The status quo in fire protection

June 2003 Fire & Safety

Fire can be devastating in regard to both private and commercial properties and all too often by the time the fire service is able to react major damage has already occurred.

Immediate damage is of course only one problem as valuable inventory and information may have been lost and a return to normality can take considerable time, effort and expense. Sprinkler systems are already in fairly widespread use but they react only when the temperature indicates that the situation is severe, and false triggering can in many cases cause almost as much damage as a fire. The efficacy of such systems also depends on the availability of an adequate water supply and recent examples where sprinklers were ineffective include the fire at the Makro store in Woodmead.

Water is also not a friendly extinguishing medium, particularly where electronics and computers are concerned and other options should be considered. The earliest way in which to detect fire is of course through the use of smoke detectors while various gases such as CO2, FM200 (a halon substitute) and argon can be used for fire suppression without damaging electronic equipment, archives and magnetic media.

A recent and interesting case study is the protection of the Discovery Health Head Office building in Sandton, the contract being awarded to Security & Fire Projects (SFP) as a result of the state-of-the-art solution offered, the company's reputation and a keen price. The requirement was for a smoke detection, fire suppression and evacuation system with a sound masking/white noise system also being required for the open plan offices. The system went live in April 2001 and a full two year warranty was offered by SFP who are now in the process of negotiating a continued service and maintenance contract. It is of importance to note that aftersales support (to deal with even minor system problems) is as critical as the installation itself and here SFP offer a full 24/7 service, with someone always available to answer a call out.

Advanced technology solution

Cape-based Ziton was chosen to supply both their ZP3 analog addressable control panel and most of the smoke detectors. The ZP3 is both an advanced technology solution meeting local and international standards while it provides maximum flexibility combining comprehensive hardware together with highly configurable software. In the initial configuration three control panels (each supporting up to 127 line devices) were installed and networked but the addition of new closed-off offices required the addition of a fourth control panel. All of the control panels and line devices are networked via RS232 to a single fire graphics computer located in the control room itself. The ZP3 is configured to provide constant communication with the sensors and can be programmed to provide sensitivity adjustment. Variations in the sensor's environment caused by increases in temperature are reported to the panel where they are processed and compared to known fire data prior to any alarm output being activated. The system is also networked to the fire telephones that are installed on every floor in the fire escape route.

Full functionality

The fire graphics computer offers full functionality from the control room and alarms can be acknowledged and the fire control panels reset remotely where required. The graphics software displays the area in which the alarm has originated. In the two years of operation of the fire control system at the Discovery Health HQ there have only been two 'false positive' alarms. These both occurred in kitchen areas where relocated hot objects (such as an urn) have triggered the heat detectors used in these special zones.

All areas of the building (including bathrooms) are monitored mostly through the use of optical smoke detectors, with kitchens and rest areas making more sensible use of heat detectors. The building and floors are divided into zones and a 'double knock' (two smoke detectors triggered) in a single zone results in the automatic shutdown of the airconditioning system and the start up of a smoke extraction system. This alarm state also causes the elevators to return to the ground floor and then stop operating. The alarm is also interfaced with the building access control system that receives a fire override command that unlocks the turnstiles at the main entrance. In addition to the normal sirens triggered by the fire alarm the PA system is activated in the affected zone (or the entire building) to provide pre-recorded evacuation instructions or additional audible alarms. All of these safety and evacuation procedures remain in operation until either the fire panels have been reset or this is done remotely through the fire control computer.

The Ziton fire panel network is connected to a Remrad radio transmission system that provides a direct link to the Sandton Fire Department, which is immediately notified of the alarm state. This two-way link also provides voice communication so that the extent of the threat, or a false alarm situation, can be confirmed before fire tenders are despatched.

Although the building has a water sprinkler system fitted, this is a last resort to a major fire and the SFP system is not used to trigger this (the system will in fact operate independently under high temperature conditions). What it does do however is monitor water usage so faulty or incorrectly triggered sprinkler heads can be identified and attended to.

High risk areas

The Discovery Health building has a number of unmanned, but particularly sensitive areas, 17 in total, that require additional special fire protection to minimise damage and downtime in the event of fire. These areas include the computer server room, electrical rooms, networking clusters and the emergency power centre that houses the UPS systems and switching gear. All of these areas are considered as high risk in terms of fire generation and are also critical to continuing operations. Here FM200 gas fire suppression systems have been installed while detection is beefed up through using both optical and ionisation sensors (wired to two independent detector zones). These sensors are connected to a standalone Kentech Gas Extinguishing Panel; one dedicated to each of the specially protected areas.

Here again the 'two knock' fire condition is applied and this immediately results in the release of the FM200 gas into the area independent of the Ziton building detection system although the alarm and gas activation signals are transmitted to the fire control computer with the location of the threat. A total of 1000 kg of FM200 is available in the building and this ozone friendly gas can be discharged in a matter of seconds extinguishing a fire in a confined space and minimising damage to critical systems, computers and electronics.

Although the Discovery Health building has been used as a case study, SFP have installed similar and more comprehensive systems at many other key sites in South Africa and beyond our borders. These include the new Head Office of MTN in Johannesburg (completed in April 2003) where an integrated fire and access control solution was provided. Additional security features provided by SFP for this site include an electric fence and motion detection system. Another recent installation was the fire and access control system at the Nedcor Headquarters in Sandton, which is a seven-building complex. Besides office blocks SFP has been responsible for the installation of similar fire control systems in the stores and warehouses of several supermarkets. One of the more unusual installations was the fire alarm system on the SAS Outeniqua. All of the systems supplied by SFP comply with the strict SABS and other international fire code standards.

SFP, which is in the process of obtaining certification to ISO 9000:2000, offers solutions that cover the entire fire and security spectrum. The product range offered includes fire detection, gas protection, PA and evacuation systems, access control, intrusion detection, asset tracking and CCTV. Through its branches in Johannesburg, Cape Town and Durban the company offers a countrywide service. SFP designs, manages the installation, commissions and maintains installed systems using products manufactured by leading local and international suppliers. Experienced sub-contractors who have proven their capability to SFP carry out installations. The company holds a range of spares appropriate to its installed base and potential component/system obsolescence.





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