Napalm can be extinguished, but doing so is extraordinarily difficult compared to putting out nearly any other fire. The combination of extreme heat, a sticky gel that clings to whatever it touches, and a fuel mixture designed to sustain prolonged burning means that conventional firefighting methods like spraying water largely fail. Understanding why requires looking at what napalm actually is, how it burns, and what fire suppression approaches have any real effect on it.
What Napalm Is and Why It Burns the Way It Does
Napalm is not a single chemical. It is a thickened fuel, essentially gasoline or a similar petroleum product mixed with a gelling agent that turns a liquid into a sticky, syrupy substance. The original formulation, developed during World War II, combined naphthenic acid and palmitic acid with gasoline, and the name “napalm” is a portmanteau of those two thickeners. The gelling agent serves a specific military purpose: it makes the fuel cling to surfaces instead of splashing off, and it slows the burn rate so the fire lasts longer.
The later and more widely known version, called Napalm-B, replaced the original acids with polystyrene dissolved in benzene, then mixed with gasoline. This created an even stickier, more tenacious gel that burned hotter and longer than its predecessor. Napalm-B burns at temperatures commonly cited around 800 to 1,200 degrees Celsius, depending on conditions, and can sustain burning for several minutes in a concentrated mass. That temperature range is hot enough to melt through sheet metal, ignite nearly anything organic on contact, and turn nearby water into steam almost instantly.
The gel consistency is central to why napalm fires behave so differently from a pool of burning gasoline. Liquid gasoline, if ignited on a flat surface, burns relatively quickly and can be smothered or displaced. Napalm, by contrast, sticks. It adheres to skin, clothing, vegetation, vehicles, and structures, and once it sticks, the fire goes where the gel goes. Researchers studying gel fuel burns have described this as the “napalm effect,” where the fuel continues to burn on whatever surface it has adhered to, producing deep and extensive injuries, particularly to the hands, face, and upper body.1Oxford Academic. Gel Fuel Burns and the Napalm Effect
Why Water Does Not Work
The instinct when facing any fire is to reach for water, and with napalm this instinct can actually make things worse. Several properties of napalm conspire against water-based suppression.
First, napalm is petroleum-based and hydrophobic. Like any oil or gasoline fire, water and napalm do not mix. Spraying water onto burning napalm causes the water to bead up and roll off the gel or flash into steam on contact with the superheated surface. The steam itself is dangerous, expanding rapidly and potentially scattering burning gel fragments over a wider area. This is the same reason you never throw water on a grease fire in a kitchen, but scaled up dramatically.
Second, the temperatures involved overwhelm what water can absorb. Water extinguishes fire primarily by cooling the burning material below its ignition point and by displacing oxygen as steam forms. But when the burning substance is at 1,000-plus degrees, the water evaporates so rapidly that it cannot maintain contact long enough to cool anything. The thermal mass of a napalm fire simply outpaces what water can accomplish.
Third, because napalm clings to surfaces, you cannot wash it away the way you might wash away a pool of burning liquid. The gel resists being displaced by water pressure. Hosing it down may spread it without extinguishing it, creating new fire surfaces rather than eliminating the original one.
What Can Actually Suppress a Napalm Fire
Extinguishing napalm is not impossible, but the methods that show any effectiveness work on different principles than water. The key is either smothering the fire by cutting off oxygen, or using chemical agents that interrupt the combustion reaction itself.
Sand, Dirt, and Physical Smothering
The simplest approach with any real track record is burying the burning napalm under a heavy, non-combustible material like sand or dirt. This works by physically blocking oxygen from reaching the flame. Unlike water, sand does not evaporate or splash away. It sits on the fire and, if applied in sufficient volume, can smother it. Military training manuals have long recommended this as a field expedient for napalm fires on equipment or in defensive positions. The obvious limitation is that you need a large quantity of sand or earth readily available, and you need to apply it quickly before the fire spreads. On a person, covering burning napalm with sand or dirt is painful and imprecise, but it remains one of the more effective options in the absence of specialized equipment.
Dry Chemical Extinguishers
Dry chemical fire extinguishers, the type that spray a fine powder (typically monoammonium phosphate or sodium bicarbonate), have been tested on napalm fires. The U.S. military and fire research agencies explored dry chemical agents as potential countermeasures for incendiary weapons as far back as the 1950s.2ACS Publications. SAFETY Dry chemicals work by interrupting the chemical chain reaction of combustion rather than by cooling. When the powder coats the burning surface, it interferes with the free radicals that sustain the flame. Against napalm, dry chemicals perform better than water but still face the challenge that the gel burns so hot and so persistently that the powder can be consumed or displaced before fully extinguishing the fire. For small napalm fires, a large dry chemical extinguisher can be effective. For large-scale napalm conflagrations, the quantity of agent required becomes impractical.
