DES MOINES (AP) - More than half of Iowa college students living in dormitories don't have fire suppression sprinkler systems in their buildings, according to a newspaper survey.

Nearly 30 colleges and universities in Iowa with dorms have spotty records of installing the systems. That's partly because they're more expensive than fire alarms, and party because state law doesn't require the sprinklers in older campus living spaces, according to a copyright story in the Des Moines Sunday Register.

Fifty-seven percent of students living in campus housing live in buildings that don't have sprinklers, while the newspaper's survey said 43 percent are protected by fire-safety systems. The survey looked only at dormitories that are operated by the schools. It did not include fraternities, sororities or off-campus apartments that the schools do not control.

Recent high-profile fire tragedies at universities that didn't have sprinkler systems have prompted schools throughout the nation to look into installing sprinkler systems.

For example, millions of dollars are being used to install the systems in the remainder of residence halls at Iowa State University and Drake University. In Ames, home to ISU, city officials are pushing private fraternity and sorority houses to install the sprinkler equipment.

"We've seen that too many times across the nation where a student lost his life because a chapter hall or residence hall did not have a fire suppression system," said Jason Pierce, the University of Iowa's adviser to fraternities and sororities in Iowa City. "It's just not worth it."

The Register's examination found that five private school campuses in Iowa don't have sprinkler systems in their residence halls. Those include: AIB College of Business in Des Moines, Briar Cliff University in Sioux City, Graceland University in Lamoni, Maharishi University of Management in Fairfield and Waldorf College in Forest City. At Maharishi University, officials say they plan to build new residence halls and housing in three or four years, and that those buildings will have sprinklers.

Other colleges have sprinkler systems in all of their dorms, including Allen College in Waterloo, Grinnell College in Grinnell and Loras College in Dubuque.

Among Iowa's three state universities, the University of Northern Iowa in Cedar Falls has the poorest record of installing sprinklers. Only one of its 10 residence halls being equipped with sprinklers, and only 6 percent of UNI's students who live in campus housing are in buildings with sprinklers, according to the survey.

Six of 11 of the University of Iowa's on-campus residence facilities are equipped with sprinklers, covering 43 percent of dorm-dwelling students. At Iowa State University, half of the campus residence halls have sprinklers, and 54 percent of students living on campus are in sprinkler-protected residence halls.

Officials say it can be expensive to retrofit older buildings with the systems, and a national organization that sets the agenda for fire codes says only that they should be part of new construction.

"When you start retrofitting buildings, it opens up an entirely new set of issues," said Jim Tidwell of the International Code Council in Washington, D.C. "Some of the buildings might have asbestos," which he said would double or triple the cost of a renovation.

"We don't like to talk about costs versus safety," he said. "The fact is, many of these facilities would simply have to be torn down."

Ron Humphrey is a fire prevention supervisor at the state fire marshal's office. He said a new set of fire regulations adopted this year in Iowa strengthens the requirements for sprinklers when new residence halls are built. It requires the devices, regardless of the type of construction or size of the building, he said.