The effect of an active lumbar system on the seating comfort of officers in police fleet vehicles.

The purposes of this study were to determine which seat features/occupational demands contributed to police officer discomfort and whether an automobile seat fitted with an active lumbar system (ALS) could reduce driving discomfort. Fifty-eight officers were given questionnaires to assess driving discomfort. High discomfort levels were associated with computer use, duty belt, sidearm/radio, body armour and lumbar support interface. Discomfort was highest in the lumbar, sacrum, upper pelvis and mid-back regions. Twelve officers spent one shift each in a police vehicle seat and an ALS seat. Discomfort was assessed every 2 h during 8-h shifts. Reduced discomfort was reported with the ALS seat. Three lumbar support features, the duty belt, and the lumbar and right upper pelvis regions, showed reduced discomfort. Overall seat discomfort decreased by 47% after 8 h of exposure to the ALS. Modifying the automobile seat helps to reduce officer discomfort during prolonged vehicle usage.