NFPA 704 Facts for Kids

NFPA 704, often called a fire diamond, is a special sign shaped like a diamond. It helps people quickly understand the dangers of a chemical compound. This sign was created in 1960 by the National Fire Protection Association. It was designed to quickly tell firefighters and other emergency workers about nearby dangers.

The sign has four smaller diamonds inside it. There's a red one at the top, a yellow one on the right, a white one at the bottom, and a blue one on the left. Numbers or symbols inside these diamonds show how dangerous the chemical is.

The red diamond shows how easily a chemical can catch fire. This is called its flammability. The yellow diamond talks about reactivity. This means how quickly a chemical reacts with other materials. For example, some chemicals, like ammonium nitrate, can explode if they touch water. This is a type of reactivity. The blue diamond tells how dangerous the chemical is to a person's health. Each of these three diamonds (red, yellow, and blue) gets a score from 0 to 4. A score of 0 means there is no danger. A score of 4 means the danger is very high.

The white diamond has special codes for "special hazards." For example, if a chemical like ammonium nitrate should not touch water because it will explode, a W with a line through it will be in the white diamond.

Understanding the Codes
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Understanding the Codes

Flammability (Red Diamond)

This section tells you how easily a chemical can catch fire.

Flammability (red)
0	This chemical will not burn at all. Examples include carbon tetrachloride, concrete, stone, and sand.
1	This chemical needs a lot of heat for a long time before it will burn. It won't catch fire until it's heated to at least 93.3 °C (200 °F). An example is cooking oil.
2	This chemical needs pretty high temperatures to catch fire. It will catch fire at temperatures between 37.8 and 93.3 °C (100 and 200 °F). Diesel fuel is an example.
3	This chemical can catch fire at almost any temperature. Examples are gasoline and acetone.
4	This chemical can catch fire in the air at normal room temperatures. It burns very easily. These chemicals catch fire below 22.8 °C (73 °F). Examples include acetylene, propane, and liquid hydrogen.

Health (Blue Diamond)

This section tells you how dangerous a chemical is to your health.

Health (blue)
0	This chemical is not dangerous to anyone's health. You don't need any special protection. Examples are water, wood, and paper.
1	If you are exposed to this chemical, it might cause minor pain or injury. Examples include acetone and sodium chloride (salt).
2	This chemical could hurt a person if they are exposed to a lot of it at once, or a little bit of it for a long time. An example is hydrogen peroxide.
3	This chemical is toxic. Breathing it in, touching it, or getting it on your skin could cause serious injury. Examples are chlorine, liquid hydrogen, and carbon monoxide.
4	This chemical is very toxic. Even a very small amount of exposure could kill a person or hurt them very badly. Examples include cyanide and phosgene.

Reactivity (Yellow Diamond)

This section tells you how unstable or reactive a chemical is.

Instability/reactivity (yellow)
0	This chemical is very stable, even during fires. It does not react with water. An example is helium.
1	This chemical is usually stable, but it can become unstable at very high temperatures. An example is magnesium.
2	This chemical can react strongly with water, or it can form explosive mixtures with water. Examples include white phosphorus, potassium, and sodium.
3	This chemical can explode if it's heated or shocked. It might also explode when it touches water. An example is ammonium nitrate.
4	This chemical can spontaneously explode at normal temperatures. An example is nitroglycerin.

Special Hazards (White Diamond)

The white diamond shows special dangers. There are three official symbols for this section.

Special notice (white)
The white "special notice" area can contain several symbols. There are only three official symbols that can go in this section.
OX	This means the material is an oxidizer. It helps other chemicals burn even without air. Examples are ammonium nitrate and hydrogen peroxide.
₩	This means the chemical reacts with water in a strange or dangerous way. This chemical should not touch water. Examples include sodium and sulfuric acid.
SA	This means the chemical is a simple asphyxiant gas. It lowers the amount of oxygen in the air. This symbol is only used for gases like nitrogen, helium, neon, argon, krypton, or xenon.

Unofficial Symbols

Sometimes, other codes are put in the white triangle. These are not official NFPA codes, but you might still see them.

Non-standard symbols (white)
Sometimes, other codes are put in the white triangle. These are not official NFPA codes.
COR	This means the chemical is corrosive. It can burn through things. An example is sulfuric acid.
BIO or	This means there is a Biological hazard. It's a living thing, like a virus, that is dangerous. Examples include the flu virus and rabies virus.
POI	This means the chemical is Poisonous. An example is strychnine.
RA, RAD or	This means the chemical is radioactive. An example is plutonium.
CRY or CRYO	This means the chemical is cryogenic. These chemicals create very low temperatures that can injure people. An example is liquid nitrogen.