Hazardous Materials Identification System (HMIS)

Hazardous Materials Identification System – There are many hazardous materials that pose dangers to those who are exposed to them, including building occupants, members of nearby structures, and emergency responders. The physical states and composition of these materials vary greatly. The risks or dangers posed by these materials are different, and each one must be evaluated in view of the state it is in and how it will be handled or stored. The construction requirements, fire protection systems, operations, and response strategies associated with these materials are also different due to the wide variety of materials and hazards. Hence, the need to able to identify hazardous materials in an orderly manner.


Brief History of Hazardous Materials Identification System (HMIS)

The American Coatings Association developed the Hazardous Materials Identification System (HMIS) as a compliance aid for the OSHA Hazard Communication (HazCom) Standard. The HMIS Color Bar is similar to the fire diamond, which was developed by the National Fire Protection Association (NFPA). Both the fire diamond and the color bar had blue, red, white, and yellow sections prior to 2002. With the release of HMIS III in April 2002, the color bar changed from yellow, which represented reactivity, to orange, which represented physical danger. When emergency situations necessitate information regarding the effects of brief, or acute, exposure, the fire diamond was created. The color bar is used to show general health warning info and is not for emergencies.

Both systems were developed at a time when OSHA only required the use of some system without specifying a format and there was no mandated labeling system for communicating workplace chemical hazards. Although it does not mandate the use of GHS in the workplace, OSHA released an updated version of their HazCom standard in 2012 called HazCom 2012, which mandates the use of GHS labels on shipped containers and updated requirements for workplace labels that are compatible with GHS.

The HMIS Color Bar complies with these new requirements. Specifically, when employing HMIS III, which takes into consideration, aerosols’ increased flammability risk. The four bars are color-coded using contemporary color bar symbols, with blue representing the level of health risk, red representing flammability, orange representing a physical risk, and white representing Personal Protection. The ratings for the numbers range from 0 to 4.

The Hazardous Materials Identification System (HMIS) helps businesses comply with the Hazard Communication Standard (HCS) set forth by the Occupational Safety and Health Administration (OSHA).

Workers handling chemicals are able to quickly identify the relevant risks thanks to the system’s labeling practices, which also provide useful information like the product’s risk severity.


The HMIS Color Bar

Blue: The material’s health risks are explained in the Health section. The Health bar in the most recent version of HMIS has two spaces, one for an asterisk and the other for a numerical hazard rating. If the asterisk is present, it indicates a chronic health hazard, showing that prolonged exposure to the material could result in health issues like kidney damage or emphysema. Overexposures, such as those to hydrogen cyanide, can cause serious, permanent, or even life-threatening harm. This is the rating and its meaning;

  • 3. Without prompt action and medical attention, serious injury is likely to


  • 2. Diethyl ether, for instance, may cause minor or brief harm.
  • 1. Possible irritation or a minor, reversible injury.
  • 0. There is no significant health risk.


Red (Flammability): The criteria used to assign numerical values to HMIS I and II—ranging from 0 for low hazard to 4 for high hazard—are the same as those used by NFPA. In other words, HMIS I and II are the same as NFPA. For HMIS III, the flammability criteria are set by OSHA standards which add higher flammability ratings for aerosols. HMIS II descriptions are shown below, excluding the new aerosol criteria. Gases that are flammable or very volatile liquids that are flammable with flash points below 73 °F (23 °C) and boiling points below 100 °F (38 °C). Air can spontaneously ignite materials, like propane.

Here are the ratings for colour red;

  • materials that are able to ignite at almost any normal temperature including liquids with flash points between 73 and 100 degrees Fahrenheit as well as flammable liquids with boiling points above 100 degrees Fahrenheit (38 degrees Celsius).
  • Materials that must either be heated to a moderate temperature or exposed to high ambient temperatures before they will ignite including liquids such as diesel fuel with a flash point below 200 °F (93 °C) but above 100 °F (38 °C).
  • materials that must first be heated before they can ignite which includes liquids, solids, and semisolids with a flash point above 200 degrees Fahrenheit (93 degrees Celsius), such as canola oil.
  • Materials that won’t burn (like water, for example)


Orange (Reactivity/Physical Hazard): The OSHA physical hazard criterion is used to evaluate reactivity hazards. There are seven distinct hazard categories namely: Explosives, organic peroxides, water reactants, compressed gases, pyrophoric materials, oxidizers, and unstable reactants.

