Reputation is a fragile thing. Years of hard work building a successful business and providing good and efficient service to thousands of happy and thankful customers can be completely undermined in an instant by a single incident. To re-establish the same level of reputation may well take many more years.
One example of such a damaging incident would be the outbreak of fire in a hotel. Even when nobody is hurt, a single incident where prevention measures fail and fire is known to have started can result in the complete erosion of trust so vital to guests staying under the hotel’s care. Yet paradoxically, any occurrence of unwanted or ‘false’ alarms will irritate and alienate even the most reasonable guests when the alarms are eventually proven to be groundless, especially when they happen at night.
With so many different sorts of area which all need different levels of fire protection – guest rooms, kitchens, laundry and drying rooms, and plant rooms as examples – the problems involved in providing completely reliable fire protection within hotels are multi-faceted and complex.
Guestrooms
Typically, guestrooms occupy a large proportion of any hotel. It is not surprising therefore that guest rooms, which house a wide variety of possible ignition sources such as overheating electrical devices, cooking facilities and even misbehaving occupants, are the primary origin of non-confined fires in hotels. According to the US’s National Fire Protection Association (NFPA), they are also responsible for around 72 percent of civilian deaths. Most fires in hotel rooms start with an incipient, smoldering stage and, if detected early enough, can often be extinguished simply by removing the source of power (in the case of an electrical fire), or with water or an extinguisher of the appropriate variety.
It is critical therefore for the safety of all occupants of the hotel that all potential sources of ignition or combustion are kept to an absolute minimum within the rooms. Guests should be made aware of the hotel’s stance on smoking, handling open flames such as candles or behaving in any way which might lead to the outbreak of fire. All electrical equipment such as television sets, fridges, kettles and irons, must be well maintained, carefully cleaned and checked on a regular basis. Every guestroom should be fitted with at least one automatic, point-type smoke detector and this should be installed in such a way that it delivers the earliest possible warning of fire. On no account should it be susceptible to false alarms caused by deceptive phenomena such as steam from the shower.
The type, setting and positioning of the detectors should be determined by the likelihood of this deceptive phenomena which generally has less impact on bigger, higher rooms. In small guest rooms, intelligent multi-criteria fire detectors must be used to guarantee early fire detection and high immunity to such deceptions. To ensure reliable operation, the detector in a guest room must be sited in an area where fire phenomena such as smoke may easily reach the detector and where the intensity of possible deceptive phenomena are as low as possible. Special attention must be given to the hotel’s HVAC (heating, ventilation and air conditioning) system, so that in the event of a fire, the system does not prevent smoke from reaching the devices in sufficient concentration.
Kitchens
In commercial kitchens – and those in hotels are no exception – the open flames, grease traps, large cooking pots, kettles, frying pans and deep fat fryers present a very real hazard because of high fire load and the potential for catching fire if overheated. This makes the kitchen one of the most dangerous places in the hotel. But there is little possibility of eliminating or even reducing all sources of ignition here.
However several sensible yet simple precautions can be put in place to limit the risk of fire. These include keeping flammable materials such as cardboard or paper packaging to a minimum and always away from the flames of cookers. Taking care when lighting all devices, especially gas stoves, should be an obvious procedure, along with turning off electrical appliances when they are no longer required. Oven mitts, tea towels and other combustible cloths should not be left around the stove and, if not wanted for a long period, turning off the gas supply is another sensible precaution. Again, regular cleaning, checking and maintenance of all appliances is not only a wise move as regards hygiene of the equipment but also from the point of its safe operation.
Traditionally smoke detectors have not been used in commercial kitchens. Again the problem of steam and other deceptive phenomena makes their installation impractical, only much more so. When planning and implementing any fire detection solution for a hotel kitchen, the increased fire risk, the steam and the sudden, rapid rises in temperature caused by activity in the kitchen must be taken into consideration. Where detectors have been used in kitchens in the past, they were usually heat detectors which triggered an alarm at a pre-determined maximum temperature around 80°C. More often, fire blankets were positioned around the kitchen so that occupants of the kitchen could use them to suppress any outbreak. Manual call points were installed so the alarm could be raised if the incident escalated. However, some of today’s devices are able to differentiate between the aerosols caused by cooking and the characteristics of combustion. They are able to assess signals intelligently, can be adapted to ambient conditions and can be set up to respond appropriately to the many occurrences of steam that is a constant feature of busy kitchens. When positioned outside the immediate cooking area, where the rapid temperature increase caused by cooking, frying and opening ovens is less immediate, such detectors can effectively cover even the largest commercial kitchens and will even detect smoldering fire as well as the outbreak of open flame. Just as in the hotel’s guestrooms, these detectors should be mounted away from the direct flow of the ventilation or air-conditioning systems so that any airborne particles of genuine smoke are not diluted before they reach the detectors.
