On the use of reliability interval method and grey relational model for fire safety ranking of existing buildings

If buildings, which are designed to old prescriptive fire and building codes, are judged by current prescriptive standard, they may be considered to have "sub-standard" fire safety protection. Improvement works may be considered necessary. However, if improvement works are to be carried out at the same time, huge financial burden may be imposed on the society. Thus, prioritization of the improvement works on the basis of a holistic fire safety evaluation will even the cost burden over a period of time and maintain the fire safety in existing buildings within a reasonable level. Fire safety ranking methods have been developed in many countries to assist the evaluation of the fire safety level of buildings. Some of the methods adopting the multi-attribute evaluation approach may provide a fire safety audit from a holistic point of view. This approach can provide a simple evaluation and is particularly useful for complex multi-storey buildings. One of the problems of using multi-attribute evaluation approach is the manipulation of the imprecise information and definition of some of the fire safety attributes. In this paper, a new reliability interval method for manipulating the weightings of attributes and a synthetic model on the basis of grey system theory is presented. The proposed method adopts the grey system theory, which is regarded as one of the methods to handle insufficient information, to establish a fire safety ranking evaluation framework.