White phosphorus (weapon)

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This article is about the military applications of white phosphorus. For more general information, see Phosphorus.

White phosphorus is a common allotrope of the chemical element phosphorus which has found extensive military application as an incendiary agent ^[1], smoke-screening agent, and as an antipersonnel flame compound capable of causing serious burns^[2]. White Phosphorus (WP) bombs and shells are essentially incendiary devices, and can be used in an offensive anti-personnel role against enemy troop concentrations. It is used in bombs, artillery shells, and mortar shells which burst into burning flakes of phosphorus upon impact. White phosphorus has been described as a chemical weapon, but it has a long history of use in warfare for both offensive and target-marking purposes. It is commonly referred to in military jargon as "WP". The Vietnam War era slang "Willy(ie) Pete" or "Willy(ie) Peter" is still occasionally heard.

Contents 1 History 2 Applications 2.1 Smoke-screening agent 3 Effects on humans 3.1 Effects of exposure to WP weapons 3.2 Exposure and inhalation of smoke 3.3 Oral ingestion 4 Arms control status 4.1 Military regulations 4.2 Disposal at sea 4.3 Use in Iraq 4.4 Use in Lebanon by Israel 5 See also 6 External links 7 Notes

[edit] History

WP is believed to have been first used by Fenian arsonists in the 19th century in the form of a solution of WP in carbon disulfide. When the carbon disulfide evaporated, the WP would burst into flames, and probably also ignite the highly flammable carbon disulfide fumes. This mixture was known as "Fenian fire" and allegedly was also used by I.W.W. activists in the early 20th century.

Britain's army introduced its first factory-built WP grenades in late 1916. In World War II, white phosphorus mortar bombs, shells, rockets and grenades were used extensively by American, Commonwealth, and to a lesser extent Japanese forces, in both smoke-generating and antipersonnel roles. In 1940, when the invasion of Britain seemed imminent, the phosphorus firm of Albright and Wilson suggested that the British government use a material similar to Fenian fire in several expedient incendiary weapons. The only one fielded was the Grenade, No. 76 or Special Incendiary Phosphorus grenade, which consisted of a glass bottle filled with a mixture similar to Fenian fire, plus some latex (c.f. Molotov cocktail, Greek fire). It came in two versions, one with a red cap intended to be thrown by hand, and a slightly stronger bottle with a green cap, intended to be launched from the Northover projector (a crude 2.5 inch blackpowder grenade launcher). Instructions on each crate of SIP grenades included the observations, inter alia:

Store bombs (preferably in cases) in cool places, under water if possible.

Stringent precautions must be taken to avoid cracking bombs during handling.

It was generally regarded as overly dangerous to its own operators.

At the start of the Normandy campaign, 20% of American 81mm mortar rounds were WP. At least five American Medal of Honor citations mention their recipients using white phosphorus grenades to clear enemy positions. In the 1944 liberation of Cherbourg alone, a single U.S. mortar battalion, the 87th, fired 11,899 white phosphorus rounds into the city.

The U.S. Army and Marines used WP extensively in WWII and later in Korea, frequently using WP shells in large 4.2-inch chemical mortars. WP was widely credited by many Allied soldiers for breaking up numerous Nazi infantry attacks and creating havoc among enemy troop concentrations during the latter part of WWII. The psychological impact of WP on the enemy was noted by many troop commanders in WWII, and captured 4.2-inch mortarmen were sometimes summarily executed by German forces in reprisal. In both WWII and Korea, WP was found particularly useful in overcoming enemy 'human wave' attacks.

WP munitions were also used extensively in the Korean War and again in Vietnam. According to GlobalSecurity.org, "In the December 1994 battle for Grozny in Chechnya, every fourth or fifth Russian artillery or mortar round fired was a smoke or white phosphorus round." After claims by foreign news media that Israel used WP against Hezbollah targets during the Lebanon war, the Israeli government first issued denials. ^[3][4][5] Now, it acknowledges that its forces used white phosphorus during the 2006 Israel-Lebanon conflict.

