Tim Doyle isn't afraid of ghosts. He recalls with vivid detail several mysterious events he said he experienced while working as a graphic artist at Sign Creators Inc., a sign manufacturer in the former Walnut Street Elementary School in West Homestead.

"I wasn't scared, but I did get the chills," he said.

Mr. Doyle, of Homestead Park, recalled that the former classroom he used as an office would suddenly get cold.

"And then I saw a girl all dressed in white. It was like a First Communion dress. She never talked to me," he said.

He also recalled retrieving his watch after working on a sign with strange results.

"I touched it, and it was so cold it was like icicles," Mr. Doyle said.

Mr. Doyle, 70, has since retired. But last Saturday, he related his experiences to Jim Matthews, a paranormal investigator, as the two stood in the spot where he said the events occurred.

Mr. Matthews, 37, of West Mifflin, led a team of more than a dozen other investigators from Greater Pittsburgh Paranormal Society on a search for paranormal activity at the former school.

The all-night investigation was an orchestrated event with seven lights-out sessions, requiring miles of electrical cord, laptop computers, 12 cameras equipped with night vision, several motion detectors, digital voice recorders and hand-held cameras.

"This is one of our larger investigations," Mr. Matthews said.

Teams of two rotated to designated "hot spots" throughout the building in half-hour intervals. Each recorded and took notes in silence. Hot spots were determined through anecdotal evidence collected in two preliminary site visits.

"But we don't tell the investigators all the stories, so they won't be influenced," Mr. Matthews said.

"And we try to debunk all claims before an investigation. There are a lot of environmental factors that can explain certain things," Mr. Matthews said.

Matt Sedlak, 28, of Munhall, can't rationally explain what he has seen while working as a production artist for Sign Creators.

"I saw a person walk right through a wall," he said.

Mr. Sedlak was familiar with the stories about ghosts at the former school, having grown up in the area. But seeing is believing. Some speculate the school janitor, nicknamed Shorty, is the one who appeared to Mr. Sedlak and several others.

Dustin Brandt, 24, of Baldwin Borough, grew up playing around the building. His father, Chas Brandt, bought the school more than 30 years ago to house Sign Creators.

"I always heard the stories and was terrified," Dustin Brandt said.

The school's history may have influenced some of the stories. Mr. Brandt described a chalkboard that still bears the signatures of the students and teacher from September 1908, when the school opened.

Team members are all volunteers with varied backgrounds, including prison guards, geologists, government workers and stay-at-home mothers.

"Everybody has their own story about why they're an investigator,' Mr. Matthews said.

Cindy Willoughby, a stay-at-home mother and team investigator from New Castle, was always told she had an overactive imagination as a child.

"The scientific aspect really appealed to me in searching for answers," she said. "I really clicked with this team."

Still, there are a few skeptics on the team, said Rob Hayes, an investigator from the North Side.

"Some things are just beyond our current ability to understand and define," he said. "That's why we do what we do."

Feeling cold is a common report from those who suspect they've experienced paranormal activity. Believers theorize that energy is being drained from surrounding air.

"For anything to manifest, it requires energy," Mr. Hayes said.

He said the team carries extra batteries to all investigations for the same reason.

"Fresh batteries will be dead in minutes or seconds," Mr. Hayes said.

After years of speculation and stories, Mr. Doyle, Mr. Sedlak and Mr. Brandt are among those looking forward to getting possible confirmation from the team about paranormal activity at the site.

The team never charges for services. But, it follows a rigid screening process to prevent wasted time on invalid claims, especially around Halloween.

Following the all-night investigation, team members will analyze their findings and submit individual reports to Mr. Matthews. He will compile a final report including any video or sound evidence and present it to Chas Brandt within several weeks.

The GPPS was founded five years ago. Members conduct both residential and commercial investigations. Members are seeking nonprofit status in order to allow fundraising to help defray the cost of electronic equipment. Currently, the 25 members provide their own equipment for each investigation.

Members went through a rigorous screening process in order to be registered as a member of The Atlantic Paranormal Society family.

This society is featured on the "Ghost Hunters" TV show, airing on Sci-Fi Channel.

"Sometimes people are disappointed when none of the TV ghost hunters show up," Ms. Willoughby said.

According to Mr. Matthews, Pittsburgh has a wealth of paranormal activity.

"You look at the historical background of the city. Anywhere that there is a lot of history, there is likely to be activity," he said.

Mr. Matthews expects to have an interesting report about the Sign Creators investigation in four to six weeks. By the time the investigation wrapped up at 4 a.m. Saturday, many team members had stories to tell.

"We heard voices, footsteps, doors closing and other things," Mr. Matthews said. "Now, we have to correlate that with our video and audio evidence."

For more, visit gpps.proboards.com.

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