UNDERSTANDING DEPARTMENT OF DEFENSE FIRE SYMBOLS
During the Desert Storm operations buildup, the need for military strength increased. All across America, military munitions were being transported from one defense base to another. These munitions were stored and stockpiled at different locations, awaiting transport overseas.
Even without the threat of war, munitions are traveling across the highways daily; military installations store them for use in training maneuvers and for emergency aggression flights. Transporters on extended trips between bases may have to stop and store the munitions temporarily on an installation that normally does not use munitions. Should an accident that involves fire in such a facility, a rail car, or a truck occur, emergency responders should be aware of the potential dangers munitions present when exposed to fire conditions.
While on the military installation, the storage unit for munitions is required to be placarded with an appropriate fire symbol. Understanding the Department of Defense (DOD) fire symbols is important for firefighters dealing with military munitions. Placarding requirements for explosiveladen facilities are outlined in the Department of Defense Directive (DODD) 6055.9 and the DOD Ammunition and Explosive Safety Standards outlined in DOD Standard 6055.9, and they agree with Occupational Safety and Health Administration (OSHA) Standard 1910.109.
The Department of Defense fire symbol system used with conventional munitions alerts firefighters to specific hazards. The symbols use a combination of geometric shapes, numerals, and colors to designate the hazards. The symbols cover two categories of military munitions: conventional munitions and chemical munitions.
CONVENTIONAL MUNITIONS
Conventional munitions are placed under Class 1/Explosives with the United Nations (UN) number and Department of Transportation (DOT) title, respectively. The DOI) breaks the classification down into four divisions. 1 through t of its own system (similar but not identical to the UN/ 1MCO system) The four divisions are represented by the symbols made up primarily of shapes and numerals. Verbally and numerically, they are referred to as follows: Class I Division 1 (II); Class I Division 2 (1.2); Class 1 Division 3 (1.3); and Class 1 Division i (It). Frequently, they are referred to as fire symbol (F/S) 1. 2, 3, and 4. Hie hazard decreases as the number increases. Fire symbols, except for fire symbol 1. do not apply to liquid propellants. Fire symbol 1 indicates a propellant’s detonation hazard. All four placards are orange with black numerals. The orange background signifies the presence of an explosive hazard. The DOD fire symbol class/ division translates into the Department of Transportation placard system as follows:
- Fire Symbol-Class l Division 1 = DOT Explosive 1.1 placard.
- Fire Symbol-Class 1 Division 2 = DOT Explosive 1.2 placard.
- Fire Symbol-Class 1 Division 3 = DOT Explosive 1.3 placard.
- Fire Symbol-Class 1 Division 4 = DOT Explosive 1.4 placard.
This cross-reference is for transporting munitions off the military installation. The DOT placard referenced here was implemented in October 1991. Propellants for munitions are covered under F/S 3 and are placarded with the corresponding DOT placard.
Class 1 Division 1 (1.1). Fire symbol 1 represents a mass detonation hazard. Mass detonation is typical of high-explosive munitions. Its characteristics are total destruction with sonic shock waves. The symbol is in the shape of an octagon, the same shape as a stop sign. The black numeral 1 is in the orange octagon.
The minimum public withdrawal distances for an accident depend on whether the event involves fire or whether the contents and quantities of the explosives are known. If no fire is involved, the senior fire official determines whether to implement the minimum withdrawal distance criteria.
Should the accident involve fire of an explosive-laden facility, a tractor trailer, a cargo truck, or a rail car of unknown explosive contents, minimum withdrawal will be ⅝ mile for a facility, tractor trailer, or cargo truck and one mile for a rail car. For accidents involving fire of an explosiveladen tractor trailer, cargo truck, or rail car of known content or quantity of a fire symbol 1 material, the minimum distance is not less than 1,250 feet for nonfragmenting munitions.
