Thirty years ago, Joan Pelletier was looking for a job. “There were 30 people in line [for an interview],” she recalled. “I left that and looked at the want ads in my car. I interviewed [at Sonitrol Security Systems of Hartford Inc.], and I didn’t think I got the position.”

One week later, Pelletier got a call from the company. “I thought I would stay a year, but since then I haven’t had an interest in anything else,” she admitted.

Since 1977, Sonitrol, Hartford, Conn., has assisted local police in apprehending more than 140,000 intruders. Joan Pelletier has helped catch her share of them. She has worked all three shifts at some point in her tenure, but Pelletier prefers to work at night.

“Once I worked the day shift for six months,” she remembered. “But the night is more exciting.”

As a central station operator, Pelletier juggles customer calls, monitors customers’ sites and contacts the proper authorities for subscribers in case of an alarm or emergency.

When the pre-amplified microphones placed in subscribers’ buildings detect noises louder than the background noise, Pelletier or another operator is notified and begins monitoring the building. Through a telephone headset, Pelletier can hear everything going on in a subscriber’s building.

She can distinguish among noises such as footsteps, voices and doors. Because Sonitrol’s security system operates silently, intruders do not know they are being heard. Many times they talk, and Pelletier listens.

Once Pelletier heard a scraping noise in a building. She notified the police, but they found nothing and left. She heard the scraping again and called the police. They even brought in a dog, but again found nothing.

Pelletier continued to hear the noise and contacted the authorities a third time. Police found a person hiding on top of a filing cabinet who had been producing the scraping noise by trying to saw off the bars on a nearby window and escape.

Pelletier recalled another memorable incident in a stereo shop. She notified the police of the sound of breaking glass. When police got to the scene, the intruder was gone.

However, he had injured his arm breaking the glass and left a trail of blood in the snow on his way to the hospital, where he was apprehended. The best part of the job, Pelletier maintains, is “catching the criminals.”

Not every situation ends ideally. Pelletier remembered an incident in which a woman who had just come home from the hospital fell asleep with a lit cigarette. Authorities were contacted about the fire, but the woman did not survive.

A few years after Pelletier started working for Sonitrol, a huge disaster struck on Jan. 18, 1978. The Hartford Civic Center’s roof collapsed from the weight of a disastrous snowfall.

Luckily, no one was in the building at the time. But Pelletier heard the collapse and had the authorities at the scene in a flash. “It sounded like an earthquake,” she recalled.

Over the past three decades, Pelletier’s job has not changed, but the technology has. “Joan has seen four generations of monitoring devices,” noted Sonitrol’s president and chief executive officer, Gary LaPlant.

Pelletier maintained that adapting to the changes in technology has been easy, but that the newest technology is a lot better.