The four bars are color-coded, using the modern color bar symbols with blue indicating the level of
health hazard, red for
flammability, orange for a physical hazard, and white for Personal Protection. The number ratings range from 0 to 4.
Blue (Health) The Health section conveys the health hazards of the material. In the latest version of HMIS, the Health bar has two spaces, one for an asterisk and one for a numeric hazard rating. (HMIS II descriptions, excluding the new aerosol criteria, are shown below) •
4. Flammable gases, or very volatile flammable liquids with flash points below , and boiling points below . Materials may ignite spontaneously with air (e.g.,
propane). •
3. Materials capable of ignition under almost all normal temperature conditions. Includes flammable liquids with flash points below and boiling points above , as well as liquids with flash points between 73 °F and 100 °F. •
2. Materials which must be moderately heated or exposed to high ambient temperatures before ignition will occur. Includes liquids having a flash point at or above but below (e.g.,
diesel fuel). •
1. Materials that must be preheated before ignition will occur. Includes liquids, solids and semi solids having a flash point above (e.g.,
canola oil). •
0. Materials that will not burn (e.g.,
Water).
Yellow/Orange (Reactivity/Physical Hazard) Reactivity hazards 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, and Unstable Reactives. The numerical ratings are very similar to
NFPA's yellow "Reactivity/Instability" rating according to the publicly available data, which is limited to "hazard statements" intended to accompany each rating (as shown below). However, HMIS is a proprietary system, and without referring to the actual criteria for each rating, it is not clear how similar they are. •
4. Materials that are readily capable of explosive water reaction, detonation or explosive decomposition, polymerization, or self-reaction at normal temperature and pressure (e.g.,
chlorine dioxide,
nitroglycerin). •
3. 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 (e.g.,
ammonium nitrate). •
2. 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 (e.g.,
potassium,
sodium). •
1. 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 (e.g.,
propene). •
0. Materials that are normally stable, even under fire conditions, and will not react with water, polymerize, decompose, condense, or self-react. Non-explosives (e.g.,
helium).
White (Personal Protection) This is by far the largest area of difference between the NFPA and HMIS systems. In the NFPA system, the white area is used to convey special hazards whereas HMIS uses the white section to indicate which personal protective equipment (PPE) should be used when working with the material. •
X. ask supervisor or safety specialist for handling instructions, or refer to the MSDS sheet for specific directions •
K. airline hood or mask, gloves, full suit and boots •
J. splash goggles, gloves, apron and a dust/vapor respirator •
I. safety glasses, gloves and a dust/vapor respirator •
H. splash goggles, gloves, apron and a vapor respirator •
G. safety glasses, a vapor respirator •
F. safety glasses, gloves, apron and a dust respirator •
E. safety glasses, gloves and a dust respirator •
D. face shield, gloves and an apron •
C. safety glasses, gloves and an apron •
B. safety glasses and gloves •
A. safety glasses ==Comparisons with NFPA 704==