static or normal friction, nor
pressing. MHN, on the other hand, has been reported to do some of those things.....it is quite a bit more sensitive, although still safer than any
primary.
What is "primary/rocket/tube"?
[Edited on 17-6-2011 by holmes1880]
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the Z man
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Ok I see now it is the time of technical discussion and this post may be a little bit off topic, but I really want to say something before leaving.
Obviously I want to say to aquaregia that he has all my respect for having shared his experience and I'm glad he's pretty fine. Then I would like to
thank everyone who made me understand how really dangerous this kind of experiments are. You know when you start it's all fun and jokes and it is very
easy to have the "it will never happen to me" attitude. Sometimes only strong words make you understand better, especially when you are kind of fool
and/or you are young (like me actually ) I remember a topic on azides where IIRC
quicksilver and someone else wrote really harsh posts to anyone who was thinking about using azides without understanding the real dangers, that was a
lot of people actually, me included  . After that topic I started thinking that
maybe I had to have a break and think if I really wanted to go on. Then, in this months, I realized that now I have many other things that keep my
mind occupied. I am not sure now I have the needed concentration for not committing any error. And when you're messing with dangerous reagents and
especially HEs every single error can lead to really serious consequences for yourself and others. My best wishes for everyone, have fun and stay
safe. Good luck 
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holmes1880
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HE accidents are tied directly to experimenter's IQ. There are people on here who've worked and tested energetics for decades and never had an
accident. Why? Because they are intelligent and they make intelligent choices.
I don't buy this "everyone makes mistakes" excuse. The real issue is *what kind* and *how many* mistakes you make. When people have an accident they
tend to meet several conditions that adds up to a bad result. If you think of any known accident, there is more than 1 mistake that is made and the
person having an accident knew that they were taking a big risk.
There is a reason people like silver or Bodine never had an accident. See my first sentence.
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freedompyro
holmes1880
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Make/cut a tube, make a rocket that just fits inside. Glue (Nitrocellulose lacquer works) a small amount of primary at the tip of the black powder
rocket compressed and encased in very thin plastic/al foil. For more heat at the tip of the rocket you can fill in around the primary with a high heat
composition... Eg, silicone metal black powder.
Fuse and fire the rocket into the charge via the tube. If the primary goes off from static or something random pre set-up it's no problem. :/ Very
similar to a drop cap but it can be placed at any angle... Like sideways which is required for getting rid of dead trees...
[Edited on 17-6-2011 by freedompyro]
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The WiZard is In
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| Quote: Originally posted by holmes1880 |
I don't buy this "everyone makes mistakes" excuse. The real issue is *what kind* and *how many* mistakes you make. When people have an accident they
tend to meet several conditions that adds up to a bad result. If you think of any known accident, there is more than 1 mistake that is made and the
person having an accident knew that they were taking a big risk. |
If you think of any known accident, there is more than 1
mistake that is made and the person having an accident knew that they were taking a big risk.
Well .... yes.
Hudson Maxim
Dynamite Stories
1916
DISCHARGING PAT
A WORKS foreman of mine had been employed as assistant
superintendent in another dynamite factory told me the following
story:
He one day intercepted an Irish laborer who was taking a barrel,
which had been used for settling nitroglycerin, down to the soda
house, with the intention of filling it with hot nitrate of soda from the
drying-pans. The foreman scolded Pat roundly, and told him that,
should he do such a reckless thing again, he would be instantly
discharged. The foreman then went to the superintendent's office
and reported the matter.
In the meantime, Patrick, utterly ignoring the injunction, simply
waited for the foreman to disappear, then proceeded to the drying
house with the barrel and began to fill it with the hot nitrate of soda.
Over in the superintendent's office the foreman had just completed
his narration of Pat's carelessness, when there was a thunderous
report and a crash of glass, and Pat's booted foot landed on the
office floor between them.
The superintendent dryly remarked, "Evidently, Pat is already
discharged!"
And no.
(c) Accidents when Firing.—Accidents have frequently happened. where men, either from ignorance
of the fact that a shot was being fired or from want of judgment, exposed themselves to the flying
d6bris. Rigid adherence to a suitable code of rules should be the means adopted for the prevention
of this ,class of casualty.
Following are records of a number of accidents belonging to this class:
1. Through not taking Proper Cover.—At a mine in Durham deceased fired a shot by electricity when
standing 23 yards from the shot-hole in the direct line of fire. He was struck by a stone. A small
refuge hole was available close by.
A shot-firer was struck by débris from a shot in a Derbyshire mine through using so short a cable that
he could not take proper cover. A minimum length of cable is now specified in the Explosives in Coal
Mines Order (see 2 (e), p. 173).
