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Large Fire Research Facility


As the federal government's principal fire research laboratory, EL maintains some of the country's best and most extensive fire testing facilities. More than 400 fire experiments are performed each year in the specially equipped, 27 m (90 ft) x 37 m (120 ft), Large Fire Research Facility.

Specifications / Capabilities:

The facility has three instrumented hoods or calorimeters for measuring heat release rate. Heat release rate is the amount of energy given off by a burning object. The energy is measured in kilowatts (kW). Heat release rate is a primary property used by fire protection engineers for making fire hazard assessments with computer fire models. A small trash can loaded with paper products has a heat release rate of approximately 50 kW. Physically a fire with a heat release rate of 50 kW has flames approximately 0.6 m (2 ft) high with a base of 0.3 m (1 ft) on each side.

The small calorimeter has a capacity of 50 kW and a hood 1.2 m (4 ft) on each side. It is used for measuring the heat release rate of small objects or samples removed from larger objects.

The medium sized calorimeter or furniture calorimeter, has a capacity of approximately 750 kW. This calorimeter is sized for burning individual pieces of furniture or other objects of similar size with a hood measuring 3 m (10 ft) on each side.

The large hood is approximately 5 m (16 ft) x 6 m (20ft) and has a capacity of 3 MW (3,000 kW). Several items can be burned under this calorimeter at one time. Burn rooms built to simulate portions of a building or a house can be installed adjacent to the large room. The smoke from the room fires flow into the large hood for measurement and exhaust from the building.

The Large Fire Research Facility has a variety of instrumentation for measuring temperature, mass, pressure, thermal radiation, real time gas concentrations for oxygen, carbon dioxide, carbon monoxide, nitrogen oxides and hydrocarbons, and smoke concentration. Several computerized data acquisition systems are available in the facility for recording the inputs from the instrumentation.

The facility also has pilot furnace for evaluating the fire endurance of wall assembly or floor/ceiling assembly test specimens measuring 1 m x 1 m.

Scientific Opportunities / Applications:

The facility has been used for measuring the heat release rate of a wide variety of items including crude oils, office and home furnishings, and transportation vehicle components. Data from many of the large fire experiments are used to develop or evaluate mathematical models and to study the fire performance of furnishings and interior finish materials. The open space in the facility has housed structures built to simulate living rooms, kitchens, offices, corridors, a townhouse, a bus, a portion of a train car. Measurements on fire suppression systems, such as sprinklers, water mist and gaseous agents, have also been conducted in the the Large Fire Research Facility.

Access Information:

For safety reasons, EL staff must closely supervise all use of the facilities.

BFRL Large Fire Laboratory

Name: Matthew Bundy
Phone: 301-975-6880
Fire Research Division
100 Bureau Drive, Stop 8660
Gaithersburg, MD 20899-8660