Magazine floors stained with nitroglycerin shall be cleaned according to instructions by the manufacturer. Only experienced persons shall be allowed to do the work of destroying explosives. In making outside repairs, if there is a possibility of causing sparks or fire the explosives shall be removed from the magazine. Explosives removed from a magazine under repair shall either be placed in another magazine or placed a safe distance from the magazine where they shall be properly guarded and protected until repairs have been completed, when they shall be returned to the magazine.
The land surrounding a magazine shall be kept clear of all combustible materials for a distance of at least 25 feet. Combustible materials shall not be stored within 50 feet of magazines. Caps recovered from blasting misfires shall not be reused. Such explosives and caps shall then be disposed of in the manner recommended by the manufacturer. In the event of breakdown or collision the local fire and police departments shall be promptly notified to help safeguard such emergencies.
Explosives shall be transferred from the disabled vehicle to another only, when proper and qualified supervision is provided. If vehicles do not have a closed body, the body shall be covered with a flameproof and moistureproof tarpaulin or other effective protection against moisture and sparks.
All vehicles used for the transportation of explosives shall have tight floors and any exposed spark-producing metal on the inside of the body shall be covered with wood or other nonsparking materials to prevent contact with packages of explosives. Packages of explosives shall not be loaded above the sides of an open-body vehicle. Class B explosives. Explosives, Class B, and quantity. Explosives B Red letters on white background. Oxidizing material blasting Oxidizers Yellow letters agents, ammonium nitrate, etc.
The front marking or placard may be displayed on the front of either the truck, truck body, truck tractor or the trailer.
Refer to Extinguishers shall be examined periodically by a competent person. This attendant shall have been made aware of the class of the explosive material in the vehicle and of its inherent dangers, and shall have been instructed in the measures and procedures to be followed in order to protect the public from those dangers.
He shall have been made familiar with the vehicle he is assigned, and shall be trained, supplied with the necessary means, and authorized to move the vehicle when required.
Department of Transportation regulations. Where routes through congested areas have been designated by local authorities such routes shall be followed.
No person shall be allowed to handle explosives while under the influence of intoxicating liquors, narcotics, or other dangerous drugs. Verbal notice shall be confirmed with written notice. These precautions shall include:. In opening kegs or wooden cases, no sparking metal tools shall be used; wooden wedges and either wood, fiber or rubber mallets shall be used. Nonsparking metallic slitters may be used for opening fiberboard cases.
Violent tamping shall be avoided. Primed cartridges shall not be tamped. After loading, all remaining explosives shall be immediately returned to an authorized magazine. All primers shall be assembled at least 50 feet from any magazine. If electric blasting caps are used and a misfire occurs, this waiting period may be reduced to 30 minutes. Misfires shall be handled under the direction of the person in charge of the blasting and all wires shall be carefully traced and search made for unexploded charges.
Leading wires shall remain shorted and not be connected to the blasting machine or other source of current until the charge is to be fired. All direct sources of heat shall be provided exclusively from units located outside the mixing building.
The exhaust systems on all such engines shall be located so any spark emission cannot be a hazard to any materials in or adjacent to the plant.
All bearings and drive assemblies shall be mounted outside the mixer and protected against the accumulation of dust. All surfaces shall be accessible for cleaning.
In gravity flow systems an automatic spring-loaded shutoff valve with fusible link shall be installed. Solid fuels shall be used in such manner as to minimize dust explosion hazards. The frame of the mixer and all other equipment that may be used shall be electrically bonded and be provided with a continuous path to the ground.
Shafts or axles which contact the product shall have outboard bearings with 1-inch minimum clearance between the bearings and the outside of the product container. Particular attention shall be given to the clearances on all moving parts.
These include the placarding requirements as specified by Department of Transportation. The employer shall assure that the operator is familiar with the commodities being delivered and the general procedure for handling emergency situations. The employer shall assure that the driver, in moving the vehicle, has assistance of a second person to guide his movements. Provision shall also be made so that the gate can be locked. They shall be designed to minimize damage from corrosion.
Table H shall be used in determining separation distances from inhabited buildings, passenger railways, and public highways. These distances allow for the possibility of high velocity metal fragments from mixers, hoppers, truck bodies, sheet metal structures, metal container, and the like which may enclose the "donor". Where storage is in bullet-resistant magazines recommended for explosives or where the storage is protected by a bullet-resistant wall, distances, and barricade thicknesses in excess of those prescribed in Table H are not required.
Footnote 4 These distances apply to nitro-carbo-nitrates and blasting agents which pass the insensitivity test prescribed in the U. Department of Transportation DOT regulations.
