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.
Methane as Greenhouse Gas. Greenhouse gases are gases which can warm the atmosphere, and, thereby, the oceans and the surface of the land. They are referred to as greenhouse gases because they operate in a fashion similar to the way a greenhouse works.