On March 3, 1994, at 1845 Pacific standard time, a Cessna 150H, N22682, was involved in a propeller strike to a person on the ground while deplaning a passenger at Sacramento, California. The aircraft was owned and operated by the pilot and was on a local area pleasure flight conducted under 14 CFR Part 91. Visual meteorological conditions prevailed at the time, and no flight plan had been filed for the operation. The certificated private pilot and her deplaned passenger were not injured; however, another person on the ground was injured as she ran toward the aircraft and into the turning propeller. The flight originated on the day of the mishap at about 1500 from the Rio Linda Airport. In a verbal statement, the pilot reported that she had just returned from a flight and had taxied to a point on the ramp where she had arranged to deplane her passenger, a 12 year-old child, with the assistance of an adult escort. The aircraft's engine was at idle with the propeller rotating at about 800 rpm's during the deplaning operation. As she watched her passenger deplane, she happened to glance toward the front of the aircraft in time to see a second child running toward the aircraft. Before she could shut down the engine, the child was struck by the propeller. The child had been instructed previously not to approach the aircraft without an adult escort. The propeller strike caused serious injuries to the child, but no damage to the aircraft.