Foam
Firefighting foam, particularly the protein-based and synthetic foams designed for petroleum fires (known as Class B foams), works by forming a blanket over the fuel surface that suppresses vapor release and blocks oxygen. Foam is more effective against napalm than plain water because it stays in place rather than running off, and the blanket effect addresses the oxygen-deprivation side of fire suppression. Aqueous film-forming foam (AFFF) has been a standard tool for airport crash trucks and military fire departments partly because of its effectiveness against large petroleum-based fires. Against napalm specifically, foam can suppress the fire if applied in large volumes and maintained, but the extremely high temperatures can break down the foam blanket, requiring sustained application. It is a viable tool, not a magic solution.
The Oxygen Problem
One common misconception is that napalm “makes its own oxygen” and therefore cannot be smothered at all. This is not accurate. Napalm is not an oxidizer like thermite or solid rocket fuel. It requires atmospheric oxygen to burn, just like any petroleum fire. The confusion likely arises because napalm fires are so intense that they create strong convective currents, pulling in fresh air from the surrounding environment and making it appear as though the fire feeds itself. A napalm fire in a sealed container with no oxygen supply would eventually go out.
The practical problem is that in real-world conditions, you almost never encounter napalm in a sealed environment. On open ground, in buildings with openings, or on a person, there is always ambient air feeding the fire. And the intensity of the burn means it draws air in aggressively. So while napalm does not technically produce its own oxygen, the fire behaves in ways that make oxygen deprivation extremely difficult to achieve in practice without physically burying the fire under an inert material.
What Happens When Napalm Hits Skin
The burn injuries caused by napalm are among the most severe in combat medicine, and the difficulty of extinguishing napalm on a person’s body is a major reason why. When the gel contacts skin, it adheres immediately. Attempting to wipe it off with bare hands simply transfers the burning gel to the hands. Attempting to peel off clothing that has napalm on it can pull skin away with it, because the gel bonds to both fabric and tissue.
Clinical literature on gel fuel burns, which share key characteristics with napalm burns, confirms that these injuries tend to be deep, often full-thickness, and disproportionately affect the hands and face because people instinctively try to swat the fire or shield their face.1Oxford Academic. Gel Fuel Burns and the Napalm Effect The depth of injury is compounded by the fact that the gel keeps burning while in direct contact with tissue, producing sustained thermal damage that penetrates through the skin layers rapidly.
The standard advice for a person on fire, “stop, drop, and roll,” has limited effectiveness with napalm. Rolling can smother some of the flame by cutting off oxygen, but because the gel is sticky, it does not fall away from the body the way burning clothing might. The most effective immediate response, if nothing else is available, is to smother the burning area with a heavy blanket, coat, or tarp, or to use sand or dirt. Submerging in water can help cool the surrounding tissue and may reduce the fire, but as described above, water alone is not highly effective at extinguishing the gel itself.
How Napalm-B Changed the Problem
The shift from the original napalm formulation to Napalm-B in the mid-1960s made an already difficult fire even harder to fight. The polystyrene in Napalm-B serves a dual function: it thickens the fuel and it burns as a fuel itself. Polystyrene is a polymer that, when ignited, produces a hot, long-lasting flame and generates thick black smoke containing toxic compounds. This means Napalm-B has more total energy content per volume than the original mixture, burns at higher temperatures, and produces combustion byproducts that are themselves hazardous.
The inclusion of benzene as a solvent in the Napalm-B formula adds another layer of danger. Benzene is volatile, highly flammable, and a known carcinogen. When Napalm-B ignites, the benzene vaporizes rapidly, contributing to the initial flash and spread of the fire. For anyone attempting to extinguish a Napalm-B fire, the toxic smoke and benzene vapor create respiratory hazards that compound the thermal danger. This is one reason why military fire crews trained for napalm scenarios use self-contained breathing apparatus in addition to specialized extinguishing agents.
From a suppression standpoint, the polystyrene makes the gel even stickier and more resistant to displacement than the original naphthenic-palmitic acid formula. The higher energy density means suppression agents must absorb more heat to bring the fire under control. Every change that made Napalm-B more effective as a weapon simultaneously made it harder to extinguish.
Modern Research into Advanced Extinguishing Materials
While napalm itself is no longer widely used by most militaries (the United States, for instance, largely phased it out after the Vietnam War era, though incendiary munitions in general remain in some arsenals), the underlying challenge of extinguishing petroleum-based gel fires remains relevant. Industrial gel fuels, intentional arson accelerants, and wildfire situations involving petroleum products all pose similar suppression problems.
