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holmes1880
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Detonation Safety Distance
I am particularly interested in appropriate critical safety distance from the explosive where you will not be harmed externally/internally from
the blast wave pressure/brisance. *Let us ignore the shrapnel aspect of this relationship, since shrapnel can get you even at 1km.
Nobody is planning to have an accident, but for any contingency procedure it is good to know what risk your are taking while handling energetics.
Sadly, the scientific research isn't substantial, so many things have to be based on precedents, personal tests.
Using 1g NG as the standard unit of measure, let's break down potential critical distances assuming extended arms' length measuring from the
fingertips:
0.1g.........1cm
0.5g.........3 cm
5g............10cm (ear and eye damage is plausible here)
50g..........50cm (ear and eye damage is very likely)
This was largely speculations but things we do know from reported accidents:
1. 0.2g ETN has minimal if any brisance at 2cm(I tested it)
2. 50ml of MEKP will not dismember wrist at 10cm nor take away vision or hearing (I'm not sure about this report because it could have been a
deflagration vs. full order)
3. 5-10g of TATP detonated in a metal container will not cause permanent loss of hearing or vision(not considering shrapnel).
4. Hitler survived 1kg of C4-type detonation being with 10 feet. 
Any contribution to this database is much appreciated.
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The WiZard is In
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Quote: Originally posted by holmes1880  | | I am particularly interested in appropriate critical safety distance from the explosive where you will not be harmed externally/internally from
the blast wave pressure/brisance. *Let us ignore the shrapnel aspect of this relationship, since shrapnel can get you even at 1km.
|
Let me take this where you probably never considered.
[I have a talent for this.]
YELVERTON, J.T. et al. 1973. Safe Distances from underwater
Explosions for Mammals and Birds. Lovelace Foundation for
Medical Educaticn and Research, Project Report:
DNA-NWED-M-012.
Or how about quail, chickens, geese or pigeons? –
Damon, E.G. The tolerance of Birds to Airblast. Project Report-
DNANWED-U99QAXM. Task A012. DH
If you are interested in effects ... and have a strong stomach...
eyeball —
J Rajs & et al
Explosion-Related Deaths in Sweden — A Forensic-Pathologic
and Criminalistic Study
Forensic Science International
34 (1987) 1-15
There is a tremendous amount of info available on blast trauma.
VII.10
Umbrella Effect of a Landmine Blast
War Surgery in Afganistan and Iraq : A Series of Cases, 2003-2007
SC Nessen & et al Editors
Office of the Surgeon General
US Army 2008
I a good reminder not to step on a landmine!
djh
---
Landmines are relative —
Between you and the enemy — Bad.
Between the enemy and you — Good.
© djh 2008
YOU will have to do the leg work.
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holmes1880
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Wizard, these are awesome sources As I skimmed the abstracts, I think I forgot
to include into consideration the damage to the lungs/hyperventilation death.
I did a 60g ANNM test few weeks ago, and IF something that powerful goes off 100cm away from you, breathing would definitely get constricted for quite
some time.....makes perfect sense.
[Edited on 26-12-2010 by holmes1880]
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grndpndr
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Blast injuries sound like a gruesome way to go if your not killed outright.Apparently air filled organs are the most subsceptible.Eardrums will be
the first to rupture,if thats all your lucky.Then I dont know?Whether damaged lungs that can show up 48hrs later as it begins to get difficult to
breath as your lungs fill w/fluid(white butterfly) or perhaps your intestines are perforated which will lead to sepsis ,blood poisoning..Slop painful
death. Gruesome stuff. Lots of factors involved besides overpressure,lenghth of the
blast overpressure-FAE,enclosed space such as a cave etc.
Likely why hitler survived,supposedly protected from direct blast by a hardwood divider in the heavy table.Not secluded in a bunker but what appeared
to be a home like structure w/windows etc.(Best of plans..)
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Blasty
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Many years ago I remember reading about a man who survived an explosion at an early dynamite factory. He was the plant's manager and was standing
about 4 meters away from a 900 lb batch of nitroglycerin that accidentally went off. All the workers expected that the guy had been killed. He was
actually literally "blown away" (i.e. he was sent flying through the air and landed on some trees!) by the explosion but survived to tell the tale.
