More than half of the commercial vehicles examined during a three-day Calgary police inspection were ordered out of service after inspectors discovered critical safety defects.The Calgary Police Service said 197 commercial vehicles were inspected from Sept. 15 to 17 in high-volume traffic areas around the city.Of those, 100 vehicles — 51% — had critical defects serious enough to place them out of service.Another 36 vehicles, or 18%, had major defects requiring attention, while 61 vehicles, or 31%, passed without critical defects.Inspectors issued 98 violation tickets during the operation. One driver was also charged with operating a commercial vehicle without a valid licence.Police said some of the most common problems included worn tires, improperly secured cargo and inadequate brakes.Inspectors also discovered defective headlights, faulty steering systems and leaking fuel tanks.“Commercial vehicle drivers perform a critical service for Calgarians, transporting important goods we all rely on,” said Calgary Police Traffic Unit Insp. Robert Patterson.“However, it’s critical that those vehicles meet all legal standards to ensure the safety of everyone on the road.”.The 51% out-of-service rate was higher than the 48% recorded during Calgary's spring commercial vehicle inspection.The operation was conducted with Sheriff Highway Patrol, Alberta Transportation Vehicle Safety and Economic Corridors, Airdrie Bylaw and the City of Calgary.Inspectors use the North American Standard Out-of-Service Criteria to determine whether safety violations are serious enough to prevent a commercial vehicle or driver from continuing to operate until the problem is corrected.