The effects of three environmental factors on problem-solving abilities during evacuation

To escape a dangerous building emergency occupants may need to respond quickly, assess the environment, plan their actions and tackle possible problems during evacuation. In this study 147 participants were tested in an experimental evacuation design for the effects of three environmental factors (fire alarm, lighting and emergency exit signs illumination) on problem-solving abilities. The experimental evacuation scenarios consisted of: (1) fire alarm, normal lighting conditions and illuminated emergency exit signs, (2) fire alarm, dark environment and illuminated emergency exit signs and (3) fire alarm, dark environment and not illuminated emergency exit signs. The tested problem-solving abilities were the time to plan actions and number of excess moves on the Tower of London test. The main results indicate that the third experimental evacuation scenario led to a decrease of 25.9% in planning time, compared to the control scenario. Age also had a significant effect on planning time. The oldest participants took or needed on average 42 s more planning time than the youngest participants, an increase of 146.9%. Furthermore, the second and third experimental evacuation scenario led to significant more excess moves, compared to the control scenario. However, the older the participants the less excess moves they had. For gender no significant effects on problem-solving abilities were found. In addition, the relationships between problem-solving abilities and building evacuation time were investigated. Longer planning times were associated with longer evacuation times and more excess moves were associated with shorter evacuation times. Practical implications for building and safety managers are to add training in darkness or assume more evacuation time in darkness or for older aged populations in evacuation plans and drills. Future research should collect more quantitative data about effects of various environmental factors and personal characteristics, such as problem-solving styles, age and gender, on building evacuation behaviour.