Some eight years ago an accident of an almost incredible nature happened in a north country
colliery, and is instanced as evidence of the necessity for extreme caution in those engaged in
shot-firing. In Fig. 70 [alt.art.pyrotechnics fig. 70] will be seen a plan and sections through a heading
or tunnel driven in the rock. Two men, father and son, having connected the line wire with a charge,
in the head end, placed themselves for safety behind the second ventilation door as shown. The
young man, standing with his back to the door, fired the shot and, according to the father's statement,
the door opened at the moment he heard the sound of the explosion and his son rolled over dead.
2. Through neglect or omission to see that all Persons are in sale positions before completing the
Firing Circuit.—Two men were recently killed at different Durham collieries. Each was connecting the
cable to the detonator leads, when the shot-firer, thinking the man had taken cover, exploded the
charge.
At a colliery in Northumberland a shot missed fire, and on testing the cable it was found to be
defective. The shot-firer cut off a portion of the cable and sent the hewer to short-circuit the further
end of the cable (for the purpose of a re-test). Through some misunderstanding, the latter connected
it up with the detonator leads, and on the shot-firer attempting to make the test the charge exploded,
killing the hewer.
At a Durham colliery, whilst the shot-firer was connecting up the leads, the hewer by mistake turned
on the current, causing the shot to explode.
At a Staffordshire mine a shot was fired while the cable was being attached, through the use of the
battery for testing cable at the same time. One man was killed and another injured.
A shot-firer left the cable from a missed shot attached to his low-tension battery. On coupling the shot
wires to the cable the charge exploded and he was killed.
Another accident, the cause of which will strike the reader as being particularly stupid, occurred in a
midland colliery.
A shot-firer, having made the connection between the wires connected to the charge and his line,
requested another workman to hold the wires apart at the joints, so that in paying off cable no
short-circuit would be produced through an inadvertent pull. Having paid out sufficient length to place
himself in a safe position, he immediately fired the shot, forgetful of the fact that his comrade was
holding the wires at the shot-hole. It is difficult to say which of the two men most deserved the
inevitable punishment.
3. Through contact with Electric Signal Wires.-An unexpected fatality occurred some years ago in a
stone drift branching at right angles off a main haulage road. In the head end, distant, perhaps, 80 or
100 ft., a shot-firer joined the fuse wires to his firing line, and proceeded to pay out the latter towards
the main road at the same time that the workmen were engaged in removing their tools from the
working face. On the arrival of the official at the junction of the roads the portion of firing line
remaining uncoiled was passed over a set of bare iron electric signal wires. In this act either the two
'free ends of the cable or possibly a bare end of one and an uninsulated place in the other in some
way completed the circuit through the signalling battery, and as a consequence the charge, ex-
ploded, causing the death of one of the workmen remaining in the vicinity of the shot.
Another accident, the cause of which was traced to the use of signalling wires, occurred at the
Worsley Mesnes Colliery, with fatal results to two workmen. The circumstances (vide Report of the
Inspector of Mines for the Liverpool District, 1904) were extraordinary.
It appeared that three drill holes were prepared at the face of a steep tunnel, and one of the
deceased, who was the appointed shot-firer, came there, bringing his firing battery with him. This he
left at the top of the tunnel, and going down, proceeded to charge and stem the three holes, and
having completed this work he was heard to say " Which shall I fire first ? " Immediately afterwards
there was a violent explosion. The evidence given at the inquest made it clear that the shot-lighter
used the signalling wires to fire the shot, forgetting, or not appreciating the fact that the wires were
attached to or in circuit with an eight-cell battery.
An eight-cell battery (say, 8 or 9 volts) is not normally strong enough to fire a detonator such as was
used here, but when a bell is in the circuit and this is rung, there is an induced, or, as it is called in
the Report, an " extra breaking " current for an instant giving. a spark, as is the case in switching off a
motor.
By experimenting with dummy detonators (i.e., electric fuses), Mr. Hall found that it was quite easy to
fire the shot by this means ; all that was necessary was that the wires should touch each other after
being attached to the shot, then instantly the bell rang and the shot went off. In this accident there
was a breach of Special Rules in that the deceased shot-lighter did not have his firing battery with
him whilst coupling up to the charge.
A third fatality arising out of the use of signal wires for shot-firing occurred at a colliery near
Wakefield so recently as April, 1908. Experience cannot teach if men wont learn.
