Evacuation models commonly employ pseudorandom sampling from distributions to represent the variability of human behaviour in the evacuation process, otherwise referred to as ‘behavioural uncertainty’. This paper presents a method based on functional analysis and inferential statistics to study the convergence of probabilistic evacuation model results to inform deciding how many repeat simulation runs are required for a given scenario. Compared to existing approaches which typically focus on measuring variance in evacuation times, the proposed method utilises multifactor variance to assess the convergence of a range of different evacuation model outputs, referred to as factors. The factors include crowd density, flowrates, occupant locations, exit usage, and queuing times. These factors were selected as they represent a range of means to assess variance in evacuation dynamics between repeat simulation runs and can be found in most evacuation models. The application of the method (along with a tool developed for its implementation) is demonstrated through two case studies. The first case study consists of an analysis of convergence in evacuation simulation results for a building including 1855 occupants. The second case study is a simple verification test aimed at demonstrating the capabilities of the method. Results from the case studies suggest that multifactor variance assessment provides a more holistic assessment of the variance in evacuation dynamics and results provided by an evacuation model compared to existing methods which adopt single factor analysis. This provides increased confidence in determining an appropriate number of repeat simulation runs to ensure key evacuation dynamics and results which may be influenced by pseudorandom sampling are represented.

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Traditional fire alarms emit a high-frequency sound to alert the occupants of an imminent threat, which may be less appropriate for people who are deaf or hard of hearing. To address this issue, the scientific literature concerning alternative alarm technologies has been reviewed to evaluate their effectiveness in awakening people who are deaf or hard of hearing. The results show that low-frequency alarms, bed shakers and/or pillow shakers seem to be the most reliable existing technologies for this group of people. The main codes and standards relevant to these technologies have also been screened. This highlighted that a new standard for alarm technologies incorporating tactile signals might be needed. In addition, this paper presents the responses of 36 people who were deaf or hard of hearing participating to a survey in which their experiences and preferences in relation to fire alarm technologies were investigated. While some technologies have been identified in the literature as potentially effective, the survey responses indicate that people who are deaf or hard of hearing do not necessarily use them.

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