The Hazardous Materials Identification System, or HMIS for short, is a numerical system for rating hazards in the workplace that was developed by the American Coatings Association. Although the system is voluntary, it can help employers stay in compliance with OSHA standards. HMIS is a system that uses easy-to-understand labels with colors and numbers to accurately communicate and convey hazards of chemicals being used in the facility.
The format of HMIS labels are four bars, all different colors, stacked on top of each other. Next to the bar is a box where the rating is printed. Four colored bars, similar to the colors used in the NFPA diamond, that represent the following different types of hazards:
- Blue: Indicates health hazards. In addition to the box for numerical ratings, there is another box. Chemicals that may cause chronic health problems are marked with an asterisk in the box, while a slash is used for substances that do not cause chronic health issues.
- Red: The flammability of the chemical.
- Orange: Represents physical hazards present. It should be noted that before 2002, this bar was yellow and stood for reactivity.
- White: Indicates which personal protective equipment (PPE) should be used when handling the material. White is the one color on the HMIS label that is not aligned with the NFPA diamond.
Additionally, the white color bar that assigns PPE uses an alphabetical code with letters A through K that represents either a single piece of PPE or a combination. For instance, an “A” printed on an HMIS label means the worker should put on safety glasses, but an “E” calls for eye protection, safety gloves, and a respirator.
Each color bar has its own specific criteria for the numerical rating of the hazard, but generally a rating of four is used for severe hazards, and zero indicates minimal hazard present. The rating system does follow what is outlined in NFPA 704: The Standard System for the Identification of the Hazards of Materials for Emergency Response.