Chemicals and Hazard Rating Systems

The National Fire Protection Association (NFPA) hazard system for chemical materials

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.