On May 17, 1998, at 1600 hours Pacific daylight time, a Cessna 172A, N7222T, owned and operated by the pilot, collided with the airport's perimeter boundary fence while taxiing for takeoff at the Van Nuys Airport, Van Nuys, California. The airplane was substantially damaged, and the private pilot was not injured. The flight was originating at the time of the accident. Visual meteorological conditions prevailed at the time of the personal flight, and no flight plan was filed. The pilot verbally reported that he had received a ground control clearance to taxi for takeoff from his transient position near the northeast side of the airport to the beginning of runway 16L. He proceeded slowly in a northerly direction and became somewhat confused regarding the route to take approaching an area under construction. The pilot indicated that he diverted his attention toward the active runway, entered a vehicle service road in lieu of the taxiway, and while proceeding toward the runway the airplane's right wing collided with a fence pole. In the pilot's completed report he indicated that prior to the mishap he had flown with his flight instructor to finish the fourth phase of the Federal Aviation Administration's (FAA) Wings Program. During his lesson he had performed at least one takeoff and landing, and taxied on both a taxiway and a service road. The accident occurred following the dual instruction as he was attempting to return to his home base at the Whiteman Airport. In the pilot's report, he described the sequence of events leading up to the accident in the following manner: "After letting the instructor off I taxied toward the taxi-way to depart for Whiteman after contacting the tower. Upon nearing the taxi-way, I stopped to observe the situation. I noticed the taxi-way marked with black lines both to the right and to the left, the left taxi-way was also barricaded. The right side was only marked in black, therefore, I decided to use the service road to get to 16L since I had to use (the) service road to the south of this area earlier. As I started for the service road, I heard a loud noise and the aircraft veered to the right." On June 5, a representative from the Safety and Standards Branch in the FAA's Western-Pacific Regional Office (AWP-620) accompanied the Safety Board's Investigator-in-Charge and a representative from the Van Nuys Airport manager's office to perform an on-site inspection of the accident site area. The purpose of the inspection was to ascertain the degree of the municipal airport's conformity with Advisory Circular 150/5340-1G, Standards for Airport Markings. The FAA representative reported that in the vicinity of the barricaded area where the pilot reported he had previously taxied, there was no taxiway centerline marking on the Taxiway E detour from Taxiway 5D onto the airport service road and then onto Taxiway 4D. There was a continuous taxiway centerline marking on Taxiway 4D that continued northbound onto Taxiway E, which was the route that the pilot was cleared to utilize. The airport management indicated that although the airport's markings complied with the advisory circular in the accident site area, to enhance safety it would increase the conspicuity of the taxiway/access road markings near the accident intersection. Management would extend the solid taxiway edge line across the service road that the pilot erroneously used, and it would paint dashed taxiway edge lines across the tenant leasehold along the north side of taxiway 4D.