One promising area of research involves hydrogel-based extinguishing materials. These are water-rich gels, often made with natural polymers, that combine high water content with the ability to form a cohesive film over a burning surface. The appeal of hydrogel extinguishants is that they deliver water in a form that does not immediately run off or flash to steam. The gel film insulates the surface, blocks oxygen, and releases water gradually as it absorbs heat. Recent work has highlighted that natural polymer hydrogels with high water containment and strong film-forming properties show significant potential as clean, efficient fire suppression agents that could eventually replace some traditional products.3PubMed Central. Hydrogel Extinguishants
The principle is almost poetically appropriate: to fight a gel fire, you use a gel extinguisher. A hydrogel can match the adhesive, surface-coating properties of napalm while delivering the cooling and oxygen-blocking effects needed for suppression. This technology is still in active development and has not yet been widely deployed specifically against napalm-type fires, but the underlying physics make it one of the more theoretically sound approaches to the problem.
The Legal and Practical Context
Protocol III of the United Nations Convention on Certain Conventional Weapons, adopted in 1980, restricts the use of incendiary weapons against civilian populations and against military targets located within concentrations of civilians. The protocol does not ban napalm or similar weapons outright in all contexts, but it places significant legal constraints on their use. The United States signed the convention but did not ratify Protocol III until 2009, and even then with reservations.
In practice, the difficulty of extinguishing napalm was one of the factors that drove international outrage and eventual regulation. The iconic photographs from the Vietnam War, showing burn victims and devastated landscapes, catalyzed public opposition not just because napalm was destructive but because its effects were so uniquely hard to stop once initiated. A conventional explosive destroys in an instant. Napalm destroys over minutes, and the people it contacts cannot put it out. That sustained, inescapable quality is what made it particularly horrifying and what eventually contributed to its diplomatic stigma.
Despite the legal restrictions, incendiary weapons have not disappeared from warfare. Thermobaric weapons, white phosphorus munitions, and various improvised incendiary devices continue to appear in conflicts around the world. Many of these share some of napalm’s fire-suppression challenges, particularly the combination of extreme heat, adhesive or dispersive characteristics, and toxic combustion products. The science of extinguishing napalm is therefore not purely historical. It informs how fire services, military engineers, and humanitarian organizations prepare for and respond to incendiary events today.
Common Myths About Napalm Fires
Popular culture and wartime folklore have generated several persistent myths about napalm that are worth addressing directly.
- Napalm burns underwater: It does not. Napalm requires atmospheric oxygen, and submerging burning napalm in water will eventually extinguish it. The myth likely comes from the fact that napalm on the water’s surface can float and burn, because the gel is less dense than water and remains exposed to air. But fully submerged, it goes out.
- Nothing can put out napalm: As covered throughout this article, several agents can suppress napalm fires. The difficulty is extreme, but “nothing works” is an overstatement. Foam, dry chemicals, sand, and emerging hydrogel technologies all have measurable effectiveness.
- Napalm is illegal everywhere: It is restricted under Protocol III of the CCW, but not universally banned. The restrictions apply to use against civilians and civilian areas, and some nations have not ratified the protocol at all.
- You can make napalm easily at home: Recipes circulate online, often involving polystyrene dissolved in gasoline. While this does produce a crude sticky flammable gel, it lacks the precise formulation, ignition characteristics, and dispersal mechanism of military napalm. It is also illegal to manufacture or possess incendiary weapons in most jurisdictions, and the process itself is extremely dangerous due to the volatile solvents involved.
Why Civilian Gel Fuel Fires Mirror the Problem
You do not need to be near a battlefield to encounter the fire-suppression challenges that napalm presents. Commercial gel fuels, used in decorative fireplaces, fondue sets, and catering chafing dishes, are composed of flammable alcohols like ethanol and methanol in a gelled form. When these products spill and ignite, they exhibit the same “napalm effect” described in burn literature: the gel adheres to skin and surfaces, sustains a burn, and resists conventional extinguishing attempts like splashing with water.1Oxford Academic. Gel Fuel Burns and the Napalm Effect
Gel fuel burns, while less severe in temperature than military napalm, still produce serious injuries. The burn patterns are similar because the underlying physics are the same: a thickened fuel that sticks and keeps burning. For household gel fuel fires, a Class B fire extinguisher (rated for flammable liquids) is the correct tool. Smothering with a lid or metal tray is effective for contained spills. Water should be avoided on the gel fire itself, though it can be used to cool surrounding skin or objects after the fire is out. The lesson from napalm science scales down to the kitchen: when fuel is gelled, the rules of fire suppression change, and grabbing water first can make the situation worse.