Heat Release Rate of an Open Kitchen Fire of Small Residential Units in Tall Buildings

In the Far East, many small units of residential buildings over 200 m tall are fitted with open kitchens. Fire safety provisions of these kitchens are determined by performance-based design (PBD). In most PBD projects, only the spread of smoke from the kitchen fire to the outside was studied. However, a fire load survey in Hong Kong indicated that large quantities of combustibles are stored in residential units. Cooking oil was found to be ignited easily even when using induction cookers. The burning of all combustibles in a big post-flashover fire needs to be studied. A database of heat release rates for local combustible products is not yet available. Estimations are based on very crude assumptions of low radiative heat flux in most of the PBD projects, and they are not supported by fullscale burning tests. In this paper, heat release rate for an open kitchen fire will be studied by the principle of superposition. The important issues in the estimation of heat release rate will be addressed and discussed. An example calculation of achieving low values of heat release rate will also be illustrated. The authority having jurisdiction is recommended to review such approach.