Magnesium alloys in pyrotechnics

2. Ammunition
Hazards Ammunition fires are among the most feared because of their potential destructive possibilities by detonation. Where ammunition is involved, fire prevention is doubly important, since many of the fires involving explosives and ammunition are preventable. It is the duty of fire-protection personnel and personnel handling ammunition to study the causes of fire so they will know the safety precautions which must be taken to prevent fires,
a. Heat
A great hazard in an around explosives is heat.
(1) Some explosives ignite at temperatures substantially lower than those required to ignite wood, paper, or fabrics. The ignition of explosives frequently results in violent reactions. Every effort must be made to maintain normal temperatures around ammunition and explosives.
(2) Fires in ammunition dump areas may be due to a number of causes. The following are moat common: dry grass, leaves, and underbrush ignited by sparks from locomotives, carelessly discarded cigarettes, campfires, or unprotected smokestacks.
b. Deterioration.
Deterioration of explosives and ammunition normally occurs at such a slow rate that most of them remain serviceable for many years. Under unfavorable conditions, explosives and ammunition which are deteriorating pick up heat so fast that it cannot be dissipated, and the explosives and ammunition may burst into flames as a result. An explosion or detonation may also result when deteriorating explosive or ammunition is confined too closely. A definite safety hazard results when repacking, renovation, and salvage operations are not property supervised and conducted in accordance with recognized standards.
c. Common Safety Violations.
Among the more common sources of fire hazards are excessive quantities of powder and loose explosives, accumulation of wastepaper, broken boxes, unauthorized use of spark-producing tools, defective machinery, faulty electrical equipment, and failure to provide the proper barricades and firebreaks necessary to prevent the spread of fire from one operation to another.
(1) Lack of training and violations of instructions or written regulations are frequently responsible for serious consequences. The most common violations include smoking, carrying matches in forbidden areas or buildings, and tampering with explosives or ammunition, particular, ly grenades or fuzes.
(2) Failure to understand and carefully observe the safety precautions prescribed for destroying ammunition and explosives might cause grass fires or explode nearby ammunition piles which are awaiting destruction. The most frequent sauce of these troubles is flying fragments released upon detonation.
d. Sparks.
Sparks may be created by striking iron or steel nails or metal containers against iron or steel tools, or by nails in shoes striking flint, pebbles, sand grains, or nails in the floor. Such sparks, small as they are, have caused disastrous explosions of black powder and have exploded the dust from other easily ignited !powders. This hazard is the prilme reason for requiring tools o f brass, copper, or other non-sparking materials. It is recommended that mud or dirt be cleaned from shoes before entering magazines that contain exposed explosives. Also sparks from a faulty car or truck muffler may cause an explosion.
e. Static Electricity.
Charges of static electricity can be accumulated on a person and on explosive material such as smokeless powder. The discharge of static electricity is a serious hazard in the presence of certain exposed explosives, dust and air mixtures, and flammable vapor-air mixtures. Processing equipment for such materials subject to static discharge should be electrically grounded, benches and flooring should be covered with electrically grounded conductive material, and personnel should be provided with safety shoes af an authorized type. Cushioned metal chairs should not be used in locations where explosives or highly flammable materials are present. The failure to control safely the use of heat and flame-producing equipment offers a constant hazard.
f. Lightning.
Lightning may strike buildings, trees, or other objects in or near explosive areas. Buildings and structures in storage areas should have complete lighting protection where conditions permit.
g. Transmission Lines.
Electric transmission lines are often blown down on or come in contact with combustible material. These lines should be periodically checked for condition and security of installation. When it is neceseary to install power transmission and service lines in the vicinity of the buildings containing explosives, the distance from the lines to the buildings must be greater than the distance between the poles which support the lines. This precaution is necessary to prevent falling wires from coming in contact with the building. Overhead transmission lines must not pass within 50 feet (15 meters) of the building. In future installations power lines and services which enter buildings containing explosives must be placed underground within 50 feet (15 meters) of the building. h. Vegetation. Vegetation (such as grass, undergrowth, weeds, etc.), which is or may become a fire hazard, should be controlled by using a chemical weed killer, by mowing, plowing, cutting, livestock grazing, or, in calm weather and with the proper control, by burning.
(1) Chemical weed killers should not contain chlorates or other substances which may ignite spontaneously under hot, dry conditions or by friction.