Since white phosphorus can be used as a multi-purpose device to mark targets, provide a smoke screen, or signal to friendly troops, it is not covered by UN protocols on incendiary weapons when used in this fashion. In recent years, employment of WP weapons has declined with the increased effectiveness of modern proximity-fused anti-personnel and anti-armor fragmentation shells, bomblets, and missiles.

During WW II, incendiary bombs were used extensively by the German, British and US Air Forces against civilian populations, including against targets of military significance in civilian areas (Hamburg, Dresden, Area bombing etc). Late in the war, some of these bombs used white phosphorus (about 1-200 grams) in place of magnesium as the igniter for their flammable mixtures. The use of incendiary weapons against civilians was eventually banned (by signatory countries) in the 1980 United Nations Convention on Certain Conventional Weapons Protocol III. The USA has signed Articles I and II, but was not a signatory to Protocols III, IV, and V.

[edit] Applications

[edit] Smoke-screening agent

Weight-for-weight, phosphorus is the most effective smoke-screening agent known, for two reasons:

1. It absorbs most of the screening mass from the surrounding atmosphere; and
2. The smoke particles are actually an aerosol, a mist of liquid droplets which are close to the ideal range of sizes for Mie scattering of visible light. This effect has been likened to three dimensional textured privacy glass—the smoke cloud does not obstruct an image, but thoroughly scrambles it. It also absorbs infrared radiation.

When phosphorus burns in air, it first forms phosphorus pentoxide (which exists as tetraphosphorus decoxide except at very high temperatures):

P₄ + 5 O₂ → P₄O₁₀

However phosphorus pentoxide is extremely hygroscopic and quickly absorbs even minute traces of moisture to form liquid droplets of phosphoric acid:

P₄O₁₀ + 6 H₂O → 4 H₃PO₄ (also forms polyphosphoric acids such as pyrophosphoric acid, H₄P₂O₇)

Since an atom of phosphorus has an atomic mass of 31 but a molecule of phosphoric acid has a molecular mass of 98, the cloud is already 68% by mass derived from the atmosphere (i.e. you have 3.2 kilograms of smoke for every kilogram of WP you started with); however, it may absorb more because phosphoric acid and its variants are hygroscopic. Given time, the droplets will continue to absorb more water, growing larger and more dilute until they reach equilibrium with the local water vapour pressure. In practice, the droplets quickly reach a range of sizes suitable for scattering visible light and then start to dissipate from wind or convection.

Because of the great weight efficiency of WP smoke, it is particularly suited for applications where weight is highly restricted, such as hand grenades and mortar bombs. An additional advantage for hand smoke grenades—which are more likely to be used in an emergency—is that the WP smoke clouds form in a fraction of a second. Because WP is also pyrophoric, most munitions of this type have a simple burster charge to split open the casing and spray fragments of WP through the air, where they ignite spontaneously and leave a trail of rapidly thickening smoke behind each particle. The appearance of this cloud forming is easily recognised; one sees a shower of burning particles spraying outward, followed closely by distinctive streamers of white smoke, which rapidly coalesce into a fluffy, very pure white cloud (unless illuminated by a coloured light source).

Various disadvantages of WP are discussed below, but one which is particular to smoke-screening is "pillaring". Because the WP smoke is formed from fairly hot combustion, the gasses in the cloud are hot, and tend to rise. Consequently the smoke screen tends to rise off the ground relatively quickly and form aerial "pillars" of smoke which are of little use for screening. Tactically this may be counteracted by using WP to get a screen quickly, but then following up with emission type screening agents for a more persistent screen. Some countries have begun using red phosphorus instead. Red phosphorus ("RP") burns cooler than WP and eliminates a few other disadvantages as well, but offers exactly the same weight efficiency. Other approaches include WP soaked felt pads (which also burn more slowly, and pose a reduced risk of incendiarism) and PWP, or plasticised white phosphorus.

[edit] Effects on humans

White phosphorus can cause injuries and death in three ways: by burning deep into soft tissue, by being inhaled as a smoke and by being ingested. Extensive exposure in any way can be fatal.

