Fire & Safety Engineering

Research Leader : Prof. Chow Wan-ki
President, Asia-Oceania Association for Fire Science and Technology
President, Hong Kong Chapter, Society of Fire Protection Engineers (USA)

With the rapid increase in population in the Far East, especially the development of big cities and city groups in China, and the increasing number of non-accidental fires, fire ‘safety’ in dense urban areas has to be considered carefully. Big accidental fires had happened before in old high-rise buildings, cross-harbour tunnels and buses in Hong Kong; and in many old high-rise buildings and new shopping malls in China. Non-accidental fires reported over the world included the terrorist attack fires in the World Trade Center on 11 September, 2001 (WTC-911) in USA; arson fires in universities in Beijing; and underground railway arson fires in South Korea and Russia. Several arson fires were reported in Hong Kong in a bank, a karaoke, and an underground train vehicle. Fire safety should be examined carefully in new architectural features with deep-plan, high-rise, well-sealed and framed steel structure.

The overall aim of fire engineering research in the Department is to develop a scientific understanding of building fires and to establish an adequate theoretical basis for fire protection engineering for Hong Kong and the Mainland China. This includes the physical and chemical processes of material decomposition, fire ignition, flame properties, thermal radiation, fire spread mechanisms, smoke production and spreading mechanisms. With sound basic principles, the total fire safety concept can be implemented by working out appropriate hardware design on active fire control systems and passive construction elements; and software fire safety management.

Research Focus

Atrium hot smoke test

Research effort was directed on the mathematical modelling of fire for over 20 years. Detailed combustion chemistry is studied for upgrading the model to the post-flashover stage. Fire chemistry in burning poly(methyl methacrylate), poly (vinyl chloride) and polyurethane were studied. The development of a new fire model is in progress with combustion, turbulence and radiation. Different fire zone models were evaluated.

Another focused area is on fire suppression system. Sprinkler for new architectural features such as coverage of perimeter zone in an atrium is studied. Effort was made on studying long-throw sprinkler installed at height. New technology of water mist system was studied. Adverse effects of steam production and combustion enhancement were investigated. Bench-scale tests with a cone calorimeter and full-scale burning tests were carried out to study extinguishment chemistry with advanced chemical measuring technique. New areas on Video Detection System, and total flooding gas protection system with clean agent were also investigated. Effect of thermal radiation on extinguishing concentration of heptafluoropropane, suppression chemistry and fire retardants were studied.

Advanced topics in fire include studying atrium fires and performance-based design. There is a strong demand to have comprehensive fire regulations for atria, since many new big atria are being built in the local region. Results on fire research had been applied for advising the government Buildings Department in approving fire safety designs with the Fire Engineering Approach similar to Engineering Performance-Based Fire Code through their Fire Safety Committee since 1998. That was advised by Professor Chow from 1998 to 2004, and by Dr. Fong since 2004.

Other active projects are on hotel fires, industrial fires, improved fire safety in old high-rise buildings, evaluation of fire services systems, risk analysis of the new airport terminal buildings, bus and train vehicle fires and shopping mall fires. Professor Chow was involved in monitoring the development of new generation of fire safety codes; and implementation of performance-based design in SAR and Mainland.

Specialist Facilities

The Department laboratory houses three fire chambers (two 4 m x 3 m x 3 m and one 6 m x 3 m x 3 m) for full-scale burning tests. The chambers are equipped with detection instruments such as thermocouples, velocity sensors, oxygen analysers and gas analysers for measuring the heat release rates and fire environment. Fire protection systems including sprinkler systems, water mist systems, fire detection systems and smoke extraction systems are installed for studying system performance. A cone calorimeter is used for studying the heat release rates of building materials under controlled environment. Standard fire tests on materials, for the ease of ignitability, fire propagation index and the critical oxygen index flammability, etc., can be undertaken. Small wind tunnels for evaluating the thermal sensitivities of sprinkler heads and fire detectors are also available. Oxygen consumption calorimetry was developed with Harbin Engineering University, Harbin, Heilongjiang, China. A full-scale burning atrium of size (18 m x 12 m x 27 m) was developed at the State Key Laboratory of Fire Science, the University of Science and Technology of China, Hefei, Anhui, China.

Current Projects

  • Active fire protection in supertall buildings funded by the Croucher Foundation
  • Pyrolysis, ignition and combustion of different combustibles in buildings
  • Polymer-flame retardation in silicon/metal halide doped polymers
  • Thermal decomposition and combustion characteristics of polymeric materials under water mist application
  • Chemical kinetics of pyrolysis and combustion of combustibles for fire safe buildings
  • Theoretical analysis on buoyancy-induced turbulence encountered in building services engineering
  • Experimental studies on atrium fires and evaluation of the associated fire services system
  • Fire safety in train vehicles
  • Studies on the operation mode of selected environmentally clean fire extinguishments
  • Determination of the concentrations needed for extinguishing fires with clean agent heptafluoropropane (FM-200)
  • Fire safety for glass facades in green and sustainable buildings
  • The skybridge as an evacuation option for tall buildings in Hong Kong
  • Onsetting of internal fire whirls in buildings and associated safety provisions
  • Smoke emission in burning fire resisting glass with higher rating
  • Collaboration with University of Maryland on tunnel fires
  • Emergency evacuation in big halls and railway terminals
  • Fire safety in green or sustainable buildings
  • Risk analysis of escape time from residential buildings in Hong Kong
  • Fire safety in the residential care homes for the elderly persons in Hong Kong