(2) Burning should not be permitted within 50 feet (15 meters) of any earth’ covered magazine containing explosives or ammunition, or within 200 feet (61 meters) of any above ground type magazine or outdoor storage ,pad. Brush, grass, wood, etc., gathered in piles, will not be burned within 200 feet (61 meters) of a magazine. Reserve supplies of dunnage, consisting of wood or other materials packed between explosives to prevent vibration or chafing, should not be stored hapazardly inside the magazine area. In no case may it be sotred within the 60-foot (16- meter) firebreak around the magazine.
(3) A firebreak at lea& 50 feet (15 meters) wide and as free as practicable from flammable material will be constantly maintained around each aboveground magazine. The earth adjacent to and extending over igloo magazines should be cleared of dry debris. Firebreaks around the entire magazine area and at other locations within the magazine area, such as along railroad tracks, must be maintained whenever necessary. i. Trains. Locomotives, trains, and other rail vehicles used in the magazine ,area must be equipped so that the communication of fire will be prevented as far as [practicable. Inspections should ,be made regularly to insure that safe conditions are maintained.
j. Cleaning Fluids.
Gasoline or other highly flammable liquids should never be used for cleaning. Solvent, dry-cleaning (Federal Specification), must be used when cleaning solvents are required.
k. Smoking.
Fire prevention regulations state that matches or other flame-or spark-producing devices are not permitted in any magazine or explosive area except by written authority of the commanding officer. Smoking is prohibited in any magazine or magazine area, or in the vicinity of cars, wagons, motor trucks, or boats in which there are explosives or ammunition. Buildings or locations for smoking may be designated outside restricted areas subject to certain limitations ; smoking will not be allowed in locations closer than 60 feet (18 meters) to buildings containing explosives, ammunition, or other hazardous materials.
l. Miscellaneous Hazards.
(1) When buildings close to explosive or ammunition areas are approved for smoking, windows and doors must be fitted with wire screens.
(2) Suitable receptacles must be provided for cigarette and cigar butts and pipe ashes.
(3) Only permanently installed electric lighters of approved types may be used in the building.
(4) Portable fire extinguishers, sandboxes, and water barrels with buckets must be furnished as required for each room or building in which smoking is permitted.
(5) Persons wearing clothing contaminated with explosives or other hazardous materials will not be permitted in such areas.
(6) Automobile parking should be regulated so that vehicles will not be parked within 25 feet (7.7 meters) of fire hydrants and should use designated areas only.
(7) All flashlights or storage-battery lamps used in buildings containing explosives or flammable vapors must be safety-approved types for that specific type of exposure.
(8) Ordnance safety requirements must be complied with if gasoline- or electric-powered lift trucks are used for transporting ammunition or explosives.

3. Preventive Measures
Occasional fires may reasonably be expected, no matter how careful personnel are with flammable materials. But, by following the principle that “an ounce of prevention is worth a pound of cure,” the number of fires can be greatly reduced. Below is a brief discussion of some of the measures that can be taken.
a. Stacking.
Ammunition boxes, containers, dunnage, and lumber must be stacked in an orderly manner when in the vicinity of explosive ehandling or storage operations. Stacks of such combustible materials must be limited to small areas between firebreaks. Additional factors to consider in limiting the spread of fire are the available space for combustibles, the availability of fire-extinguishing facilities, and the probability of fire. Under average conditions, areas under solid stacks of such materials should be limited to 1,500 square feet (139 square meters), separated from other similar areas by 50-foot (15-meter) firebreaks in which vegetation has been cut and controlled. Bulk stacks of such materials should not be located within 500 feet (152 meters) of magazines or other buildings containing high explosives. Working quantities, within feasible limits, may be stacked in the vicinity of explosive magazines but not closer than 60 feet (16 meters). Water barrels and pails should be liberally provided in such areas for extinguishing beginning fires. Additional rules may be issued as the commanding officer deems necessary to secure the fire protection local conditions demand.
b. Portablee Extinguishers.
A fire involving explosives or ammunition produces a conflagration (major fire) or explosion very quickly; therefore, means for attacking the first small blaze detected are vitally important.
(1) Immediate use must be made of portable extinguishers and other hand equipment. In addition to organized permanent facilities, barrels and buckets filled with water should be placed at each magazine. This type of fire protection, when properly maintained and utilized, may ‘be extremely valuable in explosive storage areas having open storage pads or combustible storage magazines. During hot weather the barrel must be refilled frequently ; in freezing weather calcium chloride or salt must be added. Buckets deteriorate rapidly unless they are frequently painted or protected from the weather. They may be blown about by windstorms if they are not securely fastened in place. Fastening devices must be easily releasable.
