Fire Protection System - Assignment Example

Fire Protection System Name Date Course Fire Protection System Introduction Fire protection system is required in a building for the purposes of ensuring automatic response to fire is in place. The fire protection systems are useful in fighting the fire before the arrival of the fire fighters. Depending on the magnitude and size of the fire, some of the fire protection systems have the ability to put out fire in an apartment block on its own. The system also enables the occupants to leave the building before the magnitude of the fire increases (Batra, 2013). Properties can also be salvaged in the presence of a fire protection system. The features of the building as well as its characteristics play an important role in terms of determining the type of system that can be used. The main types of fire systems that are used in apartment buildings include residential water mist system and residential sprinkler system. A proper selection of the system is required during the process of designing the building (Batra, 2013). This is for the purposes of ensuring that it is effective in putting out the fire. A 25 meters building requires a system that will be effective in fighting the fire in the apartments. The building will have a single stair and it will be accessed through an extended common corridor. As a result of the features of the building, an effective system is required in order to ensure efficiency and safety of the system. The paper thus analyses the two types of system with regards to its features, pros and cons with a view of determining the most appropriate system. Discussion Residential water mist system Overview and how the system works A water mist system is a fire protection system that utilizes airborne water droplets to put out the fire in an apartment. The water mist is produced by forcing water through extremely fine orifices at a high pressure which range from 100 to 100 psi (Rosen, et al, 2014). The nozzles are usually connected to a water supply through a piping system. Heat sensitive glass bulb is used for actuating the water mist system. The heat activates the system in the event of fire. A cone spray is usually discharged through the system and it fills the protected zones in the event of a fire. The correct pressure must however be maintained at all times in order to ensure efficiency. This is an aspect that is usually considered during the design of the system. The positioning of the nozzles is important in ensuring that the water mist is able to cover the entire room. Some of the systems discharge gasses or additives that are useful in putting out the fire (Rosen, et al, 2014). The mist mainly put out the fire and prevents its spread through heat absorption and creation of a radiant heat barrier. The water most released also deprives the fire of oxygen through displacement. The characteristics make it effective in terms of fighting class B and Class K fires. Key design criteria that needs to be considered The process of designing the water mist system requires various considerations with regards to the building. The room size and shape is one of the factors that have to be considered. The system is effective in a maximum area of 400 square feet (Xie, et al, 2014). The ventilation system in the room is an important consideration that determines the installation of the water mist system. The system is susceptible to airflows which may render it ineffective. The ventilation in the open plan arrangement with mechanical extract system has a direct impact on the ventilation. Such an arrangement promotes airflow in and out of the building and it may affect the water mist system. However, pressure can be adjusted in order to ensure that it works effectively under the nature of the airflow in the building. Other factors that has to be considered is the location of objects and equipment within a building. In residential apartment, most of the objects and equipment are usually close to the floor in terms of height. The displacement of oxygen can therefore take place and ensure that the fire is prevented from spreading (Xie, et al, 2014). A single stair in a building limits the entry and exit of air into the building. The corridors and the number of doors are also factors that affects the efficiency of the system. Key components In a residential apartment, the mist water system is of low pressure with only a few components. This can be attributed to the lack of standards or pre-scribed form which is popular with the automatic water sprinkler. The components in a mist water system include the following: Fire fighting medium The fire fighting medium is a key component that is directly used for fighting the fire. In a water mist system, the fire fighting medium includes water with antifreeze, portable water, water with inert gas and water with additives (Rosen, et al, 2014). The fire fighting medium is usually released in the event of the fire and it forms the mist. Detection system This component is mainly used for detecting the fire and it relies on some or temperature. In a mist water system, the automatic quick response glass bulb is usually utilized. Smoke detectors and actuators are also used as part of the detection system. The cover plates may be used for covering the detection system components. An alarm, control panel and alarm system is also used as part of the detection system. The glass bulb is sensitive to temperature changes and it usually breaks automatically once the set temperature has been reached (Xie, et al, 2014). This allows for the system to release the mist. Atomization This component is mainly used for the transmission of water to the apartment under fire. It is comprised of a nozzle and orifice, filters and strainers, twin fluid system, single fluid system and the pressure system. The nozzle and orifice allows the mist to move out of the system to the apartment. The filters are used for the purposes of ensuring that only the mist is let out of the system (Zhong, Fan, Ji & Yang, 2013). The fluid system and the pressure systems are used for converting the water into mist before it is let out through the nozzle. Frequent maintenance and replacement of this component is required in order to ensure that it is fully functional at all time. Delivery The delivery system is a key component that ensures water is delivered to the system before it is converted into mist. A pipe is mainly used as a delivery system and it may be made of different materials. The pipes include the wet pipe system, dry pipe system, deluge system and pre-action system (Xie, et al, 2014). Stainless steel is an important material that is used in the delivery system. This is due to its physical characteristic that enables it to function effectively. Supply This component is where the water is stored ready for use in the fire fighting process. The supply system in most cases is a storage tank which may be located at the roof of the building. The town’s main can also be a source of supply (Zhong, Fan, Ji & Yang, 2013). Propellants such as nitrogen is used in some systems as a source of supply. The capacity of the supply is dependent on the size of the building. Pros and cons Pros The mist water system through heat absorption ensures that the fire is extinguished within a short period of