Paramount Parks reopened Kings Dominion's Shockwave roller coaster in Virginia and similar rides at two other amusement parks yesterday as authorities portrayed Monday's fatal accident on the Shockwave as strictly the fault of its 20-year-old victim.

Park officials and authorities for Hanover County, where the park is located, said the stand-up roller coaster and its double-harness safety system performed properly. A preliminary report by the county sheriff's office yesterday blamed "the rider's failure to follow the proper safety instructions."

Authorities portrayed the victim, Timothy Fan of Long Island City, N.Y., as reckless in wriggling free of the shoulder harness in defiance of park rules and common sense. He flew out of the train when it hit a final curve at 40 mph and died of blunt force trauma to the head after hitting a steel catwalk, authorities said.

A lawyer for Fan's family objected to that portrayal of Fan, a student at New York's Hunter College who was looking forward to a career in social work. The lawyer, Gary A. Tomei of New York City, called the official pronouncements about the accident "self-serving nonsense."

While Paramount Parks officials reopened the stand-up roller coasters, they kept four Drop Zone rides closed at parks across North America, as police in Santa Clara, Calif., tried to determine how a 12-year-old disabled boy came free from a harness on that ride and fell to his death on Sunday. The fatal accidents have turned new attention to the safety of amusement parks.

In Virginia, authorities and park officials piled on evidence of Fan's alleged misconduct today and allowed reporters to ride in the spot on the Shockwave train from which Fan fell.

"The restraints themselves are safety restraints. They aren't meant to capture you," said Capt. David Hines of the sheriff's office. "Mr. Fan was there apparently to have a good time. He did not abide by the safety rules."

Hines said a sheriff's deputy managed to pull himself free from the Shockwave's shoulder harness during tests on Wednesday, but only with great difficulty. He said that the deputy was larger than Fan, who was an estimated 5-feet-4 and 140 pounds, but that even a smaller man could get out of the harness only with "a concerted effort."

Chance Hester, the park's safety manager, said a friend of Fan's was riding to Fan's left. He told park officials he saw Fan wriggle free of the shoulder restraint.

"There is no way that he would have come out of the train if he had remained in the restraint system," Hester said.

Hines said there is no evidence that Fan intended to harm himself, nor is there evidence that he was intoxicated. He was injured during his second trip on the ride, the sheriff's office said.

Park officials said that prior to Monday's accident, 13 million guests had ridden the Shockwave without a serious injury or death since it opened in 1986. The two-minute ride climbs 95 feet in the air before plunging the train's 24 standing riders through a steep vertical loop and a sideways spiral before returning to the station.

Fan was thrown from his train during one of the ride's tamer moments. Before the turn where he was ejected, the slowing train goes through a straightaway.

After the final turn, the ride comes to a temporary stop at a waiting area before looping back into the station.

Hanover County building inspectors, who oversee safety at Kings Dominion, said they found no problems with the ride.

Several riders said yesterday that they could not understand how Fan freed himself from the restraints. "I don't understand how someone could have died on this," said one woman, out of breath as the ride ended. "That wasn't bad at all."

The dual restraints that operate on the Shockwave are unique to stand-up roller coasters. They consist of a lap bar and a pair of shoulder "wing" harnesses that swing in toward a rider's chest and lock into place. As part of the park's standard procedures, a pair of ride operators adjust the harness mechanism for each rider and then check each harness.

Hester said that once the train has left the station, the shoulder harness cannot be moved outward, but it can be tightened if pulled toward the rider's chest. Park officials said Fan's harness was securely fastened when the train pulled into the station.

Fan was traveling with a New York tour group that specializes in trips for Asian Americans, running regular trips to Kings Dominion.

Representatives of Fan's family called him responsible, thoughtful and a source of pride for his sisters, 13 and 17.

Gary Leong, the manager at a Manhattan porcelain shop where Fan worked, said: "When I read in the papers what [authorities] are saying, it's just amazing . . . . I don't think he's that dumb."

Tomei, the lawyer, blasted the conclusions of park officials and county authorities. "What are they going to say?" he asked. " 'We did it? We're responsible? Don't take our ride?' "

In California, investigations into the death of the 12-year-old boy continued. Paramount's Drop Zone rides pull guests more than 200 feet in the air, then drop them at speeds reaching 62 mph before brakes slow them.

Sgt. Anton Morec of the Santa Clara Police Department said investigators are working on three theories in the boy's death: either a mechanical malfunction caused his harness to fail; his harness was not secure; or the boy's behavior somehow led to his fall.

Morec said a preliminary inspection of the ride showed no "overt evidence that the ride malfunctioned," adding that it could be weeks before police are able to determine why the boy fell.

That accident has added urgency to calls in California for state regulation of amusement parks. Assemblyman Tom Torlakson, a Democrat, is pushing that issue in the California legislature.

But, Torlakson said, "It's a relatively safe industry if you look at the number of injuries per rides."