Finding the Probability of Doors Being Open Using a Continuous Position Logger

Data for the probability that a doors are open or closed in the event of a fire is sparse. The literature only presents a snap-shot rather than how the position of the door has changed over time. This paper describes the development of a low-cost, unobtrusive logging device that can continuously monitor the position of a door for extended periods. The devices were used to record 180 days of data from 52 doors located in different types of sleeping occupancies: hotels, apartments, dormitories and rest homes. Results were obtained for the probability that doors were open during day-time and night-time; and also during weekdays and weekends. Overall a probability distribution for the fraction of time that a door was found to be open is an inverse Gaussian function with mean µ = 0.104 and shape factor l = 0.0117.