Hazardous Materials Identification System. The Hazardous Materials Identification System (HMIS) is a numerical hazard rating that incorporates the use of labels with color developed by the American Coatings Association as a compliance aid for the OSHA Hazard Communication Standard. 1 HMIS Color Bar.
Definition of greenhouse gas. : any of various gaseous compounds (such as carbon dioxide) that absorb infrared radiation, trap heat in the atmosphere, and contribute to the greenhouse effect.
The greenhouse effect is the term used to describe the heating of the Earth's surface and lower atmosphere that is caused by the absorption and emission of infrared radiation by certain greenhouse gases. The principal greenhouse gas in the atmosphere is water vapor. î î î.