Note: These are minimum distances. Larger withdrawal distances may be required, depending on the exact type and quantities of explosive weight. Refer to DOD Ammunition Explosive Safety Standards for the mathematical equation for figuring the exact distances, which may be larger than the minimum required distances. For bombs and projectiles with five-inch caliber or greater, use a minimum distance of 4,000 feet. Finally, the minimum withdrawal distance for a fire involving an explosive-laden facility of known contents and quantities placarded with fire symbol 1 is not less than 1,250 feet for bulk explosives and not less than 4,000 feet for fragmenting munitions. Again, these are only minimum distances and provide only limited protection, depending on the type and quantity of munitions involved.
Firefighting procedures depend on fire involvement of fire symbol 1 materials. When they are involved in fire and no rescue is required, do not fight the fire. Protect exposures and take suitable cover from the explosion. If the material is involved and rescue is needed, fight the fire and try to cool the involved munitions. After rescue has been completed, seek suitable cover. Cool munitions not yet involved but exposed to radiant heat with a water fog. Do not use foam, as it acts as an insulator of heat. Although the above is accepted policy for fire symbol 1 materials, duration of involvement plays a major role in the senior fire official’s decision to attempt rescue. The longer a munition is involved in fire, the more unstable it becomes. This in turn makes the decision to send firefighters into this situation a difficult one. Examples of this division are munitions with any amount of high explosives, such as the Air Intercept Missile, AIM-7 with warhead; the General Purpose Bomb, MK 84; and the Cluster Bomb Unit, CBU49B/A.
Class 1 Division 2 (1.2). Fire Symbol 2, like fire symbol 1, represents a blast hazard. With F/S 2 materials, however, the added hazard of fragmentation (the rapid release, or explosion, of hot metal pieces in all directions) also is present. The symbol used to indicate the presence of F/S 2 materials is an orange “X” with the black numeral 2 centered in it. Withdrawal distance for nonessential personnel is not less than 2,500 feet for an accident involving fire of an explosiveladen facility, a tractor trailer, a cargo truck, or a rail car of known content or quantity of fire symbol 2 material.
Firefighting procedures for fires involving F/S 2 materials and requiring a rescue arc as follows: Cool munitions, fight fire, attempt rescue, and seek suitable cover if necessary. If involved in a fire with no rescue required, the procedures are fight fire, withdraw if necessary, and be aware of the blast and/or fragmentation. Do not use foam, as it acts as an insulator of heat. Similar to F/S 1, F/S 2 materials become more unstable when exposed to fire for long periods of time. However, the blast hazard is not as severe, but fragmentation is an added problem. Here again, the senior fire official has to make a difficult decision. Examples of munitions in this category are hand grenades, claymore mines, and antipersonnel bomblets.
Class 1 Division 3 (1-3)- Mass fire is the hazard implied by a fire symbol 3 material. This type of munition is capable of producing massive amounts of intense fire. Ignition temperature of the material is relatively low, thus creating rapid spread when several like munitions are present. The shape used to show F/S 3 material is an inverted (upside down) triangle. The background color is orange, and the black numeral 3 appears in the triangle. This type of munition does not present as severe a hazard of blast or fragmentation as the two preceding divisions of munitions. The minimum withdrawal distance for this symbol is 600 feet for an accident involving fire of an explosive-laden tractor trailer, a cargo truck, a rail car, or a facility of known contents and quantities.
Firefighting procedure is to fight the fire. Be aware of rapid and massive fire spread and plan accordingly. Cool uninvolved munitions when possible. Foam is not acceptable with this group of munitions either. Examples of F/S 3 materials are napalm, a flammable gel; incendiary style munitions; white phosphorus; pyrotechnics; and magnesium incendiaries.
Class 1 Division 4 (1.4). This division generally is a catchall for all other conventional munitions that do not fall into the three preceding divisions. Fire symbol 4 materials represent a moderate fire hazard. This category’s symbol is an orange diamond with the black numeral 4. The minimum withdrawal distance for nonessential personnel is 300 feet for an accident involving fire of an explosive-laden tractor trailer, a cargo truck, a rail car, or a facility of known contents and quantities. Fight fires involving these types of munitions regardless of the extent of involvement.
Conventional munitions, Class 1 explosives, are placarded with one of the preceding symbols. Special, nuclear, or specific chemical agents have no marking system, and all information regarding them is classified and dispensed on a need-to-know basis.
