Raising the alarm
Fire alarms are vital to any building's life safety system, but which type is best for your project? MEP Middle East investigates the latest market offerings.
The first signal that most people will have of a fire in a building is when the alarm system sounds. Whether it is by siren, voice or flashing beacon, this alert is essential to a building's overall life safety system. How alarms are installed and operated must also be carefully considered to enable any fire to be quickly contained and eliminated, while ensuring the safe evacuation of the building occupants. And with the preference for high-rise buildings in the Middle East, ensuring that an effective system is installed has become even more important.
But with many different fire alarms available on the market, how do you decide which should be installed on a particular project?
Fire alarm systems fall broadly into two categories: conventional and analogue addressable. One of the main differences between these types is in the ease of locating any fire. Tyco Middle East business development manager Craig Nixon explains: "It's really to do with the identification of alarms: with conventional systems you may have a zone that could consist of up to 20 detectors, but [the fire alarm panel] wouldn't tell you which particular detector was in alarm mode, it indicates the zone only; with an addressable system [the system] pinpoints exactly which detector is in alarm.
This difference is due to the intelligence of the two systems and their installation.
With a typical conventional system the detector will send a signal to the fire alarm panel when a preset condition is reached; the panel in turn triggers the alarm sounders. Detectors are normally connected to the fire control panel via dedicated circuits, with each representing an area or zone in a building. Each zone may include a number of detectors, however the alarm panel will give the same signal regardless of which unit operates an alarm.
With an analogue addressable system the detectors are connected on a single loop that may cover several areas. However each detector has a unique address, so when it is triggered the fire alarm panel can identify the specific point in the building where the fire is occurring.
"The benefits of the analogue addressable system is that you can pinpoint the location of where the fire has been detected or the likelihood of a fire," confirms Bhasker Iyer, regional sales leader, Honeywell Building Solutions Middle East. "In a non-addressable installation, detectors are in one of two states - normal or alarm - individual detectors are not identified or given a specific address or location in the building," adds Hochiki Europe export sales manager Pervez Khan.
A third product type is that of digital addressable reports Tyco's Jonathan Gilbert. "The advantage of that type of system is that it's more robust," Gilbert states. "If you have electrical interference the current can change and you may get wrong readings [with analogue addressable systems]. Whereas a digital system like Tyco's MX Digital uses frequency shift key signalling which is unlikely to get interfered with by electricity," he adds.
The benefits of addressable systems also include that of future flexibility and the potential to adapt to changes in building use. "[With conventional systems] you don't have the flexibility to set the detector sensitivity, to adjust the day and night mode of operation or configure the system to suit whatever changes might come in the future," stresses Yusuf Audeh, commercial manager with Juma Al Majid, distributor of GE fire safety products.
The conventional system is a ready-made solution and there's a lot of restrictions on implementing sequencing operation and updating the fire control panel, whereas with addressable systems there are no restrictions. You can programme it hundreds of time, implement different sequencing and achieve whatever you need, most of the time by software," adds Audeh.
A qualified contractor must carry out installation of both system types, with different training needed for each. "The level of technicians skillsets for the analogue addressable systems has to be far greater," stresses Iyer.
A conventional system is fairly straightforward and easy to install, commission and maintain. In the case of analogue addressable systems there is a lot of commissioning involved in terms of trying to address the devices separately and then programming them to respond in different situations. It's far more intense in terms of the work involved," he adds. In an attempt to reduce the onsite installation time needed however, many of the latest products to be launched into the market can self-programme.
In general, conventional systems are suitable for use in smaller buildings or those with large open zones such as warehouses, where locating the source of a fire would be easier. Analogue addressable systems, being more suited to high-rise applications or buildings with several smaller areas, are becoming more popular and are now essential in certain areas.
Addressable systems generally must be installed in any building that is more than a few stories high and most consultants are specifying such systems as standard for high-rise projects and other large public buildings such as malls.
In September 2007 Dubai Civil Defence (DCD) took this change of technology one step further by issuing a memorandum stating that conventional fire alarm systems can no longer be used in the Emirate's buildings, with addressable systems to be installed as standard. "Dubai Civil Defence is pushing conventional technology out and driving the market to use only analogue systems," confirms Ashique Pannakkat, sales director Middle East, Cooper Middle East. This is aimed at increasing safety.
Traditionally the Middle East has been influenced by British and American standards and fire alarm products are deemed acceptable for use if they have been third-party tested to either standards. "Around 15-20 years ago the market was driven by British consultants, so British and European standards were prevalent, but now there is a general shift towards the American NFPA standards," states Pannakkat. This change is primarily being driven by the prevalence of American product manufacturers rather than any major benefits of one set of standards over another and their specifications are in fact very similar.
Increasing system reliability, flexibility and user-friendliness and reducing false alarms are main focuses of the latest product developments. "With analogue addressable systems we now have the technology to install the call sounders and detectors on the same loop, so you can send a detection message and a sounder message on the same wiring," explains Pannakkat. "The installation time is reduced and there are big savings because you don't have to run two cables," he adds. The detectors also are being updated, with increased intelligence in the latest products.
Honeywell's new Eclipse system uses a peer-to-peer fully digital protocol that gives a faster device response time and increased flexibility. Its digital technology means that it has higher noise immunity so is resilient and reliable. The peer-to-peer communications mean that building operators will be alerted of a problem within 0.25s.
For ease of maintenance, once the system has been installed the detectors can be checked using a handheld infrared remote controller. This means that no regular physical access is needed to units in hard to reach areas such as ceiling voids. Honeywell XLS3000 and Eclipse include Honeywell Smart technology, which automatically tracks NFPA required installation, inspection, testing and maintenance frequencies of the fire alarm system.
Cooper Lighting and Security's latest product offering is the base sounder beacon. This forms part of the firm's analogue addressable range, which is available in the Middle East through distributor Haven Fire and Security. The product combines a sounder, beacon and detector in one unit, making it particularly well suited to hotel applications.
Cooper also offers the CF3000 analogue fire system, which includes a wide range of analogue addressable detectors and ancillary devices. The sound type can be individually programmed to each alarm sounder from the touchscreen control panel so there is no need to access the unit once it is installed. All devices on the loop are auto-addressed using the firm's soft addressing protocol and include an integral short-circuit isolator.
Hochiki Europe has recently launched several new fire safety solutions that are available in the Gulf region, including the Firelink high-sensitivity smoke detection system and Firevac voice alarm system. Firevac includes several cost and installation time saving features, including the simple integration of the system with an existing fire alarm and detection installation.
There are two versions of Firelink available, the single-pipe Firelink-25, and the two- pipe Firelink-10. The main difference between the two is the recommended sampling pipe length and the number of sampling holes in each pipe. An explosion-proof version is also available that provides reliable high sensitivity smoke detection for high-hazard areas.
Further product launches into the market include those from Tyco Middle East, which offers a range of alarm solutions including the MX Triple sensing detector. This combines optical, thermal and carbon monoxide sensors into a single unit to enable early detection of fire and the reduction of false alarms.
Further product launches are due to take place at Intersec Middle East, further increasing the installer's choice and ultimately the safety of the region's buildings.