SALT LAKE CITY (AP) _ A former director of an arena where three teen-age fans were trampled at a concert by the rock band AC-DC said the switch from reserved seating to general festival seating took ''every safety consideration'' into account.

But minutes of a meeting indicate that at least part of the reason for the switch was because the arena was losing money on broken chairs, a newspaper reported Saturday.

Two 14-year-old boys and a 19-year-old woman died after they were pinned at the bottom of a pile of fans who rushed the stage during the opening minutes of the Jan. 18 show at Salt Lake Palace.

Salt Lake County and Spectacor Management Systems, which operates the county-owned arena, have discontinued festival seating until an investigation is completed.

Festival seating, general admission rather than assigned seats for ticketholders, has been outlawed in several cities. In 1979, 11 people were killed and 22 injured in a rush of fans outside Cincinnati's Riverfront Coliseum at a general admission concert by the Who.

Sam Driggs, a former Salt Palace director who now heads a convention center in Austin, Texas, said his decision to begin festival seating in the spring of 1988 was not made lightly.

''When we started festival seating it was done only after thoroughly examining every safety consideration,'' he said. ''It was not an overnight decision.''

Salt Palace officials attended a concert in Tucson, Ariz., in 1988 that had festival seating but used large cement cones to break up the crowd. Driggs said the county bought similar cones shortly afterward and those are in place.

Driggs contended that festival seating is not dangerous as long as security is tight. However, concertgoers can be injured by standing on seats or moving them into the aisles, he said.

Officials have been examining minutes from Salt Palace Advisory Board meetings to find references to the decision to switch to festival seating. But Driggs said the decision may have been made internally, without approval from any board.

The Deseret News reported Saturday that it has obtained minutes dated May 24, 1988, from a meeting of a business group and others who advised Salt Lake County.

At the meeting, arena officials made a presentation on ''the change ... from reserved seating to festival seating,'' the newspaper said. The officials did raise safety concerns but also pointed out that ''at the last concert there were 64 chairs damaged from kids standing on them, at a cost of $80 each.''

The officials said broken chairs can be dangerous for concertgoers and said 15 to 20 people usually were injured at each concert regardless of seating, mostly from heat exhaustion, the newspaper reported.

Meanwhile, Salt Lake officials said they were discussing ways of improving communication with groups playing at the arena and using the media to get the message across about proper behavior at concerts.

''All of the security in the world cannot avert a situation if you do not have the full cooperation of the audience,'' said Stephen Greenberg, vice president of productions for Spectacor Management Systems.