Danger Diamond

The danger diamond is a symbol that came to Europe from the United States.  It has been defined by the National Fire Protection Association. – NFPA (National Fire Protection Association) and is described by the NFPA 407 standard. This sign is mainly used by emergency services for quick identification of hazardous substances. The specific properties of the substance, the health hazards and the method of extinguishing a fire involving this substance. It consists of four colored fields with numbers from 0 to 4. The colors and numbers indicate, in order:

Blue field – health hazard

0. No health hazard in case of normal contact.
1. May cause temporary health problems.
2. Contact may cause temporary health problems with the risk of complications.
3. Brief contact may cause serious poisoning.
4. Very brief contact may cause death or serious poisoning.

Red field – fire hazard/flammability

0. Non-flammable substance.
1. The material must be heated to a high temperature to ignite. Ignition temperature above 93ºC.
2. The substance must be heated to ignite. Ignition temperature 38–93°C.
3. Liquids and solids that ignite at room temperature. Flash point 27–38°C.
4. The substance immediately disperses in the air, forming an explosive mixture.

Yellow field – instability/reactivity

0. Stable under normal conditions, does not react with water, is not affected by open flames.
1. Stable under normal conditions, but may become unstable under increased pressure or at higher temperatures.
2. It undergoes dangerous chemical changes at elevated temperatures and pressures, reacts with water, or produces explosive products as a result of reaction with water.
3. Capable of detonation or explosive decomposition under the influence of a strong stimulus, must be heated to initiate a reaction, reacts explosively with water, or explodes from shock.
4. A substance capable of detonating or decomposing vigorously under normal conditions of temperature and pressure.

White field – additional information

OXY or OX – Oxidizing agent.
W – Reacts vigorously when in contact with water. Often in an unpredictable manner. In case of fire, do not extinguish with water.
SA – Choking gas.
COR – Corrosive/caustic substance (acid or base).
CRIO or CRY – A cryogenic substance that produces low temperatures (e.g., dry ice).
BIO – Biological hazard.
POI – Poison.