The energy release component (ERC) is a measure of the available energy (BTU/square foot) released per unit area in the flaming zone at the head of the fire. It is the least variable of the indices on a day-to-day basis, being a function solely of the fuels (and their moisture content, which is weather-dependent). ERC is another index produced by the Oklahoma Fire Danger Model. Conditions producing an ERC value of 24 represent a potential heat release twice that of conditions resulting in an ERC value of 12.
Since ERC represents the potential “heat release” per unit area in the flaming zone, it can provide guidance to several important fire activities. It may also be considered a composite fuel moisture value as it reflects the contribution that all live and dead fuels have to potential fire intensity. Especially for fuel complexes containing the heavier 100- and 1000-hour fuels, the ERC is a cumulative or “build-up” type of index. As live fuels cure and dead fuels dry, the ERC values get higher, thus providing a good reflection of drought conditions.
ERC is a function of the fuel model being used, the live and dead fuel moistures, and the weather conditions. If the fuel types and loads are substantially different than those in the fuel model being used, there will be inaccuracies.
120 David L. Boren Blvd., Suite 2900
Norman, OK 73072