4. Through misunderstandings between Workmen.—At least 20 serious accidents have arisen
through misunderstanding between a shot-firer and a fellow workmen. A charge for some reason
misses fire. One man goes to seek the cause of failure whilst the other waits by the machine. Some
signals will be exchanged and misunderstood and the operator starts to work his machine. The shot
unexpectedly goes off and an accident is the result. (See also 2, p. 120.)
Wm Maurice
The Shot-Firer's Guide: A Practical Manual on Blasting
and the Prevention of Blasting Accidents.
"The Electrician" Publishing Co. London nd ca 1910
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bbartlog
International Hazard
Posts: 1139
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Location: Unmoored in time
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| Quote: | | HE accidents are tied directly to experimenter's IQ. There are people on here who've worked and tested energetics for decades and never had an
accident. Why? Because they are intelligent and they make intelligent choices. |
You put too much weight on IQ and too little on personality traits - notably conscientiousness (which is just as valid a psychometric measure as IQ)
but also simple willingness to take risks. Actually, now that I think about it, the main risk factor for HE accidents seems to be possession of a Y
chromosome, despite the fact that this doesn't lower IQ in the slightest :-).
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The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
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| Quote: Originally posted by bbartlog |
You put too much weight on IQ and too little on personality traits - notably conscientiousness (which is just as valid a psychometric measure as IQ)
but also simple willingness to take risks. Actually, now that I think about it, the main risk factor for HE accidents seems to be possession of a Y
chromosome, despite the fact that this doesn't lower IQ in the slightest :-).
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Yes. Safety is a frame of mind, and a disciplined way
of working.
Statistically the highest number of injuries from misadventure
are to adolescent males.
Tap-TAP-By-BY
Extracted from:—
Metal and Nonmetal Mine Safety and Health Fatal Accident Report, Explosives
and Breaking Agents, May 8, 1996
UNITED STATES DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Northeastern District
Metal and Nonmetal Mine Safety and Health
Accident Investigation Report
Surface Nonmetal Mine
Fatal Explosives Accident
Explo-Tech Incorporated
ID No. 36-02362-W21
at Miller Quarries
Division of Miller & Son Paving Incorporated
Rushland, Bucks County, Pennsylvania
May 8, 1996
Dennis A. Yesko, Supervisory Mine Safety and Health Inspector
Charles J. Weber, Mine Safety and Health Inspector
Special Investigator
and C. Okey Reitter, Jr., Supervisory Mine Safety and Health Inspector
Mine Safety and Health Administration
Northeastern District Office
230 Executive Drive, Suite 2
Cranberry Township, Pennsylvania 16066-6415
GENERAL INFORMATION
Gerald T. Little, truck driver/laborer, age 31, was fatally injured at
approximately 9:20 a.m. on May 8, 1996, when a non-electric down-hole primer
he was assembling detonated prematurely. Little was employed by Explo-Tech
Inc., an independent contractor that specialized in blasting. He had a total of 20
months mining experience as a truck driver/laborer with this contractor, 17
months of which included assisting the blaster in charge in assembling primers
and loading holes.
Little had last received annual refresher training on April 5, 1996, in
accordance with 30 CFR Part 48. This training addressed safe handling of the
various products utilized by Explo-Tech Inc., including protecting explosives from
impact.
PHYSICAL FACTORS
At the time of the accident, Little was assembling a non-electric down-hole
primer at the back of the explosives truck. The primer, which prematurely
detonated, consisted of either a Detaslide MS 450 or MS 500 delay detonator,
inserted into a 1-pound, [PETN /djh/] HDP-1 cast booster. The Detaslide
detonators contained a Remington .22 caliber rimfire casing held in an "L"
shaped plastic body. The MS 450 delays were manufactured on February 6,
1991, and the cast boosters were manufactured on April 1, 1996, both by Ensign-
Bickford. The MS 500 delays were manufactured on April 2, 1991, by Dupont.
Detaslide , Detaline detonating [shock cord /djh/] cord was used as the downline
initiation source for the detonators.
The manufacturer's product literature shipped with the detonators and cast
boosters instruct the user to fully insert the Detaslide detonator into the
capwell of the cast booster when assembling a primer. Also included was a
warning to never force or attempt to force a detonator into explosive material.
The rear of the 1978 Mack, R model explosives truck, V.I.N. R685T7216, was
provided with a bumper approximately 12 inches wide, extending the width of the
truck. This bumper served as a work platform for loading/unloading explosives,
and for assembling primers. It was constructed of a 2-by 10-inch oak board,
covered with a layer of -inch steel diamond plate, on top of which was a layer of -
inch aluminum diamond plate. One hole was blown through the left side of the
bumper. The opening measured approximately 10 inches through the aluminum
plate, and 5 inches in diameter through the steel plate and oak board.
