main ways: burn injuries and vapour inhalation. Burning In munitions, white phosphorus burns readily with flames of 800 °C (1,472 °F). Incandescent particles from weapons using powdered white phosphorus as their payload produce extensive partial- and full-thickness burns, as will any attempt to handle burning submunitions without protective equipment. Phosphorus burns carry an increased risk of mortality due to the absorption of phosphorus into the body through the burned area with prolonged contact, which can result in liver, heart and kidney damage, and in some cases multiple organ failure. White phosphorus particles continue to burn until completely consumed or starved of oxygen. In the case of weapons using felt-impregnated submunitions, incomplete combustion may occur resulting in up to 15% of the WP content remaining unburned. Such submunitions can prove hazardous as they are capable of spontaneous re-ignition if crushed by personnel or vehicles. In some cases, injury is limited to areas of exposed skin because the smaller WP particles do not burn completely through personal clothing before being consumed. Due to the pyrophoric nature of WP, penetrating injuries are immediately treated by smothering the wound using water, damp cloth or mud, isolating it from oxygen until fragments can be removed: military forces will typically do so using a bayonet or knife where able. Bicarbonate solution is applied to the wound to neutralise any build-up of phosphoric acid, followed by removal of any remaining visible fragments: these are easily observed as they are luminescent in dark surroundings. Surgical debridement around the wound is used to avoid fragments too small to detect causing later systemic failure, with further treatment proceeding as with a thermal burn. Smoke inhalation Burning white phosphorus produces a hot, dense, white smoke consisting mostly of phosphorus pentoxide in aerosol form. Field concentrations are usually harmless, but at high concentrations the smoke can cause temporary irritation to the eyes, mucous membranes of the nose, and respiratory tract. The smoke is more dangerous in enclosed spaces, where it can cause asphyxiation and permanent respiratory damage. The US Agency for Toxic Substances and Disease Registry has set an acute inhalation Minimum Risk Level (MRL) for white phosphorus smoke of 0.02 mg/m3, the same as fuel-oil fumes. By contrast, the chemical weapon mustard gas is 30 times more potent: 0.0007 mg/m3. The agency cautioned that studies used to determine the MRL were based on extrapolations from animal testing and may not accurately