The use of Lifts for Emergency Evacuation - A Reliability Study

Vertical egress from high-rise buildings is a challenge for occupants with mobility impairments. Past research indicates that use of lifts is a feasible option to supplement conventional stair evacuation. There is however one facet of lift evacuation that has limited available data, that is lift reliability. This research investigates lift reliability through a sample of 81 general passenger lifts in service throughout Australia. The sample period was over the past three years. Lift service records were used to ascertain the downtime due to various faults and maintenance. Statistical analyses of the raw data were conducted to obtain the reliability and its probability distribution. The average reliability of lifts was found to be 0.993. This result was compared with that obtained by others in the past.