[edit] Effects of exposure to WP weapons

Incandescent particles of WP cast off by a WP weapon's initial explosion can produce extensive, deep (second and third degree), painful burns. Phosphorus burns carry a greater risk of mortality than other forms of burns due to the absorption of phosphorus into the body through the burned area, resulting in liver, heart and kidney damage, and in some cases multi-organ failure.^[6] These weapons are particularly dangerous to exposed people because white phosphorus continues to burn unless deprived of oxygen or until it is completely consumed, in some cases burning right down to the bone. In some cases, burns may be limited to areas of exposed skin because the smaller WP particles do not burn completely through personal clothing before being consumed. According to GlobalSecurity.org, quoted by "The Guardian", "White phosphorus results in painful chemical burn injuries" ^[7] .

[edit] Exposure and inhalation of smoke

Burning WP produces a hot, dense white smoke. Most forms of smoke are not hazardous in the kinds of concentrations produced by a battlefield smoke shell. However, exposure to heavy smoke concentrations of any kind for an extended period (particularly if near the source of emission) does have the potential to cause illness or even death.

WP smoke irritates the eyes and nose in moderate concentrations. With intense exposures, a very explosive cough may occur. However, no recorded casualties from the effects of WP smoke alone have occurred in combat operations and to date there are no confirmed deaths resulting from exposure to phosphorus smokes. ^[7] The Agency for Toxic Substances and Disease Registry has set an acute inhalation Minimum Risk Level (MRL) for white phosphorus smoke of 0.02mg/m³, the same as fuel oil fumes. (By contrast, the chemical weapon mustard gas is 30 times more potent: 0.0007 mg/m³.) ^[8]

[edit] Oral ingestion

The accepted lethal dose when white phosphorus is ingested orally is 1 mg/kg, although the ingestion of as little as 15 mg has resulted in death. It may also cause liver, heart or kidney damage. ^{[9] [10]} There are reports of individuals with a history of oral ingestion who have passed phosphorus-laden stool ("smoking stool syndrome"). ^[11]

[edit] Arms control status

Protocol III of the Convention on Certain Conventional Weapons prohibits the use of incendiary weapons against civilians or in civilian areas. However, the use against military targets outside civilian areas is not explicitly banned by any treaty. There is a debate on whether white phosphorus should be considered a chemical weapon and thus be outlawed by the Chemical Weapons Convention (CWC) which went into effect in April of 1997. The convention is meant to prohibit weapons that are "dependent on the use of the toxic properties of chemicals as a method of warfare" (Article II, Definitions, 9, "Purposes not Prohibited" c.). The convention defines a "toxic chemical" as a chemical "which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals".(CWC, II). Because its effects are physical and not chemical, WP was not included in the CWC's original annex listing chemicals that fell under this definition for purposes of verification.^[12] However, some opponents have argued that white phosphorus interactions with human physiology could still provide a basis for its prohibition under the CWC.^[13]

In 2005, interviewed by the RAI, Peter Kaiser, spokesman for the Organisation for the Prohibition of Chemical Weapons (which is not associated with the UN), which oversees the CWC, publicly questioned whether the weapon should fall under the convention's provisions: "No it's not forbidden by the CWC if it is used within the context of a military application which does not require or does not intend to use the toxic properties of white phosphorus. White phosphorus is normally used to produce smoke, to camouflage movement. If that is the purpose for which the white phosphorus is used, then that is considered under the convention legitimate use. If on the other hand the toxic properties of white phosphorus are specifically intended to be used as a weapon, that of course is prohibited, because the way the convention is structured or the way it is in fact applied, any chemicals used against humans or animals that cause harm or death through the toxic properties of the chemical are considered chemical weapons." ^[14]. Despite Kaiser's assertion, the United States has not acquiesced to this view of the Convention, and is not bound by such assertions.