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quicksilver
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Most all the points depicts one extreme lesson: the further the better. Anything you can do to put distance between you and the danger of energetic
blast creates a safety element. As distance increases, blast damage diminishes therefore the rules about handling the cap by the leads or the fuse;
keeping them away from vital areas of the body, etc. Distance becomes your "safety zone" more often than any other single issue.
There ARE scales that describe weight levels and proximity but they get back to that vital agenda.
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The WiZard is In
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| Quote: Originally posted by holmes1880 | | I am particularly interested in appropriate critical safety distance from the explosive where you will not be harmed externally/internally from
the blast wave pressure/brisance. *Let us ignore the shrapnel aspect of this relationship, since shrapnel can get you even at 1km.
|
To be killed by blast alone requires either a whole bunch of explosives or really bad luck.
Eyeballing my ever useful copy of —
Wound Ballistics
Office of the Surgeon General
Department of the Army 1962
[You can usually find copies for US $25 me thinks.]
NB - More than a few stomach turning photos. War is not pretty.
p. 105
@ 500 lbs peak pressure sq inch 50% killed
60-100 50% seriously injured.
15 eardrums ruptured
"At the nearest point, peak pressures would be between
seven and eight times greater on an object oriented at
right angles to the travel of the shock wave; at a distance
of 90 feet, the factor would be approximately four; and
at 150 feet about three."
Table 18 Peak pressure in pounds per square inch at
varying distances from point of detonation for
general-purpose bombs of various weights on a surface
parallel to direction of travel of shock wave.
At 30 feet 60 &c. &c.
100lb 17 4
500 80 6
1 000 200 20
2 000 400 50
4 000 1 000 170
---------
Deficiencies in the Testing and Classification of Dangerous Materials. J.E. Settles.
Annals New York Academy of Sciences
Volume 152, Art.1. Pages 199-205. 1968.
"A total of 103 persons suffered injuries in the 81 accidents. Seventy-eight fatalities
resulted from these 81 accidents.
"Of the 81 accidents included in this analysis, it was concluded that 23 of them
involved only fire, and the principal hazard was radiant heat. It was further concluded
that 44 of the accidents involved both fire and explosion. From information available, it
seemed justified to assume that no more then 14 of the accidents were characterized
by supersonic shock waves that would fall within the accepted definition of "detonating"
reactions.
"The 14 accidents in which detonating forces were present resulted in injuries to 35
persons and 34 fatalities. It appears from the information available that only one of
these 34 deaths resulted from the blast overpressures that are associated with a
detonating reaction. However, this one fatality was not the result of blast damage to
human tissue. Rather, the blast pressure caused this individual to be propelled as a
projectile. The other 33 persons who died in these 14 accidents were located at points
where the density of flying fragments, and in some cases, the lethal searing of radiant
heat were so great that their deaths were certain, even though there had been no blast
effects.
"A serious and disturbing inconsistency is related to the practice of accepting a "fire
hazard only" label on reactions of such violence and destructive energy as
medium-velocity detonation, low-velocity detonations, high-rate explosions,
medium-rate explosions, Iow-rate explosions, and even reactions that don't explode at
all but kill people by burning them to death."
djh
----
Don't worry about
the bullet with your
name on it — worry
about shrapnel labeled
occupant.
Murhpy's Laws of Combat
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holmes1880
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Wizard,
Am I understanding that the blast heat generated is more of a lethal factor than the detonation wave?
@Blasty,
900lbs of NG at 4m........naw, that's as about impossible to survive as it is a fall from a 20 story building. 900g, I'd go for, but not 900lbs.
[Edited on 26-12-2010 by holmes1880]
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The WiZard is In
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Never underestimate bad luck
Hirsch, AE & AK Ommaya
Lethal Effects on Man of Underwater Detonation of a Firecracker
AGARD Conf. Proc. 88:15-1 1971
A firecracker exploded in contact with the skin within six inches of the skull base in a
young man while he was swimming underwater. The resulant severe head injury and
death appeared to be directly related to this underwater explosion. Reconstruction
of the mechanics of his injury indicate that when the head is subjected to impact
energies between 440 and 1800 in-lb and impact impulse between 1.8 and 3.5 lb. sec.,
both skull fracture and brain injury can occur. (Authors abstract)
I came upon this in my ever useful copy of —
Shilling and Werts
Underwater Medicine and Related Sciences : A Guide to the Literature
2 vols. Plenum Publishing 1973
I have a copy of the paper here somewhere do not be
remembering from were/how I obtained it.