Laundries
Laundries too are relatively critical areas in hotels. With lots of combustible materials such as cleaning agents and fabrics, there is usually a high fire load and the possible overheating of various heavily worked electrical equipment – most involving integral heating elements – also presents a high fire risk. Again deceptive phenomena such as steam and dust is more than likely to be present. Fire detectors which guarantee an early warning whilst guarding against unwanted alarms are needed to alert and evacuate all parties at risk and to activate the relevant fire control installations.
The main causes of fires in laundries are technical defects. Just as in the kitchen, certain procedures such as regular cleaning, checking and maintenance of all appliances can help minimize the number of potential ignition sources. Again removing all unnecessary flammable materials such as paper or cardboard packaging is also vital. The heat within the laundry area can cause a reaction between oxygen within the atmosphere and unsaturated fatty acids, so grease-affected textiles should be cleaned separately and warm fabrics and items of clothing should not be stacked or packed whilst still warm.
As in the kitchen, the best possible fire protection will be achieved if the detection system is designed in such a way that the detection behavior automatically adapts to the environmental conditions. Intelligent fire detectors enable time dependent or event controlled detection behaviors. This feature allows, during the time the laundry is in operation, to set the system to alarm when there is medium smoke generation. But when it is not, the system should be set to alert as soon as there is only little smoke generation. In addition to the automatic fire detectors, manual call points should, of course, be installed for manual triggering.
Plant rooms
The plant rooms of hotels are usually quite limited in space but can house critical power supply, control, security or IT and communications systems. As unrestricted availability of each of these systems is a fundamental requisite for the hotel’s continued operation, these rooms especially need protection from fire. Due to the enormous business impact if one of these systems go out of operation, the plant rooms pose a high fire risk. When electrical and electronic components overheat, small quantities of aerosol are generated. If the overheating is not detected, a smoldering fire will develop during which smoke becomes increasingly visible. If the problem is noticed at this point, the fire can be extinguished easily with damage limited to a single device or area.
During the smoldering stage, little heat is generated which means that the increased aerosol concentration is not lifted and carried through a wide area. Also if the systems are being constantly ventilated to keep temperatures of the hardware and cabling down, the high airflow will dilute the concentration of aerosols. Fortunately this means that the lowest aerosol concentrations which must be detected to keep the area safe, can be measured and monitored by aspirating smoke detection (ASD) set to the highest levels of sensitivity.
These systems are able to generate different warnings and alarms but are also used to activate the appropriate extinguishing systems. Extinguishing systems using inert gases or dry chemical agents are ideally suited to protecting delicate electronic equipment. However, recent findings have shown that malfunctions can occur in hard disk drives (HDD) caused by the high noise levels that happen when automated extinguishing systems are released.
These malfunctions range from automatic shutdowns to more severe disturbances resulting in a loss of data. So, if possible, it is advisable to improve the room’s acoustics, to extend the discharge time and to use only those nozzles that keep noise levels below those that pose a risk during discharge. To protect structural damage to the area, all gaseous systems also need pressure-relief openings
Complete fire protection for hotels
The problems involved in providing comprehensive fire protection for hotels are complex. In short, to protect the guests and staff of any hotel throughout the day and night, along with the building itself, its reputation and its business continuity, it is necessary to put certain procedures in place: the regular cleaning, checking and maintenance of all appliances; the removal of flammable materials and the elimination of obstacles from stairways and all evacuation routes; the positioning of informative signs and notices keeping guests informed of restricted practices, alarms, practice drills and evacuation procedures; the siting of all types of relevant fire extinguishers; the keeping of all possible sources of ignition to an absolute minimum; the siting of manual call points throughout the hotel in all the appropriate places – along with the full and adequate training of all staff, both full-time and part-time.
It is vitally important for hotel owners and operators to utilize the protection of an early warning fire system which features intelligent detectors able to differentiate between the outbreak of fire and other, naturally occurring, deceptive phenomena. False fire alarms are a major issue for the hotel industry and must be avoided. The logistical problems of evacuating the hotel when dealing with large numbers of guests can be significant. The problems when dealing with those same inconvenienced customers when an unnecessary evacuation happens at night-time can be much greater.
Detectors should be positioned where they are not adversely affected by the hotel’s ventilation system or other influences that detract from their performance. In doing so, it is possible to provide effective and reliable detection at the earliest possible opportunity of the outbreak of fire starting in all possible ways – without causing the unwanted day or night-time alarms that alienate the hotel’s guests. This intelligent
system should be allied with, if possible, a reliable and effective extinguishing system in those parts of the hotel wherever it is practical.
For further information, go to www.siemens.com/infrastructure-cities
About the Author
Markus Späni is Application Manager in fire protection at Siemens Building Technologies.
