BC: Photo Radar and Posted Speed Limits...Superintendent John G. Bodinnar, Director, Victoria Police Traffic Camera Office, Melbourne, Australia. Securing Road Safety through Synergy, Perception and Images. International Traffic Safety Organization, 6th World Congress, 1994 October 3-6. p.17.
"Speed camera enforcement locations... will be subject to speed zone confirmation by VicRoads prior to further enforcement when more than 10% of (200 or more) vehicles are detected speeding."
FHWA Study Tour for Speed Management and Enforcement Technology, 1995 December, p. 48.
"In the vast majority of cases, the program [NLIMITS and VLIMITS, used to set speed limits in Victoria, Australia] recommends a speed limit within 5 km/h of the 85th percentile speed."
In Victoria, Australia, speed limits will be confirmed by a qualified engineer if more than 10% of the traffic exceeds their speed tolerance of 10 km/h. Speed limits in Victoria generally align with the 85th percentile speed.
Province of British Columbia, Motor Vehicle Branch. News Release July 26, 1996.
"If the 85th percentile is higher than 19 km/h over the posted speed limit, police will not use photo radar at the site until the municipality or Ministry of Transportation and Highways (depending upon jurisdiction) reviews the posted speed limit."
In BC, 15% of traffic (the 85th percentile) must exceed the posted speed limit by 19 km/h in order to get a review at the speed limit. So while Victoria, Australia, has speed limits set to within 5 km/h of the 85th percentile, we don't even merit a review unless our speed limits are over 19 km/h from the 85th percentile.
Province of British Columbia, Motor Vehicle Branch. Backgrounder June 21, 1996.
"Photo radar police evaluate the proposed sites according to strict operating guidelines:... Speed limits are reviewed first."
Integrated Traffic Camera Unit. Photo Radar Project: Questions and Answers. Handout, p. 1, dated 96-07-03:
"Speed zones selected by communities can be evaluated but this does not mean that all speed zones will be reviewed."
So much for the strict operating guidelines!
Mike Kawczynski. "Speed-Flow Relationships on Rural Roads in British Columbia - Appendix." Victoria, 1994. - From calculations of data generated.
On British Columbia rural highways, speed limits typically align with the 30th percentile: on average, 70 per cent of drivers are technically speeding.