Operating performance of passive infrared counters under different seasons

Abstract

This research analyzes the operating performance of two commercially available passive infrared counters (PICs) of pedestrians as a function of site, summer, fall and winter seasons in terms of counter sensitivity. Three sites were selected for field analysis in Winnipeg, Canada. Based on a sample of 24,690 people counted by the two PICs from July 2014 to February 2015, this research found that with a 95 percent confidence, Eco-Counter’s sensitivity ranged from 73 to 97 percent while TRAFCO’s ranged from 57 to 97 percent related to people occlusion. On weekdays, Eco-Counter’s absolute error was 16 percent and TRAFCO’s was 18 percent. On weekends, Eco-Counter’s absolute error was 18 percent and TRAFCO’s was 21 percent. In addition to people occlusion, site, seasons, and time of week (weekday and weekend) were found to affect the operating performance of the PICs. Correction factors were also calculated per counter, site, and seasons.