NFPA Hazard Rating System

Methodist University’s laboratory doors are posted with emergency information to warn occupants and The Fayetteville Fire Department personnel of the presence and identification of hazardous materials inside each laboratory. 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. The hazard rating for the laboratory is determined by looking at all the chemicals, gases and special lab uses in the laboratory and coming up with a rating for each hazard category based on criteria established below.

Please read the rating information in each category, take an inventory of your laboratory and rate each category accordingly. To look up a rating for a particular chemical click on the link at the bottom of the page. If you do not find the chemical listed, a review of the chemicals SDS sheet may help you rate the chemical in question. To look up a chemical’s SDS, click on SDS Database from an on-campus computer.

If there are any questions regarding a chemical rating, please either email your question or call the Office of Environmental Health and Safety at 910.630.7558.

Rating Summary

Health (Blue)

Use the most severe rating code regardless of volume.

  • 4 Danger May be fatal on short exposure. Specialized protective equipment required
  • 3 Warning Corrosive or toxic. Avoid skin contact or inhalation
  • 2 Warning May be harmful if inhaled or absorbed
  • 1 Caution May be irritating
  • 0 No unusual hazard

Flammability (Red)

The greatest volume of one code determines the marking. The only exception is if a more severe code has a volume of 3 gallons or greater, then that code is used instead of a lower code of greater volume. If the laboratory total volume of flammables or combustibles is less than one pint for all, then the rating for the laboratory for this area shall be zero.

  • 4 Danger Flammable gas or extremely flammable liquid
  • 3 Warning Flammable liquid flash point below 100°F
  • 2 Caution Combustible liquid flash point of 100° to 200°F
  • 1 Combustible if heated
  • 0 Not combustible

Reactivity (Yellow)

Use the most severe rating code regardless of volume.

  • 4 Danger Explosive material at room temperature
  • 3 Danger May be explosive if shocked, heated under confinement or mixed with water
  • 2 Warning Unstable or may react violently if mixed with water
  • 1 Caution May react if heated or mixed with water but not violently
  • 0 Stable Not reactive when mixed with water

Special Information (White)

Indicate the presence of the following regardless of volume.

  • Oxy Oxidizing Agent
  • W Water Reactive
  • G Compressed Gas
  • LN2 Liquid Nitrogen
  • LHE Liquid Helium

Special Signage Key

These are signs that shall or must be posted in addition to the NFPA diamond.

  • LAS Laser
  • BL Biosafety Level
  • RAD Radioactive Material
  • MAG Magnetic Fields
  • HVO High Voltage