Little was found approximately 10 feet from the rear of the truck. He had
sustained massive injures to the abdominal area of the body, and the upper
extremities. The pattern of damage to the bumper, and of the injuries to Little,
indicated that he was holding a primer with his left hand against the top, left side
of the bumper when it detonated.
On the rear of the explosives truck there were five bags of emulsifier, numerous
starters and surface delays, one damaged booster, and the remnants of several
boosters damaged in the explosion. Some other damaged explosive materials
were found approximately 75 feet from the truck. A wood handled steel knife,
used to cut the Detaline cord and slit bags of ammonium nitrate fuel oil (ANFO),
was found on the ground approximately 10 feet from the victim. A lead weight,
normally attached to a plastic measuring tape, used to measure the depth of the
boreholes, was also found on the ground near the rear of the truck. Many small
pieces of the measuring tape were found scattered about the scene.
The knife and lead weight were examined after the accident to determine if either
may have been used by Little to seat the detonator in the booster. The
preliminary results of the examination, however, were inconclusive. Two of Little's
co-workers stated that about 1 year prior to the accident, they had seen Little tap
on a detonator with a knife to seat it in a booster. At that time, both employees
said they had separately cautioned Little about this practice, and that Little had
told them he would not do it again. Neither employee had informed their
supervisor of Little's actions.
Examination of the detonators and cast boosters found at the accident site, and
at the contractor's explosive magazine, revealed that the detonators easily fit into
the capwell in all the boosters examined, with the exception of one booster
damaged by the explosion. Explo-Tech Inc. also provided additional Detaslide
detonators and HDP cast boosters for further examination and testing by MSHA.
Several of these MS 450 Detaslide detonators subsequently provided were found
to be slightly longer than the others examined. Sherman Hayes, sales manager,
and Ernest Leffler, blaster-in-charge, stated that about 9 years ago they had
experienced an instance where four cast boosters in one case had been
defective. The detonators could not be inserted because of malformed capwells
when the boosters were cast. The defective boosters were not used, and were
returned to the manufacturer.
MSHA also requested that the U.S. Department of Energy conduct testing of the
functional sensitivity of the detonators and boosters. Preliminary results of this
testing appear similar to tests conducted by the explosives manufacturer in 1985
and 1987, with the results indicating that the Detaslide detonators were not
unusually sensitive to impact.
There were no signs of lightning in the area at the time of the accident.
DESCRIPTION OF ACCIDENT
On the day of the accident, Gerald Little, victim, reported to work at
approximately 6:30 a.m., his normal starting time. He unloaded explosives from
the explosives truck until two of his co-workers and supervisor arrived. After
unloading the truck, Little assisted Ernest Leffler, blaster-in-charge, and H. Craig
Keck, blaster, in loading holes with primers and ANFO at the west end of the No.
5 production bench. Little then assisted Cliff Wood, truck driver, in repositioning
the dewatering truck on the bench, after which Little proceeded toward the rear of
the explosives truck.
At approximately 9:20 a.m., Leffler, Keck and Wood reported they heard an
explosion. Leffler said he looked up, saw a flash by the explosives truck, and
realized that a premature detonation had occurred. He ran around the driver's
side of the truck and found Little lying on the ground about 10 feet from the rear
of the truck. Little had sustained massive injuries and was killed instantly. Leffler
drove to the mine office where he reported the accident and 911 was called. A
local ambulance responded to the call. Little was pronounced dead at the scene
by the county deputy coroner.
CONCLUSION
Evidence indicated that the victim was assembling a primer, consisting of a
Detaslide detonator and an HDP-1 cast booster, on the rear bumper of the
explosives truck when it prematurely detonated. The detonation was apparently
caused when the primer assembly was subjected to impact. Co-workers stated,
that on two prior occasions, they had seen the victim tapping on a detonator with
a knife to seat it in a booster.
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holmes1880
dushbag
Posts: 194
Registered: 13-12-2010
Location: http://highexplosivesforum.forumotion.com/
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Wizard, chill out on posting- I can't read essays in every reply. Can you make 1 paragraph summaries? 
@BBarlog
Y chromosome is a small part of the mix. The common theme of people doing HE is they are white(White/Caucasian.......mostly Anglo-Saxon) and male.
Similarities end there. From there it's up to individual intelligence and maturity. I pile intelligence and maturity into one broad category I call
"IQ". There are various aspects that combine into overall intelligence. Kind of like the combination "clever" and "smart".
Btw, I've never seen women or black folks in amateur pyro. There must be discrimination! Hehe.
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