Footnote 5 Earth, or sand dikes, or enclosures filled with the prescribed minimum thickness of earth or sand are acceptable artificial barricades. Natural barricades, such as hills or timber of sufficient density that the surrounding exposures which require protection cannot be seen from the "donor" when the trees are bare of leaves, are also acceptable. Footnote 6 When the ammonium nitrate must be counted in determining the distances to be maintained from inhabited buildings, passenger railways and public highways, it may be counted at one-half its actual weight because its blast effect is lower.
Any of you hear about the guy who invented nitroglycerin? Probably not! His lab assistance came into the room, saw that his mentor had detonated, and he said; "huh, I guess this stuff does work". Leslie Arzt Daniel Roebuck accompanies the team venturing to the Black Rock to assist in the retrieval of dynamite to blast open the mysterious hatch. After Arzt wraps a stick of dynamite in Kate's wet shirt, he waves the dynamite by accident , which explodes in his hands, killing him instantly.
History: The Italian chemist Ascanio Sobrero first made nitroglycerin in , by adding glycerol to a mixture of concentrated nitric and sulfuric acids. Terrified of his discovery he considered nitroglycerin to be too dangerous for practical use as the impure compound was liable to explode without warning. A Nobel Discovery: Swedish scientist and industrialist Alfred Nobel studied these problems and worked hard to improve nitroglycerin as a means for blasting rock and thus used as a tool for mining.
In the s he discovered that when the compound was combined with silica it could be turned into a paste and kneaded into shapes. This is frequently referred to as dynamite. Discontent: Sobrero was m ortified when Nobel began the commercial exploitation of nitroglycerin and due to the success of dynamite; the Italian felt he had been subject to an injustice. Although Nobel openly cited Sobrero as the inventor of nitroglycerin, Sobrero quoted: " When I think of all the victims killed during nitroglycerin explosions, and the terrible havoc that has been wreaked, which in all probability will continue to occur in the future, I am almost ashamed to admit to be its discoverer ".
Nitroglycerin is derived from glycerol highlighted in red ; where all the OH groups have be replaced with NO 2. Glycerol is a common biological molecule from which triglycerides fats in animals and oils in plants are assembled. Properties: This heavy, colourless, toxic oil, that is so unstable that the slightest jolt, impact or friction can result in spontaneous detonation.
Although explosive in the liquid state, the solid is much less sensitive to shock and therefore more stable freezes at approx. It is obtained by nitrating glycerol and is used in the manufacture of explosives, specifically dynamite. Click on the picture above to interact with the 3D model of the Nitroglycerin structure. Instability and Explosive Nature. As nitroglycerin contains oxygen, nitrogen and carbon, an explosion is essentially rapid combustion - the three nitrate groups powerful oxidizing agents are bound directly to a hydrocarbon fragment a fuel.
Those are very much my department, yes. And Mark Lancaster makes them as well. I've made a six-inch one, and he's made an even bigger one, the eight-inch one. Perhaps when I get out, I'll be able to make those as well. But, not yet. To launch it, you actually put it inside this eight-inch mortar and lower it all the way down to the bottom, and that means that this mortar will fire the shot for about a thousand feet, and then it explodes, does at least three interesting things before going out, and has a spread of about three hundred feet.
So, it's a pretty serious firework. You have to remember that you're standing on a very small, hollow, steel barge with about four tons of explosive surrounding you with nowhere to run, nowhere to hide, and once it starts going off, the whole barge can move up to six inches down in the water. The sound is unbelievable. It's wonderful. You really feel as if you have entertained and earned your keep for the day.
Indeed, the tarnished history of explosives has been dominated by dangerous experiments that many perpetrators vainly hoped would never be repeated. The man who lit the fuse of European warfare was an English friar who perfected more explosive blends of gunpowder. Medieval travellers from the east probably brought the basic recipe to Europe. Gunpowder consists of three ingredients.
The most important is the white powder called saltpeter. Its modern name is potassium nitrate. It contains chemically-bound oxygen that supports rapid burning of the two fuels, sulphur and charcoal. Properly refined and mixed, they form an explosive mixture originally called "black powder. Making it explode, much harder. The secret lay in the quality of the saltpeter. It causes the fire to burn very fiercely locally, to generate sparks. And the greater the extent to which saltpeter is purified, the more violent this reaction.
Saltpeter is very often the white stuff that you can scrape, very fine crystals, from the walls of cellars. It's also the stuff that can—that oozes out of piles of soil and earth contaminated with vegetable rubbish. Roger Bacon found a way of purifying the brown sludge by concentrating the mixture and crystallizing out the white powder. Many of the things Roger Bacon tried in , Sidney Alford repeated as a schoolboy in By increasing the ratio of saltpeter to charcoal and confining the powder in a paper tube, he discovered an extraordinary property.
Bacon had made his first bang. Roger Bacon was a scholar who laid the foundations for modern science. He always wrote up his experiments, but his black powder investigations frightened him. He foresaw the dangers if this formulation fell into the wrong hands and decided to encode the recipe in an anagram in the Latin text.
