NFPA 704

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NFPA 704
fire diamond
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineHealth code 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineReactivity code 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard W: Reacts with water in an unusual or dangerous manner. E.g. sodium, sulfuric acidNFPA 704
3
1
2
W

"NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response" is a standard maintained by the U.S.-based National Fire Protection Association. First "tentatively adopted as a guide" in 1960, [1] and revised several times since then, it defines the colloquial "Safety Square" or "Fire Diamond" used by emergency personnel to quickly and easily identify the risks posed by hazardous materials. This helps determine what, if any, special equipment should be used, procedures followed, or precautions taken during the initial stages of an emergency response.

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National Fire Protection Association International nonprofit organization

The National Fire Protection Association (NFPA) is an international nonprofit organization devoted to eliminating death, injury, property and economic loss due to fire, electrical and related hazards. In 2018, the NFPA claims to have 50,000 members and 9,000 volunteers working with the organization through its 250 technical committees.

Contents

Codes

Flammability (red): no hazard codeHealth (blue): no hazard codeReactivity (yellow): no hazard codeSpecial hazards (white): no codeNFPA 704

The four divisions are typically color-coded with red on top indicating flammability, blue on the left indicating level of health hazard, yellow on the right for chemical reactivity, and white containing codes for special hazards. Each of health, flammability and reactivity is rated on a scale from 0 (minimal hazard) to 4 (severe hazard). The latest version of NFPA 704 sections 5, 6, 7 and 8 for the specifications of each classification are listed below. The numeric values in the first column are designated in the standard by "Degree of Hazard" using Arabic numerals (0, 1, 2, 3, 4), not to be confused with other classification systems, such as that in the NFPA 30 Flammable and Combustible Liquids Code, where flammable and combustible liquid categories are designated by "Class", using Roman numerals (I, II, III). [2]

Health is a state of physical, mental and social well-being in which disease and infirmity are absent.

In chemistry, reactivity is the impetus for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy.

Flammability (red)
0Materials that will not burn under typical fire conditions (e.g. Carbon tetrachloride), including intrinsically noncombustible materials such as concrete, stone, and sand. Materials that will not burn in air when exposed to a temperature of 820 °C (1,500 °F) for a period of 5 minutes.
1Materials that require considerable preheating, under all ambient temperature conditions, before ignition and combustion can occur (e.g. mineral oil, ammonia). Includes some finely divided suspended solids that do not require heating before ignition can occur. Flash point at or above 93.3 °C (200 °F).
2Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur (e.g. diesel fuel, paper, sulfur) and multiple finely divided suspended solids that do not require heating before ignition can occur. Flash point between 37.8 and 93.3 °C (100 and 200 °F).
3Liquids and solids (including finely divided suspended solids) that can be ignited under almost all ambient temperature conditions (e.g. gasoline, acetone). Liquids having a flash point below 22.8 °C (73 °F) and having a boiling point at or above 37.8 °C (100 °F) or having a flash point between 22.8 and 37.8 °C (73 and 100 °F).
4Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily (e.g. acetylene, propane, hydrogen gas). Includes pyrophoric substances. Flash point below room temperature at 22.8 °C (73 °F).

Health (blue)
0Poses no health hazard, no precautions necessary and would offer no hazard beyond that of ordinary combustible materials (e.g. wood, paper)
1Exposure would cause irritation with only minor residual injury (e.g. acetone, sodium bromate, potassium chloride)
2Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury (e.g. diethyl ether, ammonium phosphate, iodine)
3Short exposure could cause serious temporary or moderate residual injury (e.g. liquid hydrogen, sulfuric acid, calcium hypochlorite, hexafluorosilicic acid, zinc chloride)
4Very short exposure could cause death or major residual injury (e.g. hydrogen cyanide, phosgene, methyl isocyanate, hydrofluoric acid)

Instability–reactivity (yellow)
0Normally stable, even under fire exposure conditions, and is not reactive with water (e.g. helium, N2)
1Normally stable, but can become unstable at elevated temperatures and pressures (e.g. propene)
2Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water (e.g. white phosphorus, potassium, sodium)
3Capable of detonation or explosive decomposition but requires a strong initiating source, must be heated under confinement before initiation, reacts explosively with water, or will detonate if severely shocked (e.g. ammonium nitrate, cesium, hydrogen peroxide)
4Readily capable of detonation or explosive decomposition at normal temperatures and pressures (e.g. nitroglycerin, chlorine dioxide, nitrogen triiodide, manganese heptoxide)

