Burning of a Polyurethane Slab in Open and in Room Environments

  • Sho Akao
  • Kazunori HaradaEmail author
  • Daisaku Nii
  • Sungchan Lee
  • Junghoon Ji
  • Tsuneto Tsuchihashi
Conference paper


To examine the effect of thermal feedback during a fire in a compartment, flexible polyurethane slab was burnt in an open environment and in a model-scale room. The size of the slab was 500 × 500 mm. The thickness was varied between 50 and 200 mm. The size of model-scale room was 900 × 1700 mm in plan area. Opening height was changed in the range of 200–800 mm to examine the effect of ventilation and smoke layer thickness. The ceiling height was varied in the range of 400–800 mm to examine the effect of extended flame under ceiling. The polyurethane slab was ignited at the center of top surface. Spread of flame was observed and recorded by video cameras. Mass loss rate, temperature profile, and heat fluxes to ceiling and floor were measured. Experimental results show that the thermal feedback effect is clearly observed even in the case of high ceiling with large openings. As the opening height was reduced, the effect of thermal feedback was increased moderately. At maximum, the heat release rate was increased to 170% of that in open burning. The effect of ceiling height was nonlinear. As the ceiling height was decreased comparable to continuous flame height, heat release rate was greatly increased due to the thermal feedback from extended flame under ceiling. Using the measured data, the effect of thermal feedback was correlated with heat flux to floor. Empirical relationships between ceiling height and fire growth rate, between maximum heat release rate and burning type index were derived.


Fire source Thermal feedback Heat release rate per unit area Surface flame spread rate 



Burning area (m2)


Surface area of specimen (m2)


Opening area (m2)


Maximum HRR per unit area of burning surface (kW/m2)


HRR per unit area (kW/m2)


Average HRR per unit area during first 180 s of burning by cone calorimeter (kW/m2)


Heat release rate (kW)


Opening height (m)


Height (thickness) of specimen


Ceiling height (m)


Mass loss rate per unit area of burning surface [kg/(s m2)]


Radius of burning area (m)


Time (s)


Incubation time (s)


Total heat release (kJ)


Surface flame spread rate (m/s)


Opening width (m)


Initial mass of specimen (kg)

Greek symbols


Fire growth rate (kW/s2)


Burning type index (m1/2)


Heat of combustion (kJ/kg)






This research was financially supported by JSPS KAKENHI, Grant-in-Aid for Scientific Research (B), grant No. 26289204 during 2014–16 fiscal years by Japan Society for Promotion of Science.


  1. 1.
    International Organization for Standardization. (2015). ISO 16733-1, Fire safety engineering—Selection of design fire scenarios and design fires—Part 1: Selection of design fire scenarios.Google Scholar
  2. 2.
    International Organization for Standardization. (2008). ISO 24473, Fire tests—Open calorimetry—Measurement of the rate of production of heat and combustion products for fires of up to 40 MW.Google Scholar
  3. 3.
    Tanaka, T., & Yamada, S. (2004). BRI2002: Two layer zone smoke transport model. Fire Science and Technology, 23, 1–131.CrossRefGoogle Scholar
  4. 4.
    Utiskul, Y., & Quintiere, J. G. (2008). An application of mass loss rate model with fuel response effects in fully-developed compartment fires. In Proceedings of the 9th International Symposium, International Association for Fire Safety Science (pp. 827–838).Google Scholar
  5. 5.
    Mizukami, T., Utiskul, Y., & Quintiere, J. G. (2015). A compartment burning rate algorithm for a zone model. Fire Safety Journal, 79, 57–68.CrossRefGoogle Scholar
  6. 6.
    Wade, C., Fleischmann, C., Spearpoint, M., & Abu, A. (2017). Prediction model for compartment effects on burning upholstered furniture. In International Conference on Research and Advanced Technology in Fire Safety (pp. 315–330).Google Scholar
  7. 7.
    International Organization for Standardization. (2015). ISO 5660-1, Reaction-to-fire tests—Heat release, smoke production and mass loss rate—Part 1: Heat release rate (cone calorimeter method) and smoke production rate (dynamic measurement).Google Scholar
  8. 8.
    Heskestad, G. (2016). Fire plumes, flame height, and air entrainment. In The SFPE handbook of fire protection engineering (5th ed., Vol. 1, pp. 396–428). Society of Fire Protection Engineers.Google Scholar
  9. 9.
    Ohmiya, Y., Satoh, M., Tanaka, T., & Wakamatsu, T. (1995). Burning rate of fuel in enclosure and generation limit of the external flame. Journal of Construction Engineering, Transactions of AIJ, 469, 149–158. (in Japanese).CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • Sho Akao
    • 1
  • Kazunori Harada
    • 1
    Email author
  • Daisaku Nii
    • 1
  • Sungchan Lee
    • 1
  • Junghoon Ji
    • 1
  • Tsuneto Tsuchihashi
    • 2
  1. 1.Department of Architecture and Architectural EngineeringKyoto UniversityNishikyo, KyotoJapan
  2. 2.General Building Research Corporation of JapanSuita, OsakaJapan

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