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OSU Rate of Heat Release Apparatus

FAR 25.853 (a-1), FAA Fire Test Handbook – Chapter 5,
ASTM E906 Standard Test Method for Heat and Visible Smoke Release Rates for Materials and Products

The OSU Rate of Heat Release Apparatus is used to expose aircraft interior cabin materials to an incident radiant heat flux of 35 kW/m2, to comply with FAR 25.853 [a-1] requirements. The apparatus, built in accordance with FAA Fire Test Handbook, Chapter 5, is provided in three parts: test chamber, control unit and data acquisition and analysis system. It consists of:

  • Stainless steel insulated test chamber, with gasketed door and viewing window
  • Matched set glow bars elements as heat source (with corrosion-resistant stainless steel housing)
  • Dual glo-bar power controllers for ease of heat flux uniformity adjustment
  • Upper pilot, lower pilot with spark ignition and calibration methane gas burners
  • Thermopile for heat measurement, with five hot thermocouple junctions in chimney and five cold thermocouple junctions in the air chamber
  • Air distribution system and exhaust stack
  • Specimen holder, with pressure plate, mounting bracket and drip pan
  • Stand-alone Control Unit Housed in 19" Rack, with
    - Thyrister control for radiant heat source
    - Flow control for burners
    - Controls for air supply system
  • Calibration heat flux meter
  • Software, interface, computer and laser printer

The unit can also be modified to comply with ASTM E906 and to conduct tests at different incident heat fluxes, for research purposes. It can be supplied with several options: smoke measurement system (white light or laser, as in picture above), oxygen depletion calorimetry and facilities for monitoring sample mass loss continuously.

FTT also offer a data acquisition and analysis stand-alone software package for the OSU that can be used either with our instrumentation or with existing equipment.

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