Nuclear engineering wasn't just a job for Lawrence Hochreiter, it was a passion.

And so it was that Dr. Hochreiter left an accomplished career at Westinghouse to teach engineering full time at Penn State, where he tirelessly promoted the nuclear engineering program.

It was while teaching a graduate-level reactor engineering class at Penn State on Wednesday that Dr. Hochreiter collapsed. He was pronounced dead shortly afterward at Mount Nittany Medical Center. He was 67.

"It's a huge loss for our department, for the community, for our students," said Karen Thole, head of the department of mechanical and nuclear engineering. "He cared so much. He was just an excellent teacher."

A native of Buffalo, Dr. Hochreiter moved to Pittsburgh after receiving a Ph.D. in nuclear engineering from Purdue University. He worked for Westinghouse from 1971 until 1997, specializing in safety in nuclear power plants.

"He was one of our leading scientists," said Rick Etling, the company's vice president for strategy. "He made sure that whatever we were doing, we were doing safely in the interest of protecting the public."

Dr. Hochreiter left Westinghouse as a consulting engineer -- the highest position for engineers.

While at Westinghouse, he taught at Carnegie Mellon University and Penn State as an adjunct professor.

Given Dr. Hochreiter's focus on the science of engineering, his move into full-time teaching was not a surprise, said Mr. Etling.

"Hundreds and hundreds of students respect Larry for what he's done," he said. "I hear all the time that he was hard, he was driven, and that they're much better people as a result of him."

Though Dr. Hochreiter was notoriously "tough on the outside, boy, on the inside, he was pretty sweet," said Dr. Thole, noting that he was heartened in recent years to see the growth in students choosing nuclear engineering.

He was also proud of an Outstanding Teacher award that he received from Penn State in 2005. At Penn State, he established a distance learning program for a master's degree in nuclear engineering and created a reflood heat-transfer facility, where graduate students could perform experiments.

"You could count on him to have a smile on his face," she said, noting that his car was often the first one in the parking lot every morning. "He really loved what he was doing."

Survivors include his wife of 42 years, Susan, of State College, Centre County; his mother, Margaret Boland Hochreiter MacVicar, of Buffalo; his children, Sarah, of Somerville, N.J., and Paul, of State College; a brother, Gerald, of Brockport, N.Y., and a sister, Marie, of Buffalo.

The family will receive visitors today at the Koch Funeral Home in State College from 2 to 4 and 6 to 8 p.m. A funeral Mass will be held tomorrow at 11 a.m. at St. John's Episcopal Church in Bellefonte.

Contributions can be made to Penn State's department of mechanical and nuclear engineering.