Bowtie analysis for risk assessment of confined space at sewerage construction project

This paper aims to investigate the issues related to safety in confined space at the sewerage treatment plant construction project in the Hulu Langat district and to provide a solution by proposing a substantial approach to mitigating risk during confined space entry due to an ineffective risk assessment and poor compliance by project management. The methods used were site visit observation and survey, followed by an analysis of the selected risk assessment method. The site visit to the sewerage treatment plant project investigated the compliance of confined space risk assessment documents to established requirements such as OSHA 1994, FMA 1967, ICOP 2010, HIRARC Guidelines 2008, Quebec Regulation 2015, ISO 31010, HSE UK, and BCGA UK. The selected risk assessment method was analyzed with Bowtie Risk Assessment by referring to the preventive approach concept or barrier analysis. Next, additional information relevant to risk assessment from journals was included. Evaluation of Bowtie Risk Assessment was conducted through a focus group discussion (FGD), which plays an essential role in developing the Bowtie risk assessment graphical framework. The proposed Bowtie Risk Assessment graphical framework provides a sewerage treatment plant construction project with a holistic technique for preventing confined space accidents. It also provides a safe work system, manages hazards and risks effectively, promotes good leadership practices, improves company reputation, and significantly reduces accident costs. The framework is also helpful as a reference model for other industry players.