Fire Alarm Systems: Interesting Facts to Know Before Buying
Installing fire alarms may seem like a pretty straightforward process, but in reality, it’s the complete opposite. With so many different types of alarms available nowadays and strict building codes, especially for commercial buildings, setting up a fire alarm system requires a lot of considerations upfront. That being said, if you’re looking to install an alarm system in your commercial facility, you’ll need to know what exactly you need and how you need to do it. The purpose of this article is precisely that – to help you make all the right decisions by providing you with the basic information about alarm systems.
First and foremost, you need to know that there are several different types of fire alarm systems. One of them is non-addressable, also known as a conventional system. In these systems, the input devices operate like a switch. When they’re active, they turn on the panel, which turns on the sounders or bells. The input devices in a specific zone are connected to a single circuit also known as a ‘zone’ so that an indicator on the main control panel will light to show which area is activated. The sounds in theses systems are wired on separated sounder circuits. Conventional systems are ideal for smaller business premises like shops and offices.
Another type of fire alarm systems are analog addressable systems. These are wired on ring circuits also known as ‘loops’. The output devices in these systems electronically “talk’ to the control panels, and the input devices constantly send back their analog value. The analog value corresponds to the temperature of the air and the smoke present around the detectors. These alarms are “intelligent” and decide for themselves when a device has reached the alarm value. The controls can instruct one or more output devices to operate, and they can be set to operate specific outputs according to which the input device is being operated. These systems are ideal for larger premises, like shopping centers, hospitals, office complexes, factories, and warehouses.
Then, there are radio fire alarm systems that are just like analogue systems but without all the wiring. Instead, these systems use batteries. Further, some analogue systems can have radio extensions for the hard-to-reach places, and they can be installed as hardwired, radio, or a combination of both. All analogue systems are software-based and require a fair bit of programming. That being said, in order for these systems to operate and to be maintained, you’ll need to give the installing and maintenance company access to the software. Having access to the right software and having proper training is key to installing and maintaining an alarm system properly.
No matter what type of alarm system you end up going for, you’re going to need detectors, including smoke detectors like optical, beam and iodization detectors, as well as an aspiring smoke detection system. Optical smoke detectors use infrared light to refract off of smoke particles that enter its chamber. This makes them sensitive to smoldering fires like modern furnishings and fabrics. However, they’re more prone to false alarms if your environment is dusty or steamy. Beam detectors, on the other hand, feature a transmitter and receiver which emit an infrared beam and detect smoke. Ionisation detectors work on the principle of charred smoke particles passing through two electrodes causing current flow. This makes them suitable for fast flaming fires from paper or wood. Iodisation detectors are prone to false alarms from burning smells like outside of a kitchen. And lastly, aspirating smoke detection systems which draw a sample from the atmosphere and pump it into a detector which can be located remotely from the protected area.
When the fire alarm system is triggered, an audible warning will be given in order to alert the people on the premises that they must evacuate. The most common type of audible alarm devices are electronic sounders, although there are some buildings that use bells. However, nowadays, it’s becoming common to supplement audible devices with visual alarm devices, also known as VADs. VADs are basically strobe lights that can be used to alert people that have hearing difficulties, and they’re commonly used in areas with high levels of background noises. In addition to sounders, many larger properties may opt to use voice evacuation known as Public Address Voice Alarms or PAVA. Although the premises doesn’t necessarily need to be large in order to have some form of PAVA, the fact that even the most basic forms are costly makes smaller businesses avoid them.
And lastly, it’s important for all the cables and wiring of the detectors and sounders to be completely fire resistant. Fire-resistant cabling and wiring are split into two categories – standard and enhanced. Make sure to check in with the cable manufacturers for compliance with the Australian Standards details where the different grades of protection must be used.
