Chemicals Hazard Rating System
The National Fire Protection Association (NFPA) has developed a system for indicating the health, flammability, reactivity and special hazards for many common chemicals through use of the NFPA 704 Diamond.
| RATINGS | HEALTH | FLAMMABILITY | REACTIVITY | SPECIAL |
|---|---|---|---|---|
| 4 SEVERE | Deadly, even the slightest exposure to this substance would be life threatening. | Flash Point Below 73 F This substance is extremely flammable, volatile and explosive. | May Detonate Substances may explode at normal temperatures and pressures. | SPECIFIC HAZARD Radiation Acid alkali corrosive oxidizer use no water |
| 3 SERIOUS | Extreme Danger: serious injury would result from exposure to this substance. | Flash Point Below 100 F Flammable, volatile or explosive at normal temperatures and pressure. | Explosive Capable of detonation or explosion by heat, shock or water. | |
| 2 MODERATE | Dangerous: exposure to this substance would be hazardous to health. | Flash Point Below 200 F Moderately heated conditions may ignite this substance. | Unstable Violent chemicals changes are possible at normal temperatures or pressures or when mixed with water. | |
| 1 SLIGHT | Irritation or minor injury would result from exposure to this substance. | Flash Point Above 200 Substance must be preheated to ignite. | Normally Stable Substances which may become unstable at elevated temperatures or pressures or with water. | |
| O MINIMAL | No significant hazard or health risk. | Will Not Burn. | Stable Substances remain stable with heat, pressure and with water. |
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