NFPA 704

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  An NFPA Diamond indicating that hazardous materials are stored in this building.

 

The NFPA 704 Diamond is a means of disseminating hazard information for a material. The diamond is divided into four sections. Each of the first three colored sections has a number in it associated with a particular hazard. The higher the number is, the more hazardous a material is for that characteristic. The fourth section includes special hazard information. Here are the four sections and an explanation of the numbers in them.

 

Red -- Flammability Hazard
Yellow -- Reactivity Hazard
     
4 - Materials with a flashpoint below 73°F and a boiling point above 100°F 4 - Material is capable of explosion or detonation at normal temperature and pressure
3 - Materials with a flashpoint below 73°F and a boiling point greater than or equal to100°F, or a flashpoint above 73°F and less than 100°F 3 - Material is capable of explosion, but requires a strong initiating source, or the material reacts explosively with water
2 - Materials with a flashpoint above 100°F, but not exceeding 200°F 2 - Material undergoes violent chemical changes at elevated temperature and pressure
1 - Materials with a flashpoint above 200°F 1 - Normally stable, but can become unstable at elevated temperatures
0 - Materials which normally won't burn 0-Normally stable
Blue -- Health Hazard
White -- Special Hazard
     
4 - Materials with an oral LD50 of less than or equal to 5 mg/kg

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Water Reactive

3 - Materials with an oral LD50 above 5, but less than 50 mg/kg

Oxidizer

2 - Materials with an oral LD50 above 50, but less than 500 mg/kg

Corrosive

1 - Materials with an oral LD50 above 500, but less than 2000 mg/kg

Radioactive

0 - Materials with an oral LD50 above 2000 mg/kg    


 

The NFPA Diamond was designed by the National Fire Protection Association and describes how a material will react in a fire more so than in normal chemical use. Often, the NFPA Diamond for a particular material will have numbers that are different than a HMIS or University of Memphis label.

The NFPA Diamond is required on buildings where certain quantities of hazardous materials are stored.