Fire BehaviorIntermediate

SFFMA Objectives: 15-02.01 – 15-02.022Hrs received

SFFMA Objectives15-02.01 Trainee shall define the following

units of measurements: A. British Thermal Unit (BTU)B. Fahrenheit (F)C. Celsius (C) D. Calorie (C)E. Joule, the SI unit for energy

15-02.02 Trainee shall define thermal balance and imbalance.

Units of Measurement for HeatBritish Thermal Units (BTU)

The amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit

While not used in scientific and engineering texts, the Btu is still frequently used in the fire service

Units of Measurement for HeatFahrenheit

Of or relating to a temperature scale that registers the freezing point of water as 32° and the boiling point as 212° at one atmosphere of pressure

CelsiusOf or relating to a temperature scale that

registers the freezing point of water as 0° and the boiling point as 100° under normal atmospheric pressure.

Units of Measurement for HeatCalorie:

Any of several approximately equal units of heat, each measured as the quantity of heat required to raise the temperature of 1 gram of water by 1°C from a standard initial temperature, especially from 3.98°C, 14.5°C, or 19.5°C, at 1 atmosphere pressure. Also called gram calorie, small calorie.

The unit of heat equal to 1/100 the quantity of heat required to raise the temperature of 1 gram of water from 0 to 100°C at 1 atmosphere pressure

Units of Measurement for HeatJoule – SI Unit for energy

The International System unit of electrical, mechanical, and thermal energy. A unit of electrical energy equal to the work done

when a current of one ampere is passed through a resistance of one ohm for one second.

A unit of energy equal to the work done when a force of one newton acts through a distance of one meter.

Thermal BalanceThermal Balance:

The degree of thermal balance existing in a closed room during a fire's development is dependant upon fuel supply and air availability as well as other factors. The hot area over the fire (often termed the fire plume or thermal column) causes the circulation that feeds air to the fire. However, when the ceiling and upper parts of the wall linings become super-heated, circulation slows down until the entire room develops a kind of thermal balance with temperatures distributed uniformly horizontally throughout the compartment. In vertical terms the temperatures continuously increase from bottom to top with the greatest concentration of heat at the highest level.

Thermal BalanceWhat does thermal balance mean to the Fire

Service and what can it teach us?