Trench excavation health and safety in South African construction

Abstract

Construction work is hazardous by nature, and trench excavation collapses contribute to the disproportionate number of fatalities and injuries in construction. A quantitative study was conducted in South Africa to produce a framework of interventions to enhance excavation health and safety (H&S) and mitigate excavation related injuries and fatalities. A selfadministered questionnaire was circulated among a sample stratum comprising construction supervisors, H&S Officers, design engineers, and construction managers. The salient findings include: a range of factors that contribute to excavation incidents; excavation hazard identification and risk assessment (HIRA) is important relative to a range of excavation-related hazards; a range of key excavation aspects are not addressed between a near major to major/major extent, and trench collapses impact primarily in the form of fatalities and other injuries, but also impact on performance relative to the other performance parameters. Conclusions include: a cocktail of interventions are necessary to mitigate excavation incidents; there is a need for enhanced supervision during excavations and enhanced excavation H&S knowledge and training; excavation H&S inspections are not effective, and trench collapses have a major as opposed to a minor impact. Recommendations include: an appropriate excavation H&S qualification and training should be developed and registered in terms of the National Qualifications Framework Act, 2000; employer associations should raise the level of awareness concerning excavation H&S; excavation H&S inspections must be comprehensive, and contractors should conduct detailed cost-benefit, and cost of accidents analyses relative to excavations.