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Incendiary Agents and Hydrogen Fluoride (HF)


James M. Madsen

, MD, MPH, U.S. Army Medical Research Institute of Chemical Defense (USAMRICD)

Last full review/revision Feb 2021| Content last modified Feb 2021

There are many types of chemical-warfare agents that affect different parts of the body. Military incendiary agents are chemicals that are designed to illuminate the battlefield, to start fires, and to create smoke to obscure terrain and personnel. Agents include thickened gasoline (napalm), thermite, white phosphorus, and magnesium. Any of these compounds can cause mass casualties.

Napalm has a jelly-like consistency. The other incendiary agents are usually weaponized as powdered solids. Many incendiary agents are used in exploding projectiles or bombs. White phosphorus may continue to burn on skin or clothing as long as it is exposed to air. Because magnesium can burn under water, it will continue to burn within tissue.

Hydrofluoric acid (HF), used in industry and in other commercial applications, is often confused with hydrochloric acid (the acid used in swimming pools). For this reason, it is referred to as HF. HF can exist at room temperatures as a liquid or a vapor. The most common routes of exposure are through the skin, eyes, and lungs. HF penetrates deeply through the skin. In addition to causing severe burns and pain, HF can cause a serious imbalance of body chemicals (electrolytes) that sometimes causes an abnormal heart rhythm and death.


Burns caused by an incendiary agent are similar to those of other burns caused by heat or fire.

HF exposure may not cause pain or visible burns right away. Pain may appear within an hour but typically occurs only after 2 or 3 hours. However, once pain occurs, it is often deep and intense. Affected skin gradually becomes reddened but does not appear as severely affected as the intense pain would suggest.


  • A doctor's evaluation

Burns from an incendiary agent are readily apparent to first responders. However, because burns caused by HF (particularly in low concentrations) take time to cause symptoms, medical personnel remain vigilant for injury done to the person's deep tissues and organs. Burns caused by white phosphorus may glow or smoke when exposed to air.


  • Decontamination of the skin

First responders flood areas of skin affected by white phosphorus with water, or they smother the areas to block exposure to air. Particles of white phosphorus are removed (they often adhere tightly to skin) and placed in water. Smoking trails may be good indicators of the location of small particles. Particles of burning or smoking magnesium in the skin are removed as quickly as possible. Wounds can be covered with oil until particles can be removed.

For HF exposure, prompt decontamination is needed. Burns are flushed with lots of water. However, because HF penetrates the skin quickly, significant problems may occur even after thorough decontamination. Doctors usually apply a paste containing calcium or inject calcium into the exposed area. People with significant exposure are hospitalized to undergo cardiac monitoring and additional treatment.

The views expressed in this article are those of the author and do not reflect the official policy of the Department of Army, Department of Defense, or the U.S. Government.

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