The behaviour-based approach has been widely used to develop interventions for construction accident
prevention. The actual effects of such interventions, however, often do not meet expectation or have only
a short-term effect. Recent studies look beyond the immediate accident circumstances to shed light on
systemic factors that lead to accidents. The authors present an institutional analysis of construction accident
causality through investigation of heat illness cases on construction sites. Heat illness is a special
type of incident in which the individual is both the victim and, to a certain extent, the agent. Its consequence
can be fatal, but its spread to uninvolved personnel is limited. Like other construction accidents, it
affects individuals but cannot be effectively managed without addressing the risks embedded in the institutional
environment of the system in which the individual is situated. This provides a simplified event
for identifying institutional factors affecting construction accident causation at different systems levels in
construction projects. The analysis is based on 216 individual construction workers’ cases from 29 construction
sites, including 36 reported critical incidents of heat illness cases. These are triangulated with
data from site observation, interviews with managers and field notes of stakeholders’ meetings.
Institutional factors that contribute to proactive and reactive behavioural intervention of heat illness
development are identified at eight levels of systems. The findings can be used in guiding accident investigation,
developing effective interventions and identifying improvement opportunities for stakeholders
at different levels of systems related to a construction project.