Some opponents have also argued that because of its incendiary effects, WP is potentially restricted by the 1980 Convention on Conventional Weapons (Protocol III), which prohibits the use of air-delivered incendiary weapons against civilian populations or indiscriminate incendiary attacks against military forces co-located with civilians. ^[15] However, that protocol also specifically excludes weapons whose incendiary effects are secondary, such as smoke grenades. This has been often read as excluding white phosphorus munitions from this protocol, as well. In any case, the third protocol has not been signed by the United States.^[16]

[edit] Military regulations

According to the US Army field manual on the Rule of Land Warfare, "The use of weapons which employ fire, such as tracer ammunition, flamethrowers, napalm and other incendiary agents, against targets requiring their use is not violative of international law." ^[17] However, there is some conflicting guidance given by the US Command and General Staff College at Fort Leavenworth. ST 100-3 Battle Book, a student text, states that "It is against the law of land warfare to employ WP against personnel targets." ^[18] This seems at odds with other field manuals which discuss the use of white phosphorus against personnel.^[19]

[edit] Disposal at sea

Following World War II, the United States disposed of tons of white phosphorus munitions by dumping them into the ocean. In 1989, the Army Chemical Materials Agency prepared a report entitled Summary of Some Chemical Munitions Sea Dumps by the United States which detailed the history of dumping incidents for weapons that included mustard gas, lewisite, cyanide and white phosphorus.^{[citation needed]} In 2001, another report, entitled Offshore disposal of chemical agents and weapons conducted by the United States, corroborated the dumping.^{[citation needed]} Other countries have also dumped white phosphorus at sea.^{[citation needed]}

[edit] Use in Iraq

Main article: White phosphorus use in Iraq

The United States Army has acknowledged using these bombs in the Iraq War in areas such as Fallujah. ^[20] On November 15, 2005, Dept. of Defense spokesman Lieutenant-Colonel Barry Venable confirmed to the BBC that WP had been used as an antipersonnel weapon in Fallujah:^[21]

Yes, it was used as an incendiary weapon against enemy combatants. When you have enemy forces that are in covered positions that your high explosive artillery rounds are not having an impact on and you wish to get them out of those positions, one technique is to fire a white phosphorus round into the position because the combined effects of the fire and smoke - and in some case the terror brought about by the explosion on the ground - will drive them out of the holes so that you can kill them with high explosives.

—Lieutenant-Colonel Barry Venable, Dept. of Defense spokesman

On November 30, 2005, General Peter Pace defended use of WP, declaring that WP munitions were a "legitimate tool of the military", used to illuminate targets and create smokescreens, adding: "It is not a chemical weapon. It is an incendiary. And it is well within the law of war to use those weapons as they're being used, for marking and for screening". Peter Pace argued that conventional weapons can be more dangerous than non-conventional weapons: "A bullet goes through skin even faster than white phosphorus does".^[22]

[edit] Use in Lebanon by Israel

During the 2006 Israel-Lebanon conflict, Israel used phosphorus shells against alleged Hezbollah targets in south Lebanon.[1] Israel stated that its use of the chemical was permitted under international conventions.^[23] President of Lebanon Émile Lahoud claimed that phosphorus shells were used against civilians in Lebanon. Several media sources had reported they had seen Lebanese civilians with injuries characteristic of phosphorus.^[24]

[edit] See also

• White phosphorus chemical
• Mark 77 bomb
• Fallujah, The Hidden Massacre

[edit] External links

• Globalsecurity.org on WP (including use during the Battle of Fallujah and during the December 1994 battle for Grozny during the First Chechen War)
• TF 2-2 IN FSE AAR: Indirect Fires in the Battle of Fallujah (PDF) Field Artillery Magazine (March-April 2005)
• "US 'uses incendiary arms' in Iraq", BBC, November 8, 2005.
• December 9, 2004 U.S. Denial of Using Illegal Weapons in Fallujah AND November 10, 2005 note - following RAI doc - recognizing WP use for screening purposes and as a "potent psychological weapons" in "shake&bake" operations
• "The fog of war: white phosphorus, Fallujah and some burning questions (by Andrew Buncombe and Solomon Hughes)", The Independent, November 15, 2005.
• "US used white phosphorus in Iraq (Lt Col Barry Venable)", BBC, November 16, 2005.
• "U.S. official admits phosphorus used as weapon in Iraq", CBC, November 16, 2005.
• "Incendiary weapons: The big white lie", The Independent, November 17, 2005.
• "US general defends phosphorus use", BBC, November 30, 2005.
• White phosphorus chemical backgrounder

[edit] Notes