Susan Brady, Editor in Chief:
What criteria should a dealer use when deciding between specifying a conventional fire alarm system or an addressable fire alarm system?
Richard Roberts, System Sensor, Product Marketing Manager: It all depends on the level of system functionality and total installation cost. If the system is a basic straight forward type that activates a general alarm from one input, a conventional fire system is most likely sufficient. However, if one input activates several different outputs, then an addressable fire system would be most cost effective.
A typical type of application is a system that interfaces with an elevator system for capture/recall. The total system installation cost is a consideration as well. The cost of addressable initiating devices is typically 70% more than a conventional device. However, the installation labor and wiring costs of an addressable system is less than a conventional system because there are fewer conductors. The rule of thumb for many designers determining whether to install a hardwired or addressable system is: if the system has more than 10 IDC’s, an addressable is more cost effective.
Jeff Hendrickson, Silent Knight, Director of Marketing: Consider lifetime cost of the system. Addressable systems are easier to service and troubleshoot. They allow service personnel to identify malfunctioning sensors with pinpoint accuracy which helps reduce false alarm occurrences. Addressable systems are often easier to install because the wiring capability of the addressable system allows t-taps without supervision issues.
Tim Frankenberg, Potter Electric Signal Company, Fire and Security Product Manager: There are three things that come to mind. These include the size of the building being protected, demands of the AHJ and long term inspection, testing and maintenance. There comes a point to where installing a conventional system is no longer cost efficient. The technology is reaching the point where addressable makes sense in a building that in the past would require over 8 to 12 zones. Although the addressable peripherals are a higher front end cost, the features you gain on the addressable systems are much greater and, in the long term, the maintenance costs are reduced. It makes sense that on smaller buildings and some residential occupancies the conventional system is a better fit due to cost and the fewer features needed.
Many AHJs are now pushing for all addressable. The systems are generally there for two purposes: evacuate the building and notify the emergency services. Most of the emergency services (i.e. Fire Department) would prefer to know exactly where the area of the alarm is located to easily determine if a fire exists or not.
The inspection, testing, and maintenance of fire alarm systems are essential in keeping the system in a state of readiness. In smaller buildings, the conventional systems have fewer devices and have less interruption for testing. In larger buildings, the addressable systems allow testing of some to all of the devices, as well as the ability to bypass or disable certain features such as fire doors, HVAC equipment, or notification circuits.
Jack McNamara, BOSCH Product Manager for Fire Products: This is a difficult question. It mainly depends on application and time to find the alarm point. Where as a conventional zone can cover 20,000 square feet, or up to 22 smoke detectors, in an addressable system each of those detectors is called out as an individual point.
Brady: Older facilities, like a school for instance, often need upgrades to their fire systems. What is the best way for dealers to approach applications like this where they are in need of updating?
Roberts: I’ll address schools specifically. Many schools built in the 1980s only installed pull stations and a few notification appliances. Some school districts will only replace the pull stations, add a few smoke detectors and add ADA/UL 1971 notifications appliances. Some school districts will add smoke detectors throughout the school and voice evacuation to the gym, cafeteria and auditorium. The dealer should work with, or be aware of, local school district requirements and funding.