HMIS® - Hazardous Materials Identification System

The Hazardous Materials Identification System, HMIS®, was developed by the National Paint & Coatings Association (NPCA), now known as the American Coatings Association], to help employers comply with OSHA's Hazard Communication (HCS), 29 CFR 1910.1200.

The system utilizes colored bars, numbers and symbols to convey the hazards of chemicals used in the workplace. HMIS® should not be confused with either the Canadian WHMIS system. Nor should HMIS® labels (colored horizontal bars) be confused with NFPA labels (colored diamonds). The two systems are similar but not identical.

HMIS® labels can appear in a variety of formats. Some will include additional spaces to list target organ effects, a labeling requirement under 29 CFR 1910.1200, and other information, but the four colored areas shown here will always be present.

An older style HMIS® label is shown below on the left. In the April 2002 release of HMIS® III the yellow Reactivity section was replaced with an orange Physical Hazard section as shown below on the right. Other aspects of the system were also changed (see below).

label examples

label examples

MSDS Relevance

Specific sections of an HMIS® label include the following:


    • The Health section conveys the health hazards of the material. In the latest version of HMIS®, the blue Health bar has two spaces, one for an asterisk and one for a numeric hazard rating.

      If present, the asterisk signifies a chronic health hazard, meaning that long-term exposure to the material could cause a health problem such as emphysema or kidney damage. NFPA lacks this important information because the NFPA system is meant only for emergency or acute (short-term) exposures.

      According to NPCA, the numeric hazard assessment procedure is different than that used by NFPA. Here are the numeric rankings for the HMIS system:


    Life-threatening, major or permanent damage may result from single or repeated overexposures.


    Major injury likely unless prompt action is taken and medical treatment is given.


    Temporary or minor injury may occur.


    Irritation or minor reversible injury possible.


    No significant risk to health.


    • For HMIS I and II, the criteria used to assign numeric values (0 = low hazard to 4 = high hazard) are identical to those used by NFPA. In other words, in this category, the systems are identical.

    • For HMIS III, the flammability criteria are defined according to OSHA standards:


    Flammable gases, or very volatile flammable liquids with flashpoints below 73 °F, and boiling points below 100 °F. Materials may ignite spontaneously with air. (Class IA).


    Materials capable of ignition under almost all normal temperature conditions. Includes flammable liquids with flashpoints below 73 °F and boiling points above 100 °F, as well as liquids with flashpoints between 73 °F and 100 °F. (Classes IB & IC).


    Materials which must be moderately heated or exposed to high ambient temperatures before ignition will occur. Includes liquids having a flashpoints at or above 100 °F but below 200 °F. (Classes II & IIIA).


    Materials that must be preheated before ignition will occur. Includes liquids, solids and semi solids having a flashpoint above 200 °F. (Class IIIB).


    Materials that will not burn.

    Reactivity (HMIS® I and II - now obsolete)

    • The criteria used to assign numeric values (0 = low hazard to 4 = high hazard) were identical to those used by NFPA.

      This version is now obsolete. The yellow section has been replaced with an orange section titled Physical Hazards - see the next section for more information.

    Physical Hazard (HMIS® III)

    • Reactivity hazard are assessed using the OSHA criterion of physical hazard. Seven such hazard classes are recognized:

      • Water Reactives
      • Organic Peroxides
      • Explosives
      • Compressed gases
      • Pyrophoric materials.
      • Oxidizers
      • Unstable Reactives

      This version replaces the now-obsolete yellow section titled Reactivity - see the previous section for more information. As with the Health and Flammability sections, the level of hazard is indicated using numeric values (0 = low hazard to 4 = high hazard):


    Materials that are readily capable of explosive water reaction, detonation or explosive decomposition, polymerization, or self-reaction at normal temperature and pressure.


    Materials that may form explosive mixtures with water and are capable of detonation or explosive reaction in the presence of a strong initiating source. Materials may polymerize, decompose, self-react, or undergo other chemical change at normal temperature and pressure with moderate risk of explosion.


    Materials that are unstable and may undergo violent chemical changes at normal temperature and pressure with low risk for explosion. Materials may react violently with water or form peroxides upon exposure to air.


    Materials that are normally stable but can become unstable (self-react) at high temperatures and pressures. Materials may react non-violently with water or undergo hazardous polymerization in the absence of inhibitors.


    Materials that are normally stable, even under fire conditions, and will not react with water, polymerize, decompose , condense, or self-react. Non-explosives.

    Personal Protection

    • HMIS® uses the white section to indicate what personal protective equipment (PPE) should be used when working with the material. A letter coding system is used for this section.

    The lettering scheme is as shown below along with a series of graphics meant to reinforce the meaning of each letter:
    HMIS® Letter Required Equipment


    Safety Glasses


    Safety GlassesGloves


    Safety GlassesGlovesApron


    Full Face ShieldGlovesApron


    Safety GlassesGlovesDust


    Safety GlassesGlovesApronDust


    Safety GlassesGlovesVapor


    Safety GogglesGlovesApronVapor


    Safety GlassesGlovesDustVapor


    Safety GogglesGlovesApronDustVapor


    Airline Hood or MaskGlovesFull protective suitBoots

    L through Z

    Site-specific label. Ask your supervisor or safety specialist for handling instructions