Special notice (white)
The white "special notice" area can contain several symbols. The following symbols are defined by the NFPA 704 standard.
OX Oxidizer, allows chemicals to burn without an air supply (e.g. potassium perchlorate, ammonium nitrate, hydrogen peroxide).
WReacts with water in an unusual or dangerous manner (e.g. caesium, sodium, sulfuric acid).
SASimple asphyxiant gas (specifically helium, nitrogen, neon, argon, krypton, xenon). The SA symbol shall also be used for liquefied carbon dioxide vapor withdrawal systems and where large quantities of dry ice are used in confined areas. [2]
Non-standard symbols (white)
These hazard codes are not part of the NFPA 704 standard, but are occasionally used in an unofficial manner. The use of non-standard codes may be permitted, required or disallowed by the authority having jurisdiction (e.g. fire department).
COR Corrosive; strong acid or base (e.g. sulfuric acid, potassium hydroxide)
ACIDAcid or alkaline, to be more specific
ALK
BIO Biological hazard (e.g. flu virus, rabies virus)
Biohazard symbol.svg
POI Poisonous (e.g. strychnine, alpha-Amanitin)
RA Radioactive (e.g. plutonium, cobalt-60)
RAD
Radiation warning symbol2.svg
CRY Cryogenic (e.g. liquid nitrogen)
CRYO

See also

Globally Harmonized System of Classification and Labelling of Chemicals international system of classification of chemicals

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is an internationally agreed-upon standard managed by the United Nations that was set up to replace the assortment of hazardous material classification and labelling schemes previously used around the world. Core elements of the GHS include standardized hazard testing criteria, universal warning pictograms, and harmonized safety data sheets which provide users of dangerous goods with a host of information. The system acts as a complement to the UN Numbered system of regulated hazardous material transport. Implementation is managed through the UN Secretariat. Although adoption has taken time, as of 2017, the system has been enacted to significant extents in most major countries of the world. This includes the European Union, which has implemented the United Nations' GHS into EU law as the CLP Regulation, and United States Occupational Safety and Health Administration standards.

Hazard symbol recognisable symbol designed to warn about hazardous or dangerous materials, locations, or objects

Hazard symbols or warning symbols are recognisable symbols designed to warn about hazardous or dangerous materials, locations, or objects, including electric currents, poisons, and radioactivity. The use of hazard symbols is often regulated by law and directed by standards organisations. Hazard symbols may appear with different colors, backgrounds, borders and supplemental information in order to specify the type of hazard and the level of threat. Warning symbols are used in many places in lieu of or addition to written warnings as they are quickly recognized and more commonly understood.

Hazchem

Hazchem is a warning plate system used in Australia, Malaysia, New Zealand, India and the United Kingdom for vehicles transporting hazardous substances, and on storage facilities. The top-left section of the plate gives the Emergency Action Code (EAC) telling the fire brigade what actions to take if there's an accident or fire. The middle-left section containing a 4 digit number gives the UN Substance Identification Number describing the material. The lower-left section gives the telephone number that should be called if special advice is needed. The warning symbol in the top right indicates the general hazard class of the material. The bottom-right of the plate carries a company logo or name.

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Safety data sheet System for cataloging information, potential hazards and instructions for safe use associated with a material or product

A safety data sheet (SDS), material safety data sheet (MSDS), or product safety data sheet (PSDS) are documents that list information relating to occupational safety and health for the use of various substances and products. SDSs are a widely used system for cataloging information on chemicals, chemical compounds, and chemical mixtures. SDS information may include instructions for the safe use and potential hazards associated with a particular material or product, along with spill-handling procedures. The older MSDS formats could vary from source to source within a country depending on national requirements; however, the newer SDS format is internationally standardized.

Fire safety

Fire safety is the set of practices intended to reduce the destruction caused by fire. Fire safety measures include those that are intended to prevent ignition of an uncontrolled fire, and those that are used to limit the development and effects of a fire after it starts.

Process safety management

Process safety managementsystem is a regulation promulgated by the U.S. Occupational Safety and Health Administration (OSHA). A process is any activity or combination of activities including any use, storage, manufacturing, handling or the on-site movement of highly hazardous chemicals (HHCs) as defined by OSHA and the Environmental Protection Agency.

Dangerous goods Solids, liquids, or gases harmful to people, other organisms, property or the environment

Dangerous goods, abbreviated DG, are items or substances that when transported are a risk to health, safety, property or the environment. Hazardous materials are substances, solids, liquids, or gases that can harm people, other living organisms, property, or the environment, more specifically.

Chloroprene chemical compound

Chloroprene is the common name for 2-chlorobuta-1,3-diene (IUPAC name) with the chemical formula CH2=CCl−CH=CH2. Chloroprene is a colorless volatile liquid, almost exclusively used as a monomer for the production of the polymer polychloroprene, a type of synthetic rubber. Polychloroprene is better known as Neoprene, the trade name given by DuPont.