The passage ends with the words, "And so thou wilt call up thunder and destruction if thou know the art. He knew that the more the powder was confined, the bigger the explosion.
Roger Bacon didn't understand the chemistry, but what happens when gunpowder ignites is a violent transformation of solid ingredients into a rapidly-expanding mixture of hot gasses. If trapped inside a container, they will also cause an explosion.
The effect will be rather different, and I think it would be a good idea to do this outside. This enhanced confinement will increase the speed of burning. So quite a high pressure can develop and should give more oomph, to use a technical expression. Five, four, three, two, one. It was the death knell of the old feudal system based on the stone castle, the mounted knights, and so on, and the whole social system that went with that. And what it meant was that the people who could dispose of the power to produce gunpowder weapons were the ones who could control society.
Because it will only explode when confined, it's called a low explosive. But there's a different type of explosive that will unleash its fury in the open without confinement.
This unstable oil has fuel and oxygen chemically combined in one molecule. Its name is nitroglycerine. It's a high explosive which can be triggered by a hammer blow. Gunpowder essentially burns. People in the trade use a fancy Latin word for it: deflagration. But it means no more than "burns. Not only does that material contain much more chemical energy for a given mass, but also, it decomposes very much more quickly.
And this makes the explosion much more violent. NARRATOR: The first high explosives were discovered by accident in the nineteenth century when chemists began adding nitric acid to organic compounds to make new medicines. The Italian scientist, Esconio Suprero, started experiments with organic glycerine.
He created a new oxygen-rich compound: nitroglycerine. He did not realize how dangerous this liquid was until his lab exploded. Many chemists have been mauled by this beast. It held an irresistible fascination. Certainly, he would have suffered a very severe headache through tasting the nitroglycerine. The power of nitroglycerine far surpassed other explosive materials.
Yes, I suppose it did have a—a certain attraction. But, being a liquid material, it wasn't very easily handled and it wasn't very safely handled. The way to make an explosive is to store chemical energy inasmuch as possible. And so, if you have hydrocarbon material and you put nitro groups on it, that sort of winds up a spring, stores potential chemical energy in there.
The more you put on a molecule, the more energy there is. And it's—It's just that—That's a good way to store a lot of energy in the molecule. For me, it's no school boys. It's called nitrogen trioxide. Now, this is an explosive composed of nitrogen and iodine in a very unhappy relationship.
And I describe it as being a very unhappy marriage. These elements are just waiting for an excuse to suddenly burst apart, they're so sensitive. So sensitive that even a fly running on it might set it off. So, if you'll kindly put on your ear protection and your eye protection, I'll now demonstrate. To capture a moment of detonation on film requires a camera that can run at a million frames per second. Whereas the term a "low explosive" refers to something that's merely burning very fast.
And that can be very fast. That could be burning at speeds of maybe a thousand meters per second, but it's still just a fast burn. It isn't actually detonating. The process of detonation is a very specific and different phenomenon. And as that goes through some of the explosive material, it compresses it, which heats it and raises its pressure, and so the reactions, the chemical reactions, start going faster and faster. When the chemical reaction accelerates, it drives the shock wave at supersonic speed.
DOUGLAS OLSEN: The chemical reactions behind the shock wave give it the push that keeps it going, and you can produce pressures that are like a hundred thousand atmospheres, which can go through—You know, can make holes in steel plates and you can do useful things with it. It's almost full of explosive, and it has a metal cone in the front. They line up, forming a sort of slug, and it will travel very, very fast.
Four, three, two, one. Well, one set of steel, one rotten rod? The copper cone, which was about that diameter, four inches in diameter, was squeezed down to a projectile of about one and a half inches in diameter, and it was travelling extremely fast, several times the speed of a rifle bullet.
It would have penetrated this at tens if not hundreds of meters of range. And this is mild steel. It does it on armor. Back at the New Mexico test range, they investigate the characteristics of different explosives. In this case, they want to see if the shell can be accidentally detonated by a stray fragment from a bomb blast. To avoid accidents, most modern explosives are designed to be difficult to set off, but they need to be tested to make sure. Using a sled track, the engineers will fire a lump of metal on the end of a rocket to simulate debris hitting the warhead at high velocity.
The unpredictability of high explosives has always been a problem since investigations first began. The father of high explosives was Alfred Nobel, the Swedish industrialist. In the s, gunpowder was the only available explosive, so the commercial potential for something more powerful, like nitroglycerine, was clear.
But its tendency to explode without warning made it too dangerous to handle. On the contrary, it can provide a powerful stimulant for them to tame a dangerous substance or instrument. If you look at the work with the atom bomb and so on, you find the same. Madame Curie and radium, and so on.
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