A 3 in the red section of a hazard diamond indicates a serious flammability hazard. It means the liquid or solid can ignite under almost all ambient temperature conditions and will readily burn.
3-Can cause serious injury despite medical treatment. 4-Can cause death or major injury despite medical treatment. The red diamond, appearing at the top of the label, conveys Flammability Hazard information.
The hazard diamond (formally known as the NFPA 704 system) is a quick, visual warning label for hazardous materials. It is divided into four color-coded quadrants. The three colored sections use a 0-to-4 number scale (where 4 is the most severe hazard), while the bottom white section uses specific symbols.
The hazard diamond (formally the NFPA 704 system) uses numbers from 0 (no hazard) to 4 (severe hazard) to communicate chemical risks. The numbers appear in three colored quadrants, while the fourth (white) quadrant indicates special hazards.
An NFPA Health Rating of 3 denotes "Extreme Danger" and signifies that short-term exposure can cause serious temporary or residual injury. Materials with this rating require full bodily protection and strict safety protocols.
NFPA 3 is the standard for the commissioning of fire protection and life safety systems. It provides the minimum procedural requirements to ensure active and passive life safety systems perform in conformity with the owner's project requirements, governing laws, codes, and intended design criteria.
There are three categories for flammable liquids, Category 1, 2 and 3, and one category for combustible liquids, Category 4, that you may see on the safety data sheet (SDS). Categories 1 and 2 will have the signal word “Danger” while categories 3 and 4 will have “Warning”.
The red diamond in the NFPA 704 system sits at the top (12 o'clock position) of the safety sign and indicates a flammability hazard. It uses a standardized scale of 000 to 444 to tell emergency responders exactly how easily the material will ignite and burn.
NFPA 3 is a recommended guide intended to address the administrative and procedural concepts of commissioning fire protection systems while NFPA 4 addresses testing the performance of the interconnection between multiple fire protection and life safety systems.
White NFPA Diamond
At the bottom of the NFPA diamond you will find a white area, which is used for special hazards. Rather than using numbers in this section you will see a letter or symbol. The most common of these is a W, which is used to indicate that the chemical has an unusual reaction when exposed to water.
The flammable liquid hazard symbol is a red diamond containing a black flame icon on a white background. This universal warning sign alerts you to liquids easily catching fire when exposed to an ignition source.
Diamond-shaped markers (most commonly white with orange borders) generally indicate dangers and restricted areas in boating and waterway navigation.
The primary toxic hazard symbol is the skull and crossbones. It consists of a black skull over two crossed bones inside a white, red-bordered diamond. This Globally Harmonized System (GHS) pictogram warns that a substance causes immediate, severe, or fatal acute toxicity if inhaled, ingested, or absorbed through the skin.
A Flammable Liquid Category 3 (Class 3) is a hazardous material that has a flashpoint at or above 73.4 ∘F (23 ∘C) and at or below 140 ∘F (60 ∘C).
The approved special hazard symbols are W, OX and SA. W indicates the material has an unusual reactivity with water and is a caution regarding the use of water in either firefighting or spill control response. OX indicates that the material is an oxidizer which can burn without the presence of oxygen.
0-4 0-least hazardous 4-most hazardous 1-4 1-most severe hazard 4-least severe hazard • The Hazard category numbers are NOT required to be on labels but are required on SDSs in Section 2.
The blue, red, and yellow fields (health, flammability, and reactivity) all use a numbering scale ranging from 0 to 4. A value of zero means that the material poses essentially no hazard; a rating of four indicates extreme danger.
The formula for damage reduction is (4 × level)% for each armor piece, for a maximum damage reduction of 64% if all armor pieces are enchanted with Protection IV. Unlike some of the other armor enchantments (e.g. Blast Protection), Protection offers no side effects outside of damage reduction.
The “three times rule” found in NFPA 13 states that “sprinklers shall be positioned away from obstructions a minimum distance of three times the maximum dimension of the obstruction.” For example, if a ceiling fan hub measures 4 inches by 7 inches, the sprinkler must be positioned at least 21 inches away from the hub.
1 = Materials that can cause significant irritation. 2 = Materials that can cause temporary incapacitation or residual injury. 3 = Materials that can cause serious or permanent injury. 4 = Materials that can be lethal.
Avoid these common compliance-driven mistakes:
The top red diamond on a hazard identification system (NFPA 704) label indicates a flammability hazard.
Yes. Under classification systems like the Globally Harmonized System (GHS), Category 1 represents the highest severity of hazard within a specific class. Category 2 and 3 substances are progressively less hazardous.
Examples of Class 3 Flammable Liquids include acetaldehyde, petroleum ether, and ethyl chloride. Class 3 “Combustible” liquids are those with a flashpoint above 100 degrees and below 200 degrees Fahrenheit. Acetone, benzene, and methyl alcohol are all examples of Class 3 Combustible Liquids.
Class A fires – are fires involving organic solids like paper, wood, etc. Class B fires – are fires involving flammable liquids. Class C fires – are fires involving flammable gasses. Class D fires – are fires involving burning metals (eg aluminium swarf)