Electrical equipment in hazardous areas Electrical equipment in places where fire or explosion hazards may exist

In electrical engineering, hazardous locations are defined as places where fire or explosion hazards may exist due to flammable gases, flammable liquid–produced vapors, combustible liquid–produced vapors, combustible dusts, or ignitable fibers/flyings present in the air in quantities sufficient to produce explosive or ignitable mixtures. Electrical equipment that must be installed in such classified locations should be specially designed and tested to ensure it does not initiate an explosion, due to arcing contacts or high surface temperature of equipment.

NFPA 70E, titled Standard for Electrical Safety in the Workplace, is a standard of the National Fire Protection Association (NFPA). The document covers electrical safety requirements for employees. The NFPA is best known for its sponsorship of the National Electrical Code.

A placard is a notice installed in a public place, like a small card, sign, or plaque. It can be attached to or hung from a vehicle or building to indicate information about the vehicle operator or contents of a vehicle or building. It can also refer to paperboard signs or notice carried by picketers or demonstrators.

Mixtures of dispersed combustible materials and air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to as flammability limits or explosive limits. Combustion can range in violence from deflagration through detonation.

Flammable liquid any liquid that can catch fire

A flammable liquid is a combustible liquid which can be easily ignited in air at ambient temperatures, i.e. it has a flash point at or below nominal threshold temperatures defined by a number of national and international standards organisations.

Hazardous Materials Identification System A numerical hazard rating using colour coded labels

The Hazardous Materials Identification System (HMIS) is a numerical hazard rating that incorporates the use of labels with color developed by the American Coatings Association as a compliance aid for the OSHA Hazard Communication (HazCom) Standard.

Fire class is a term used to denote the type of fire, in relation to the combustion materials which have ignited. This has onward impacts on the type of suppression or extinguishing materials which can be used. Class letters are often assigned to the different types of fire, but these differ between territories. There are separate standards in the United States, Europe, and Australia.

Potassium nitrate is an oxidizer so storing it near fire hazards or reducing agents should be avoided to minimise risk in case of a fire.

Combustibility and flammability

Combustible materials are those which can combust, i.e. burn in air. Flammable materials are combustible materials that can be easily ignited at ambient temperatures whereas those that are harder to ignite are just considered combustible.

Grease duct

A grease duct is a duct that is specifically designed to vent grease-laden flammable vapors from commercial cooking equipment such as stoves, deep fryers, and woks to the outside of a building or mobile food preparation trailer. Grease ducts are regulated both in terms of their construction and maintenance, forming part of the building's passive fire protection system. The cleaning schedule is typically dictated by fire code or related safety regulations, and evidence of compliance must be kept on file by the owner.

Fire extinguisher An active fire protection device

A fire extinguisher is an active fire protection device used to extinguish or control small fires, often in emergency situations. It is not intended for use on an out-of-control fire, such as one which has reached the ceiling, endangers the user, or otherwise requires the expertise of a fire brigade. Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent which can be discharged to extinguish a fire. Fire extinguishers manufactured with non-cylindrical pressure vessels also exist but are less common.

Pipe marking is the usage of labels, typically color coded, to identify the use, contents and flow direction of pipes inside of industrial and commercial buildings. This information assists personnel when carrying out maintenance and emergency personnel when responding to emergencies.

References

  1. Dr. W. H. L. Dornette, Miles E. Woodworth (1969). "Proposed Amendments on Revisions to the Recommended System for the Identification of The Fire Hazards of Materials / NFPA No. 704M — 1969" (PDF). National Fire Protection Association . Retrieved 2016-03-04.CS1 maint: uses authors parameter (link)
  2. 1 2 "NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response". 2017.
Milwaukee Largest city in Wisconsin

Milwaukee is the largest city in the state of Wisconsin and the fifth-largest city in the Midwestern United States. The seat of the eponymous county, it is on Lake Michigan's western shore. Ranked by its estimated 2014 population, Milwaukee was the 31st largest city in the United States. The city's estimated population in 2017 was 595,351. Milwaukee is the main cultural and economic center of the Milwaukee metropolitan area which had a population of 2,043,904 in the 2014 census estimate. It is the third-most densely populated metropolitan area in the Midwest, surpassed only by Chicago and Detroit, respectively. Milwaukee is considered a Gamma global city as categorized by the Globalization and World Cities Research Network with a regional GDP of over $105 billion.

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The University of Oregon is a public flagship research university in Eugene, Oregon. Founded in 1876, the institution's 295-acre campus is along the Willamette River. Since July 2014, UO has been governed by the Board of Trustees of the University of Oregon. The university has a Carnegie Classification of "highest research activity" and has 19 research centers and institutes. UO was admitted to the Association of American Universities in 1969.