Stimulus Control Techniques Applied to Handicapped-Designated Parking Spaces

The present study evaluated strategies to deter nonhandicapped drivers from parking in handicapped-designated parking spaces. For a 10-day period, a symbol for the handicapped was painted at the front end of the parking spot. During this first phase, violations occurred on 53% of the observations. For the next 4 days, a prominent vertical sign was combined with the ground markings, and no violations occurred during this phase. When the sign was taken down, violations increased to 47% of the observations during this 5-day period. Posting of the vertical sign for the next 5 days decreased violations to 7%. Violations increased to 59% when the vertical sign was removed during the next 4 days. No violations occurred during weekly observations for the sUbsequent six weeks. At a four-month check the sign was still posted, and there were no violations.