Kathy Layo's job at UPMC Passavant, McCandless is that of part-time respiratory therapist, but her calling is that of volunteer singer to the hospital's patients.

At least one off-day each week, the 45-year-old Hampton woman returns to the sprawling medical center and roams the halls asking patients if they'd like her to sing to them. She also comes back -- "I try to do it within 24 hours" -- for special requests that patients can file with volunteer services.

But, she said, during a recent day of singing, "I do the bulk of my singing when it just brings me into someone's room. It seems like fate."

She calls her program, which she began in November 1999, "Singspiration," and describes it as "very spiritual for me. I feel the Holy Spirit leaves me when I sing to these patients."

It often is very spiritual for her one-person audiences as well. That seemed to be the case when Ms. Layo sang "A Cockeyed Optimist" from "South Pacific" to Carol Weber, 71, of Wexford, who described herself as suffering from "a lot of major things."

"That makes me feel good," Mrs. Weber said after Ms. Layo finished.

"I've been in the room and seen people crying when she left," said Diane Gloor, head of volunteer services. "[Patients have] spiritual and emotional needs. It's not just physical needs. We try to give them whatever else can make them feel better and for some it's song."

A teenager, Jessica Hartman, of Allison Park, also began doing some singing at Passavant in June.

"I think it gives them a relief from what they're going through," Ms. Layo said. "It's a break in the day. It can break up the monotony. It can touch a part of them that hasn't been touched in a long time. I have patients tell me stories from a long time ago.

"I've seen the spirit soar when the body is unable to move, like weak and unable to move. That's the neatest thing in the world to do that."

Ms. Layo, who has sung all her life and took two years of voice lessons in high school, was working for the defunct Central Medical Pavilion when she got the idea for "Singspiration." It came after someone asked her to sing to a nurse who was dying of cancer. "I said 'I will if you'll sing with me,' " Ms. Layo said. The duo sang the Irish hymn "Be Thou My Vision."

"I thought it might be a wonderful service to offer patients," she said. When she moved over to work at Passavant she broached the idea to the administration, which gave her the go-ahead.

Since then she has sung to more than 4,200 patients in a rich voice deeper than the typical alto. She has sung for wedding anniversaries celebrated in hospital rooms and at one wedding. "It was under sad circumstances," Ms. Layo said. "The bride was in hospice."

She estimates the size of her repertoire, which in the beginning comprised only hymns, at more than 100 songs. She still does hymns -- "The two most popular are 'Amazing Grace' and 'How Great Thou Art' " -- but show tunes also are well-liked.

That was the case when Ms. Layo was invited into the fifth-floor room of Joyce Bogolea, 66, of Harmony, who was recuperating from a broken hip and who told the singer to pick something from Broadway.

Ms. Layo sang the hauntingly beautiful "What I Did for Love" out of "A Chorus Line."

Afterward, Ms. Bogolea smiled and clapped. "Oh, how nice. I love music and I love the Broadway shows." She reminisced a bit about how her brother used to give her tickets to the top New York musicals when he was connected to the business. "I saw ['A Chorus Line'] in the front row," she said.

Ms. Layo turned to "Edelweiss" from "The Sound of Music" when Carl Persic, 60, of Hampton, who was hospitalized with a ruptured back disc, invited her in to sing.

Mr. Persic also applauded.

"That was sweet," he said. "What a lovely thing in the morning."

For Ms. Layo, too. "I'm passionate about it," she said, "because I think it's what I'm supposed to be doing."