Here are the ratings and meanings

  • At normal temperature and pressure, materials that are quickly capable of explosive water reaction, detonation or explosive decomposition, polymerization, or self-reaction
  • Materials that are capable of detonation or an explosive reaction in the presence of a powerful initiating source and can combine with water to form explosive mixtures. At normal temperature and pressure, materials may polymerize, decompose, self-react, or undergo other chemical changes with a moderate risk of explosion (ammonium nitrate, for example).
  • At normal temperature and pressure, materials that are unstable and can undergo violent chemical changes without exploding. When exposed to air, substances like potassium and sodium can violently react with water or produce peroxides.
  • Materials that are typically stable but have the potential to become unstable (self-react) at high temperatures and pressures. In the absence of inhibitors, substances may not violently react with water or undergo hazardous polymerization (such as propene).
  • Materials that will not react with water, polymerize, decompose, condense, or self-react and are typically stable even under fire conditions. Explosives (like helium, for example)


White (Personal Protection): This is by far the most significant distinction between the HMIS and NFPA systems. It identifies the appropriate personal protective equipment (PPE) for handling the material. On the HMIS label, the only color that is not aligned with the NFPA diamond is white. A letter-code system is used on standard HMIS labels to identify particular PPE combinations.

The following is the standard HMIS letter code system for personal protective equipment:

A: Only requires safety glasses.

B: requires protective gloves and safety glasses and an apron. Requires a face shield, gloves, and an apron to protect one’s face

C: requires protective gloves, safety glasses, and an apron.

D: requires a face shield, gloves, and an apron to protect one’s face

E: requires dust respirators, protective gloves, and safety glasses

F: requires a dust respirator, safety glasses, a protective apron, and gloves

G: requires a vapor respirator, protective gloves, and safety glasses

H: requires a vapor respirator, protective gloves, a protective apron, and chemical splash goggles.

I: requires dust and vapor-resistant respirators, protective gloves, and safety glasses

J: Chemical splash goggles, protective gloves, a protective apron, and a dust- and vapor-resistant respirator are all required.

K: requires a full hazmat suit, hazmat boots, and an airline respirator mask or hood (for example, a complete CBRN protection kit), reserved for local uses, like site-specific labeling.

The meanings of the letter codes L to Z vary from location to location. Specific descriptions can be obtained from the facility’s supervisor, safety officer, or hazmat specialist.

Some label manufacturers may use pictograms to depict the recommended equipment, while others may print variant labels with tick boxes for each type of PPE. Take, for instance, a pallet box with a variant HMIS label in the white section that features pictograms for safety glasses, gloves, and a dust respirator. This label is equivalent to a standard label with the HMIS letter code E.


Versions and Labeling Differences

The National Paint and Coatings Association (NPCA) released the first version of the HMIS, known as HMIS I, several years before changing its name to the current ACA. The only significant differences exist between the labeling and formats of the outdated HMIS I and II labels and those of the current HMIS III and IV, despite the fact that the HMIS has been revised three times, the most recent of which is HMIS IV.

Reactivity was the third type of hazard in HMIS I and II, and it was marked with a yellow stripe. The yellow section of the NFPA Fire Diamond uses the same definition of reactivity as this older version does. The numbers for each risk level ranged from 0 (low risk) to 4 (high risk).

The third hazard type was given a new name, Physical Hazard, in HMIS III, and the yellow stripe was replaced with an orange one. The most recent definitions only apply to labels with the orange Physical Hazard symbol.

These changes were made by the ACA for two reasons: consistence with the OSHA’s meaning of an actual peril and further distinctive the HMIS from the Fire Jewel.

The corresponding hazard levels cannot be used interchangeably with the most recent Physical Hazard definitions.

If you see an older HMIS label with the word “Reactivity” and a yellow stripe, it was made to obsolete HMIS I or II specifications. To avoid misunderstandings, the ACA recommends replacing outdated labels with recent versions whenever possible.

Furthermore, the definitions that were applied to the numerical hazard levels of flammability under HMIS I and II were identical to those that were applied to the red section of the NFPA Fire Diamond. In contrast, the second revision, HMIS III, included a revised definition that was in line with OSHA guidelines.


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