CHEMICAL MUNITIONS
Chemical munitions have their own placarding symbols, which also fall under the general category of fire symbols. Chemical symbols do not use a numbering system. The DOT and UN, however, have assigned chemical munitions to Class 6.1, Poisonous and Irritating Materials, and 6.2, Etiological Agents (disease-producing chemicals). As a result of a 1970 presidential order, the military does not recognize Class 6 Division 2 offensive weapons. They, therefore, will not be dealt with in this section.
Chemical munition symbols use a combination of colors and figures to relay information. Information obtained from these symbols includes the type of chemical hazard and the protective clothing required. Protective clothing is referred to as “sets.” Sets 1, 2, and 3 are explained as they are encountered. The military designation for these sets is Class 6 division.
Set I Toxic Agents. These materials are known as casualty agents and are designed to kill. The symbol for this group of agents is a round placard with a blue background and a red oneinch rim and human silhouette in protective clothing. This sign is best known by the adage “Red is dead.”
This saying illustrates the potential hazard—death —if exposure occurs. Protective clothing required for this material is of a special nature; a few hazardous-materials chemical suits may work, depending on the exact type of agent. In military situations, the set 1 chemical warfare ensemble designed to protect personnel from toxic agent gas or vapor exposure would be used. It provides some protection against direct contact with liquid agents; however, protection time is only a few minutes after contact occurs. Set 1 consists of a gas mask, M-9 series, and an impermeable suit (coveralls, hood, gloves, firefighter boots, and boot covers). The chemical warfare ensemble with M17 gas mask may be substituted where liquid contact is highly improbable. These outfits are not suitable for firefighting purposes. Examples of toxic chemicals used are the nerve agents Tabun and Sarin, blister agents, mustard gases, and methyldichlorethane.
Set 2 Harassing Agents. This category contains agents designed to harass such as riot-control agents (tear gas). The symbol’s background is blue, and the rim and figure are yellow. The hazard is a temporary incapacitation caused by tearing eyes, coughing, and/or temporary loss of motor skills.
Protective clothing for these materials includes self-contained breathing apparatus, coveralls, protective gloves, and firefighting protective clothing and equipment. Examples of this type of chemical are tear gases such as chloroacetophenone, vomiting-causing agents such as diphenylchloroarsine, and some smoke-producing agents such as titanium and tetrachloride.
Set 3 Illuminating Devices. Illuminating devices constitute the bulk of set 3 materials. The symbol has a blue background with a white rim and figure. The hazards presented are blinding and difficulty in extinguishment because of intense heat, spontaneous ignition, and the ability of some of the agents to burn without oxygen present. Protective clothing for set 3 consists of flame-resistant coveralls, flameproof gloves, and SCBA (firefighting protective clothing and equipment may be used). Examples of this group are white phosphorus, triethyl-aluminum, and hexachloroethane.
Wear-Breathing-Apparatus Sym -hoi. The fourth symbol in the chemical munitions group is a special designator: It directs all personnel entering the area to wear breathing apparatus. (Self-contained breathing apparatus must be worn, and firefighting protective clothing and equipment may be worn.) The symbol has a blue background with a one-inch white rim. The figure in the center is a close-up of a human face wearing a filter-type mask (also white). This symbol may be used with a variety of materials or in combination with the other previously mentioned symbols.
Apply-No-Water Symbol. Also a special designator, this symbol directs firefighters to use water cautiously as an extinguishing agent. The hazard targeted by this sign is the materials’ water-reactive nature. When mixed with water, these materials may explode, burn intensely, or do anything in between. The symbol has a white background. A red diagonal line and circles arc superimposed over a black silhouette of a fire and a bucket of water. This symbol is displayed whenever a water-reactive material is present.
The ability to recognize and identify the types of munitions and their hazards may save your life should you be called for mutual aid to a military installation. You must use your knowledge and experience accurately when handling these emergencies. If you have a military installation in your district, contact the base fire chief to arrange for training on the various types of munitions housed at that installation.