Speaking of diving - years ago when I SCUBA'd someone came out
with a diver recall device it was a large salute/firecracker
in a 35mm aluminium film can. Underwater it made a crack
sounded like a piece of monofilament breaking.
Speaking of SCUBA my three best memories are being ...
SCUBA diving at Cozumel - swimming behind some sweet young
thing... watch her gluteus maximus mussels move her legs.
With just a hint of swamp spinach showing from 'round
her what Shakespeare called a nest of spices, taint
i.e., taint AH - taint pussy. AKA chin rest. Joy, &c., &c.
Wall of the Cayman Isl. Amazing down 'bout the 3 ledge like
looking down into a vast ink bottle .. jet black. One day
the dive boats captain sez "I was down at 170 feet and I saw you!"
True - however, I didn't think it wise to tell him that I was coming
up from 2XX feet. I wanted to get the hand on my
depth gauge to touch the stop pin... At that depth with every
breath you could see a drop in the air pressure gauge on the tank
which was empty when I came up. One quick dive!
An who .... after lunch having maxed out the tables we dove
in shallow waters. Crystal clear water like swimming in a giant
bath tub.
Lunch upon this day was chili and cheesewiz... Gawd! Swimming
along dropping conch shells on sleeping spotted-eagle rays...
O' no ... its shit or die. Back to the surface ... no way am
I being able to return to the boat. Back to the bottom...
undo tank strap, pull down trunks, pull knees up to chest,
roll over and BLOWWWW followed by a could of masticated
beans floating on the current through the pristine waters.
Absolutely the most comfortable dump I have ever taken.
Diving with the seal in the Galapagos. Amazing animals
underwater! They swim up and look into your mask, if you put
your hand out they muzzle it like a dog, which is good as they
have canines that would shame a tiger! Burst you bubbles.
An underwater pas du deux.
Now back on topic... most info on charge size vs. blast over
pressure was done in connection with structures not humans.
In simulations of special weapon explosions large amounts
of ANFO and spheres of pentolite were detonated.
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The WiZard is In
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Noted in passing explosives underwater
The use of explosives underwater by diver is covered briefly in —
Ye. P. Shikanov, Editor
Spravochnik Vodolaza (Handbook for Divers)
Moscow, Voyenizdat 1973
321 pages.
English translation by Joint Publications Research Service,
JPRS 60691. Sold by the NTIS.
My useful copy of the
1970 U.S. Navy Diving Manual
NAVSHIPS 0994-001-9010
p.94 change 1.
Appx. total force of an underwater blast wave.
P= 13,000 (cube root) W
----------------------------
d
P = force in ponds per square inch
W = weight of explosives in pounds
d= distance of explosion from diver (feet)
A pressure of 500 psi is sufficient to cause injury to the lungs
and intestinal track. Associated details follow.
This is repeated in —
the NOAA Diving manual : Diving for Science and Technology
Manned Undersea Science and Technology Office
US Dept of Commerce
1975
US Gov. Printing Office
Not found
Handbook U.S. Navy Diving Operations
1 April 1974
NAVSHIPS 0994-009-6010
Nice book the pages are plastic so you can them out diving and
not worry 'bout them getting wet. Should take my copy and
rinse the saltwater off it!
NB — This search was limited to what I shelve.
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holmes1880
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Since a lot of underwater discussion is coming up, I have done a few underwater detonations, and I would NEVER dare to stick my arm in the water when
it goes off, let alone jump in for a quick dip. When doing it off the concrete bank, it is absolutely humbling how hard the shockwave hits the
reinforced concrete wall......it feels like someone drove a pick-up truck in it.
P.S. Wizard, that story about scuba dump was epic! I'd be concerned doing it at a depths.....I'm not sure how the pressure could affect things,
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The WiZard is In
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| Quote: Originally posted by holmes1880 |
P.S. Wizard, that story about scuba dump was epic! I'd be concerned doing it at a depths.....I'm not sure how the pressure could affect things, |
----
I have two on land dump stories. I will spare you (all of you) the sorted details!
