Despite the improvement of digital technologies (e.g., building information modeling) in enhancing construction safety management, human factor–related issues such as individual perceptions, attitudes, and behavior in safety cannot be downplayed. Existing studies have adopted safety management approaches that address human-factor issues by defining safety climate. From safety climate research, it is evident that certain demographics or subgroup factors can significantly affect safety management. This study aimed to investigate how individual perceptions of safety hazards would be affected by the given hazard’s own feature (e.g., probability of occurrence). In addition, the study explored the impacts of subgroup demographic factors (e.g., job position and experience level) on safety perceptions. Eight commonly encountered site hazard/accident scenes were predefined according to their occurrence, severity, and visibility. A site survey approach was adopted to investigate how construction employees from different demographic subgroups rated the degree of danger of the eight predefined scenes. The follow-up statistical analysis revealed that (1) a hazard/accident scene with higher occurrence and lower severity caused a higher variation among employees’ opinions in perceiving its degree of danger; (2) entry-level employees tended to evaluate hazards with a higher degree of danger; and (3) compared to early career employees and senior peers, the mid-career professionals tended to perceive a lower degree of danger of a given hazard/accident scene. This study contributed to the body of knowledge in construction safety by investigating the effects of the given hazard/accident’s feature (e.g., occurrence) in employees’ perceptions, as well as integrating different scenes of safety hazards in the subgroup analysis based on employees’ job duties or work trades and their experience levels. Future research is also recommended to address individuals’ safety perceptions and demographic factors in safety management.

There have been limited studies analyzing the causes of construction workers’ unsafe behaviour from the social psychology perspective. Based on a Grounded Theory approach, this study first identified and defined seven coded categories related to workers’ dangerous behaviour on construction sites. The original qualitative data were obtained from individual site interviews conducted with 35 construction professionals. These main categories were found connected to workers’ status of safety awareness and sense of danger, which affected the type of unsafe behaviours, i.e., proactive, passive, or reactive behaviour. By further integrating social cognitive psychology theories into workers’ behavioural decision-making process, the formation mechanism framework and diagram were developed to describe construction workers’ unsafe behaviours based on the dynamic process of balancing the individual desires and perceived safety risks. This study advances the body of knowledge in construction safety behavioural management by performing in-depth theoretical analysis regarding workers’ internal desires, activated by external scenarios and intervened by a personal safety cognition system, which could result in different motivations and various behavioural outcomes. It is argued that safety cognition serves as a mediated moderation system affecting behavioural performance. Practical suggestions on developing a proper safety management system incorporating safety education in guiding construction workers’ site behaviours are presented.