Development of a Framework for Risk Assessment in Building Demolition Works

Abstract

The demolition process in construction projects is risky and involves many hazards that may lead to several accidents ranging from minor injury to fatality. These hazardous activities impose risk to contractors, employers and workers, and the public. Nowadays, these demolition operations are increasing in every corner of India because of redevelopment policies, new bylaws, outdated design, and aging of buildings and habitation facilities to accommodate the increasing population in the limited land area. Still, in most places, demolition operations depend on contractors’ knowledge without following any proper standard or framework. Therefore, this study attempts to develop a framework for risk assessment in the demolition of buildings that involves three phases: identifying, assessing, and giving control measures to potential hazards. In this direction, this study identified 40 potential hazards with the help of existing literature, field survey, and expert interviews; and categorized them into seven categories. For assessment, the standard 5×5 risk matrix methodology of the British Standard 8800:2004 is used, which gives the risk value to each hazard, thereby categorizing the hazard with respect to the level of acceptance. The Relative Importance Index (RII) method is then used for ranking the identified risks. Considering the obtained likelihood and severity of each hazard, fall from height and noise pollution are identified as the most and least significant hazards, respectively. Finally, control measures are suggested. The outcome of this study shows the priority order of demolition hazards from major to minor. It gives an idea to demolition practitioners for which hazard has to be eliminated or mitigated primarily with their respective control measures. It also benefits policymakers to formulate a policy or law on demolition safety.