An elongated area of relatively high pressure, at a constant altitude, in the atmosphere. The opposite of an upper level trough. Upper level ridges are often oriented north-south, alternating between upper level troughs, however, during summer they may assume random orientations and vast dimensions. 

A written plan providing for timely recognition of approaching critical fire situations, priority setting, the deployment of forces, and other actions to respond to those situations.

A fully qualified individual who, in the absence of a superior, can be delegated the authority to manage a functional operation or to perform a specific task. In some cases, a deputy can act as relief for a superior, and, therefore, should be fully qualified in the position. Deputies generally can be assigned to the Incident Commander, EOC director, General Staff, and branch directors.

Person responsible to the Compensation/Claims Unit Leader for administrative matters arising from serious injuries and fatalities occurring on the incident.

Radio equipment with transmitters in mobile units on the same frequency as the base station, permitting conversation in two directions using the same frequency in turn.

A group of trained firefighters stationed at a dispatch point for quick, rapid deployment.

Refers to the joint consideration of both the life and physical well-being of individuals.

A temperature scale on which 320 F denotes the temperature of melting ice, and 2120 F the temperature of boiling water, both under standard atmospheric pressure.

Decomposition of material by the application of heat and oxidation. Also applied to propellants and other pyrotechnic mixtures, though the proper term there is "reacting". Also often an element of the crime of arson.

A simple role-play simulation technique that challenges participants to make decisions and communicate those decisions to others. A tactical decision game is an experiential learning method that is tactical in nature and has time and information constraints to put participants under some level of stress.