(2) Boxes and buckets filled with sand (with shovels located nearby) are useful in isolating, checking, or extinguishing beginning fires. To combat grass or forest fires in or near the magazine areas, an adequute supply of gunnysacks, brooms, rakes, hoes, or other similar equipment must be maintained at suitable locations. This equipment should be regularly inspected and protected against theft or unauthorized use.
(3) When explosives and ammunition are being handled, or work is being done in the immediate vicinity of such stores, two portable fire extinguishers of adequate size and rating must be ready for immediate use. It is not necessary that these extinguishers be located permanently in a magazine. Portable extinguishers must be placed in the most accessible location. Serious fires may be prevented by the prompt use of hand fire extinguishers. They are required primarily for use on beginning fires of inert combustibles, such as grass, grease, oil, dunnage, etc., which, if not extinguished, may reach explosives. Personnel other than the individual using the extinguisher should seek safety immediately and report the fire.
c. Water Distribution System.
The water distribution system should be .protected by sectional control valves so that damaged sections of the main can be cut off without impairing the operation of the remainder of the system. Water mains should not be located under railroads or roads used for transporting large quantities of explosives or ammunition, because a detonation may break the main. When it is necessary to have water mains pass under railroads or roads, cars or trucks loaded with ammunition must not remain over these water mains longer than necessary for continuous travel. Suitable signs must be posted to indicate such a location. Water mains should be protected with cutoff valves on both sides of the railroad or road. Fire hydrants should be connected to a looped grid system to provide a supply from more than one direction.
d. Fire-Protection Personnel.
The duties of firefighters, guards, military personnel, and others should be arranged so that an adequate fire fighting force is available at all times.
(1) Fire drills and fired prevention inspections should be carefully conducted to insure that firefighting forces understand their specific duties and that firefighting equipment functions dependably under actual working conditions.
(2) Fires that occur in buildings or magazines containing explosives vary in intensity and effect, depending on the material involved in the fire. Certain explosives may detonate or explode immediately on contact with a spark or flame or when subjected to frictional heat or concussion. Fire may or may not result from the detonation. Some explosive substances burn freely while others may explode while burning. Some substances develop such intense heat, as in the case of smokeless powder, that firefighting efforts are impossible. Firefighting forces should be well acquainted with the hazards and best methods of combating fires in all such materials under their protection.
(3) With certain rare exceptions, water is used as the firefighting medium. Generally speaking, for extinguishing explosive fires, large volumes of water spray or fog, produced by special nozzles with large range and volume capacities, prove more efficient than solid streams of water. Solid streams of water at higher pressures and great range should be used when consideration for the safety of firefighting personnel makes it impossible to approach the seat of the fire. Training programs should emphalsize the importance of laying as many hose lines as practical in order to surround the fire completely and to extinguish it rapidly. When an explosion is imminent, firefighters must seek shelter or lie close to the ground when directing long-range water streams to the fire.
(4) Guards and watchmen should be instructed that when smoke is discovered coming from a closed magazine or when there is other evidence that the magazine is afire, the alarm must be given as quickly as possible. A single guard on duty will not enter the building, since he may become trapped and unable to give the alarm. If the. fire is discovered in the grass or other combustible material surrounding the magazine, the alarm should be given immediately. The guard should then do all that is possible, using extinguishers, water from nearby water barrels, or grass firefighting tools, to extinguish or control the fire until firefighting forces arrive.
(5) When a workman or some other person discovers a fire where personnel are working and explosives are present, the personnel should be evacuated by a signal in accordance with prearranged plans. At least one responsible messenger should be dispatched in the direction from which the fire department is expected in order to inform them of the nature and extent of the fire. The officer in charge of firefighters must not permit the advance of his men to such a fire unless he has what he believes to be accurate information as to the existing conditions and concludes there from that he is justified in so doing.
(6) Firefighting forces should attack a grass fire vigorously and try to extinguish it even when it is burning in the vicinity of a magazine. If a fire has actually gained headway in a magazine, firefighting forces should either combat the fire or seek the nearest suitable protection, depending on the type of ammunition or explosives within the magazine.