Elevator availability and its impact on stair use in a workplace
Consistent success in encouraging stair climbing on public access staircases contrasts with equivocal evidence for effectiveness in worksites. This paper tests whether contextual factors may affect stair/elevator choice. The study investigated the impact of elevator availability, pedestrian traffic (number using the elevator and stairs per minute), building occupancy (total individuals in the building) and time of day on stair ascent and descent in a workplace. Stair and elevator choices were monitored by automatic counters every weekday during two phases. In a natural experiment, days with four available elevators were compared with days when three elevators were available. Stair use increased for three elevators compared to four. Increasing building occupancy was associated with increased stair use, whilst increasing pedestrian traffic and time of day was associated with reduced stair use. A follow-up study revealed complimentary effects of building occupancy and time of day on elevator waiting times, indicating that increased stair use by contextual factors reflects increased elevator waiting times. In contrast, shorter waiting times are likely when momentary pedestrian traffic is high and later in the day. Crucially, the magnitude of the effects of these contextual factors was ten times larger than previously reported effects of stair climbing interventions. ?? 2011 Elsevier Ltd.