System Takes a Bite Out of False Alarms

This nursing facility's analog/addressable fire protection system helps residents stay put and stay safe.

• By Jeff Hendrickson
• Feb 01, 2006

IN the fire alarm industry, there have always been two principal options for fire alarm systems: conventional systems and analog/addressable systems. As you might imagine, there was a time not too long ago when conventional systems were the systems of choice for most buildings. But with changes in technology, costs, perceptions and agency codes, addressable systems have become the norm over the last 10 to 15 years.

The term "conventional" connotes that something is commonly used or done. But this is a term that is extremely time-sensitive. Conventions change; the license to call something "conventional" runs out every few years. The point is, technology is advancing at heretofore unimagined speeds, and it is up to individual buyers to determine whether "conventional" items meet their needs or they need to take advantage of newer technologies that veer from the norm.

Though conventional systems still find refuge in some smaller facilities, it is becoming by and large the job of the newer analog/addressable systems to handle fire control safety for small and large facilities alike. Regardless of the size, however, it's serious business when a fire alarm is activated. Everyone must remain calm. Established procedures must be followed. Response by the appropriate personnel must occur quickly. And, of course, whether or not there is an actual fire emergency must be determined.

A Nursing Home's Fire Protection
With all of these concerns, imagine if the vast majority of the people in the facility are unable to leave the property on their own. The gravity of the situation would be increased exponentially. This is the challenge faced by the Little Sisters of the Poor in Gallup, N.M. Originally created as a private, non-profit, Catholic nursing home, the three-acre facility now features a modern assisted living component that was added two years ago. This three-story complex is connected to the main facility. It enables residents who don't need a comprehensive nursing home atmosphere to live independently while giving them access to the services they might need from time to time. Still, at least 95 percent of the residents in the two buildings would require some level of assistance in evacuating the premises, should a fire alarm go off.

While some might need minimal help, others would require wheelchairs and other assistive devices. While nurses and other personnel in the facility are trained to handle this task, both residents and workers would like to avoid it unless absolutely necessary. In order to keep disruption to a minimum, the workers would need to be able to determine quickly whether there is actually a fire and, if there is, to determine its exact location so only the people in proximity to the fire have to be evacuated.

Until recently, neither of these capabilities was possible with the existing fire protection system. A conventional, 10-zone panel with about 300 points of protection incorporating pull stations, smoke detectors, and duct detectors had originally been installed in the facility. If a fire alarm were activated, the panel might show something such as, "Zone 1 North Wing." The problem was, a zone might contain 20 to 30 protection points, and facility personnel had to try to isolate exactly where the problem occurred. Determining whether there was a true fire emergency was very time-consuming. Consequently, in the interest of safety, everyone had to be evacuated--to the dismay of both workers and residents.

In addition, because the emergency could not be readily identified, the fire department had to err on the side of caution and dispatch engines to the scene. Given the size of the facility as well as the physical limitations of the residents, the fire department would normally send two or three fire trucks along with support equipment. Financially, the facility is responsible for costs incurred when fire trucks are dispatched. The ongoing costs of unnecessarily dispatching the fire department are significant, so minimizing false alarms was of paramount importance.

A Smarter System
The solution to this dilemma was an addressable system that would pinpoint the exact location of a potential fire "situation" and allow personnel to determine its true nature.

An addressable fire alarm system is one that provides the user with the status of the initiating devices that comprise the system network, be they smoke detectors, water flow switches, manual fire alarm boxes, or other emergency equipment. This status is easily viewed on the fire alarm system control unit and features not only information about the emergency device, but also detailed information about the device's "address." Joe Mesich, owner of Advanced Technical Services, also in Gallup, provided the fire protection system. At its heart is an intelligent analog/addressable fire control panel.

An analog/addressable system takes addressable systems one step further. It has the characteristics and features of an addressable system but expands on the information provided to the control panel. Detectors in analog/addressable systems become "sensors" that relay information to the control panel regarding how much smoke or heat the detector is sensing. The basic system installed here has a single Signaling Line Circuit (SLC) loop that can support 127 SLC devices, expandable to 1016 points (eight total SLC loops with a maximum of 127 devices per loop) using simple expansion cards. It features six on-board circuits that can be configured for notification outputs or for conventional smoke detector inputs. Ultimately, this is a flexible system that can be customized to suit Little Sisters' needs as they expand and change.

Mesich said its ability to pinpoint exact locations within the system is by far the primary benefit. "Between the nursing home side and the assisted living side, we've installed about 300 points of protection," he said. "The second a fire alarm goes off, personnel are instructed to go to whichever annunciator is closest to them. At every annunciator [one on each floor and one in the maintenance department] we have a list of all the points of protection, so personnel can scroll down and determine the exact location of the alarm.

"It is also important to note that analog/addressable devices are far less prone to false alarms," Mesich said. "Unlike conventional alarms, which can get false readings from the accumulation of dust and other contaminants, analog detectors are able to self-compensate for these smoke-reading inhibitors. With this 'drift compensation,' analog detectors are able to distinguish between a long-term drift in smoke detection due to contaminants and a short-term change in smoke detection resulting from a real fire.

"Concurrently, when a fire alarm goes off, our communications center will call the facility. They're instructed to verify whether there is actually a fire or if someone simply tripped a pull station or burned something in the kitchen. We don't actually dispatch the fire department unless they know it's a fire, which saves time, money, and resources. And if there is no fire, residents do not have to be evacuated. Both the residents and staff appreciate that aspect."

The Job's Done in Six Months
Mesich said the effectiveness of addressable systems virtually eliminates the need for conventional systems. "We don't actually do conventional systems any longer," he said. "If someone comes to us with a conventional system, we will insist on converting it to an addressable system. The only time we have installed a conventional system in the last five or six years is if we have to do a fire riser and maybe just one or two points."

Another advantage of the system is the calibration capability of the smoke detectors. If a smoke detector starts to get dirty, a signal is sent to the control panel with specific information about the location and nature of the trouble. Facility personnel will call and inform Mesich there is a problem. His people will then know exactly where to go to clean or replace the detector.

Having the system installed in both buildings was somewhat opportune. The general contractor that was working on the assisted living addition had decided to put in a new addressable fire protection, but only for the new site. However, when the construction crew was installing plumbing in the ground for the addition, they cut through the fire alarm conduits that connected the two buildings because of an error by the previous system installer. When Mesich's people attempted to put the system back together, it became apparent the job would be more difficult than anticipated. Mesich convinced Little Sisters' management that it would be better to simply convert the entire system over to an analog/addressable system.

"We started on the nursing home side making the conversion," said Mesich. "That process took about three months. By that time the assisted living site was about ready to go, so we began working on that. We then tied the whole facility together in one panel. The whole process took about six months."

Little Sisters now has a fire protection system that keeps its residents and workers safe while minimizing the disruptions to their daily lives that are caused by false alarms and unnecessary evacuations.

This article appeared in the February 2006 issue of Occupational Health & Safety.

This article originally appeared in the February 2006 issue of Occupational Health & Safety.