Science, Tech, Math › Science What Is NFPA 704 or the Fire Diamond? Share Flipboard Email Print This is an example of a NFPA 704 warning sign. The four colored quadrants of the sign indicate the types of hazards presented by a material. This is the NFPA 704 for sodium borohydride. public domain Science Chemistry Abbreviations & Acronyms Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated July 23, 2018 You probably have seen NFPA 704 or the fire diamond on chemical containers. The National Fire Protection Association (NFPA) in the United States uses a standard called NFPA 704 as a chemical hazard label. NFPA 704 sometimes is called a "fire diamond" because the diamond-shaped sign indicates flammability of a substance and also communicates essential information about how emergency response teams should deal with a material if there is a spill, fire or other accident. Understanding the Fire Diamond There are four colored sections on the diamond. Each section is labeled with a number from 0-4 to indicate the level of hazard. On this scale, 0 indicates "no hazard" while 4 means "severe hazard". The red section indicates flammability. The blue section indicates a health risk. Yellow indicates reactivity or explosivity. The white is section is used to describe any special hazards. Hazard Symbols on NFPA 704 Symbol and Number Meaning Example Blue - 0 Does not pose a health hazard. No precautions are necessary. water Blue - 1 Exposure may cause irritation and minor residual injury. acetone Blue - 2 Intense or continued non-chronic exposure may result in incapacitation or residual injury. ethyl ether Blue - 3 Brief exposure may cause serious temporary or moderate residual injury. chlorine gas Blue - 4 Very brief exposure may cause death or major residual injury. sarin, carbon monoxide Red - 0 Will not burn. carbon dioxide Red - 1 Must be heated in order to ignite. Flashpoint exceeds 90°C or 200°F mineral oil Red - 2 Moderate heat or relatively high ambient temperature is required for ignition. Flashpoint between 38°C or 100°F and 93°C or 200°F diesel fuel Red - 3 Liquids or solids that readily ignite at most ambient temperature conditions. Liquids have a flash point below 23°C (73°F) and the boiling point at or above 38°C (100°F) or flash point between 23°C (73°F) and 38°C (100°F) gasoline Red - 4 Rapidly or completely vaporizes at normal temperature and pressure or readily disperses in air and readily burns. Flashpoint below 23°C (73°F) hydrogen, propane Yellow - 0 Normally stable even when exposed to fire; not reactive with water. helium Yellow - 1 Normally stable, but may become unstable elevated temperature and pressure. propene Yellow - 2 Changes violently at elevated temperature and pressure or reacts violently with water or forms explosive mixtures with water. sodium, phosphorus Yellow - 3 May detonate or undergo explosive decomposition under the action of a strong initiator or reacts explosively with water or detonates under severe shock. ammonium nitrate, chlorine trifluoride Yellow - 4 Readily undergoes explosive decomposition or detonates at normal temperature and pressure. TNT, nitroglycerine White - OX oxidizer hydrogen peroxide, ammonium nitrate White - W Reacts with water in a dangerous or unusual way. sulfuric acid, sodium White - SA simple asphyxiant gas Only: nitrogen, helium, neon, argon, krypton, xenon Science Laboratory Safety Signs What Does MSDS Mean? Know the Chemical Storage Color Codes What Is a Chemical Property? Ask a Chemistry Teacher Should I Use a Bug Bomb? How to Literally Set Ice On Fire What Is a Widowmaker in Forestry? Could Dragons Really Fly and Breath Fire? Here's the Science Here's What to Do If You Suspect a Meth Lab in Your Neighborhood Do You Know What a Chemical Element Is? How to Set Up a Home Chemistry Lab What You Need to Know About Smoke Bomb Safety What Is an Oxidant? Definition and Examples Where Do Matches Come From? A Delocalized Electron Defined in Chemistry What Does Each Alchemy Symbol Mean?