There is a famous workman comp. case. A diver was in la
decompression chamber on the throne when someone outside
opened the wrong valve at the wrong time! Sucked his guts out
through his ..... YAHOOOO-OO! They couldn't remove him from
the chamber so they brought in a surgeon who operated on him
in situ!
I had suggested this to La Myth Busters as a follow up to their
airplane toilet myth....!
djh
----
Penthouse magazine founder Bob Guccione dies at 79 21x10
DALLAS – Bob Guccione tried the seminary and spent years trying to make it as an
artist before he found the niche that Hugh Hefner left for him in the late 1960s.
Where Hefner's Playboy magazine strove to surround its pinups with an upscale
image, Guccione aimed for something a little more direct with Penthouse.
Something a little more direct.
Gynecology through the picture study method comes to mind. /djh/
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The WiZard is In
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Back from the shelves - I had forgotten my favorite diving book
it is a fun read.
Nicholas B Zinkowski
Commercial Oil-Field Diving
Cornell Maritime Press
2nd edition 1978
Chapter 8 - Use of explosives.
p. 45 Personal Problems Underwater
"I have known many divers who habitually and unabashedly
urinate in their dress, considering it one of the evils of the
trade."
Well sure in a dry suit, however, in a wet suit — one of life's
greatest and free pleasures!
Anyone remember the scene with John Glenn while in his Mercury capsule. Movie "The Right Stuff"?
djh
----
The problem with
l'ivresse des grandes profondeurs
[rapture of the deep]
is that you cannot
lay-back and enjoy it
for fear of loosing control.
I remember one female
carbon based unit who
overtaken by it dropped
her camera. (Cozumel Isl.
QR Mexico.) Id following
behind (hers) swam down
and retrieved it. Then swam
up and brought her back to
the reality that she was way
tooooo deep and should ascend.
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holmes1880
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The pressure chamber incident is just....wow. I'm uncomfortable just thinking of what that could feel like.
I have a very useful inquiry/proposition for safety with charges. The particular explosive in mind is KinePak, where we basically add NM after the
initiator is already inserted in the charge. Assuming NM does not sensitize NH4NO3 right away (the key assumption), it gives time to safely insert the
initiator and then back up from the charge. The only thing to worry about is the small detonator. Any idea whether AN is #6cap sensitive immediately
after adding NM, or does it take a few minutes? I'll probably have to test it out, but hate to waste good charge if it fails, even though that's the
desired result.
I got the idea for this method from this video:
http://www.youtube.com/watch?v=nkYJ2-eDNEc
[Edited on 26-12-2010 by holmes1880]
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Sickman
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[rquote
@Blasty,
900lbs of NG at 4m........naw, that's as about impossible to survive as it is a fall from a 20 story building. 900g, I'd go for, but not 900lbs.
[Edited on 26-12-2010 by holmes1880][/rquote]
May have been a low order det.
50 psi seems to be the LD50 for human exposure to blast overpressure:
Blast waves and the human body
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The WiZard is In
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Curious most LOX uses an absorbent combustible. See —
US Bureau of Mines
RI 3169
Absorbents for Liquid-Oxygen Explosives
April, 1932
----
US Bureau of Mines
Technical Paper 294
Progress of Investigations on Liquid-Oxygen Explosives
1923
(Can be DL'd)
Number 52A5.
22.1% aluminium dust
77.9% wood pulp
Lead block 1.44 that of 40% dynamite. [Straight?]
I expect silicon would fail the $$$ test. I also would like
to know how they computed the power of their mixture.
For an interesting report on actual use of LOX in mining I commend —
MH Kurlya and GH Clevenge
Liquid-oxygen Explosives a Pachuca
Transactions American Institute of Mining, Metallurgical and
Petroleum Engineers
Presented at the New York meeting, February 1923. p. 271-340.
The on site LO2 plant produced 25 l. (27.5 kg, 60.6 lb per hour.)
The life of their cartilages max out at 11.5 minutes. As has
been stated - LOX explosives cartridges are the ultimate safety explosive —
after a few minutes they are no longer explosive.
I was thinking of magic - once it is explained it is no longer
magic. I own this paper because a few years back I found
a bound copy of the complete year for sale at a good price.
Upon receipt I dis-bound it. Currently I am unable to find
the residuum.
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The WiZard is In
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LOX Strength
Transactions American Institute of Mining, Metallurgical and
Petroleum Engineers
G St. J. Perrott
Properties of Liquid-oxygen Explosives 1925
p1248-1275
Table 6.—Propulsive Strength of L.O.X. Cartridges as Measured
by Ballistic Pendulum
Relative Strength by Volume Compared to Dynamite [40%]
1.16 Gas Black S, cartridge density 0.33
1.14 Four way tie.
1.13 One
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holmes1880
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So, no info on how long it takes for NM to sensitize AN? Gerald Hurst's patent is no help, I skimmed it, and ............................nothing
regarding duration.
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Blasty
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"Compare our next nitroglycerine incident. In 1886 Mr. Wilson P. Foss was manager of the Clinton Dynamite Company's plant at Plattsburgh, New York. He
was inside a building and standing four yards from a wash tank that contained 900 lbs of nitroglycerine when an accidental gush of live steam from an
open valve detonated the nitroglycerine, destroying the building and leaving a crater 30 ft deep. Workers at the plant hurried to the site, expecting
to find Mr. Foss's remains among the wreckage. He had, however, been blown by the force of the explosion out of sight round the bend of a nearby
frozen river, and to the startled incredulity of the workforce he reappeared to them striding on the ice around the river bend." - John Bond, "The
hazards of life and all that: a look at some accidents and safety curiosities, past and present", CRC Press, 1996. Page 63.
| Quote: | | as it is a fall from a 20 story building. |
http://untoldvalor.blogspot.com/2007/07/alan-mcgee-luckiest-...
Don't underestimate the quite frankly bizarre survival luck some people have had.
[Edited on 27-12-2010 by Blasty]
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crazedguy
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@ Blasty: The guy surviving 900 lbs of NG seems believable to be so close you are pushed with the pressure wave rather than crushed by it, but I have
heard that story of the 20,000 foot fall before and find a piece of glass slowing the impact enough to save someones life hard to believe.
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simply RED
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"50g..........50cm"
Hahahahaha, that made my day....
When logic and proportion have fallen sloppy dead...
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The WiZard is In
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| Quote: Originally posted by crazedguy | | @ Blasty: The guy surviving 900 lbs of NG seems believable to be so close you are pushed with the pressure wave rather than crushed by it, but I have
heard that story of the 20,000 foot fall before and find a piece of glass slowing the impact enough to save someones life hard to believe.
|
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Well the 900 NG story is A- true and B- has nuances. There being a
good description in Vangleder and Schlatter, I will scan it after
I finish reading the news on line and going out in the 6.3o F
cold to move some of the snow around.
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bbartlog
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Thing with 900 lbs of NG, one could readily believe that there might be some initial deflagration that would push the victim/survivor fast and far
enough that once the DDT occurred he was already underway, so to speak, and thus at a distance where the real shockwave only accelerated him rather
than crushing him to death. In cases like these our theoretical models about what should happen must give way to actual reports.
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The WiZard is In
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| Quote: Originally posted by The WiZard is In | | Quote: Originally posted by crazedguy | | @ Blasty: The guy surviving 900 lbs of NG seems believable to be so close you are pushed with the pressure wave rather than crushed by it, but I have
heard that story of the 20,000 foot fall before and find a piece of glass slowing the impact enough to save someones life hard to believe.
|
------
Well the 900 NG story is A- true and B- has nuances. There being a
good description in Vangleder and Schlatter, I will scan it after
I finish reading the news on line and going out in the 6.3o F
cold to move some of the snow around. |
Finished moving the snow around, you should have seen the
smile on the Snow Man's face when he heard the snow blower
coming!
Broke the plow blade off my Gator, snapped 1/2" bolt, large
spring flew off into the snow, hope to find it comes April of May.
   \
I shelve a 1998 Ayer Company aka Arno Press reprint of G & S 1927.
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Jimbo Jones
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Nice way to clean your ear wax.
By the way, Hitler “survived, as did everyone else who was shielded from the blast by the conference table leg.”
The lightweight, wooden structure of the building loses even more from the performance of the used “plastic explosive”. If this 1 kilo was placed
in bunker…..
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