time. This is important in ensuring that the lives of the occupants can be saved and destruction to property minimized. The damage by water to the equipment or furniture in the room after the fire is also reduced when the mist system is used (Rosen, et al, 2014). The use of water usually leads to damages due to the high pressure involved. The amount of water required to put out the fire is greatly reduced through the use of this system. The mist can last for a period of up to 30 minutes in an apartment and this only requires a minimal amount of water. The use of this system is environmentally friends as compared to other methods of firefighting. This can be attributed to the use of non-toxic agents during the process of putting out the fire. Cons The equipment is quite complex and expensive which may increase the costs during the construction of the building. The testing process is also expensive and it leads to an increased cost for the building. The water mist system is complex which impacts negatively on the maintenance process. The reliability of the system is low due to the complexities involved during the maintenance and testing process. During the testing process, it is difficult to predict al the situations with the use of the water mist system (Zhong, Fan, Ji & Yang, 2013). The failure of the system during a fire event may have a lot of negative impacts on the occupants of the building as well as the property in the residential building. The system is not effective in apartments that are highly ventilated which makes it restricted to certain types of buildings. Residential sprinkler system Overview and how the system works A residential sprinkler system is an active fire protection method that relies on water supply to put out the fire. The residential sprinkler system is usually held by a heat sensitive glass that is linked with a fusible alloy. The glass plays an important role in applying pressure to a piped cap that acts as a plug (Cao, et al, 2014). It prevents the flow of water when the design activation temperature has not been attained. In a residential apartment, several sprinklers may be installed in a room. However, the activation is based on the individual sprinklers. Only the sprinkler that is close to the fire is activated and it may be enough to put out the fire. The activation of the sprinkler in most cases is within 1 to four minutes after the start of the fire. The residential sprinkler system is usually located at the roof of the apartment in most of the buildings. About 20-40 gallons of water is usually discharged by a residential sprinkler in 1 minute. The pressure of the water is usually regulated during the design process. The pressure of the residential sprinkler system in most cases is 50 psi (Cao, et al, 2014). Directing the water at the fire ensures that it is extinguished immediately. The water discharged also wets the materials and hence stopping the spread of fire in the building. Key design criteria that needs to be considered The size of the building is one of the main aspects that has to be considered during the design process. This is for the purposes of determining the number of sprinklers that needs to be installed. An individual sprinkler can work for a space of up to 600 square feet. Ventilation is also an aspect that needs to be considered. The size of the windows and doors influences the entry of air in a compartment (Zhao, Zhao, Jiang, Luo & Zhang, 2015). The system may not be effective if it has a high number of open spaces such as windows and doors. A high number of open spaces allows for the entry of air in the building and this may affect the direction of water flow under windy conditions. The protected mechanical extract that will be installed in the building is likely to affect the ventilation that this may ensure that the sprinkler is working effectively. The extended corridor may however affect the entry of air movement which may affect the efficiency of the water sprinkler. Key components In order for the sprinkler system to work effectively, all the components must be fully functional. Frequent maintenance of the components is required in order to ensure its functionality. Alarm valve The alarm valve is a one way valve that is opened only when the sprinkler head is open. It plays an important role in controlling the flow of water into the fire sprinkler system. This valve usually takes over from the stop valve when the system is activated in the event of a fire (Zhao, Zhao, Jiang, Luo & Zhang, 2015). This component requires frequent maintenance in order to ensure that it is effective. Alarm test valve The alarm test valve plays an essential role in ensuring that the system is tested on a weekly basis when it is shut-off. This valve is useful during the maintenance process as it allows for the pump to be run without flooding the apartment (Yamamoto, Takeuchi & Nishiki, 2015). Motorized alarm The motorized alarm is used for alerting the occupants of the building about the fire. It is usually turned on automatically when fire sprinkler is turned on. This is usually achieved through the action of a hammer striking a bell as a result of the flow of the water (Yamamoto, Takeuchi & Nishiki, 2015). The noise is usually loud enough to alert the occupants of the apartment about the danger. Sprinkler heads This is one of the main components of the residential sprinkler system that is usually visible at the location that it has been stored. The sprinkler head plays an essential role in terms of containing the flow of water (Soroushian, et al, 2014). It ensures that the water only flows at the area that the fire is occurring. It therefore ensures that the water does not flood the residential room. Stop valve The stop valve in a residential component is always red in colour and is always locked in the open position. It plays an important role in preventing the flow of water from other sources such as the municipal water supply when the system fails to go off (Soroushian, et al, 2014). Pressure switch The pressure switch is used for alerting the fire department that the sprinkler system is going off. This is mainly based on the water pressure (Yamamoto, Takeuchi & Nishiki, 2015). It can therefore enable the fire department to use the necessary measures to respond to the fire. Water supply The supply of water in a residential sprinkler system is mainly through the water supply tank that is located within the building (Soroushian, et al, 2014). However, the water may also be supplied from the municipal mains. Pros and cons Pros The residential fire sprinkler uses less water as compared to the municipal fire hoses stream which discharges about 900 liters of water per minute (Soroushian, et al, 2014). The high amount of water discharged may also lead to damages to the apartment a well as the contents in the apartment. Flooding the rooms is also common when the municipal hose stream is used. The sprinkler ensures that the water is only directed at the fire and hence reducing the incidences of flooding the room. The sprinkler system can be used under different conditions including an open plan arrangement. Residential sprinkler system is much easier to maintain which ensures effectiveness in times of fire. The fire can be put out within a short period of time due to the water pressure and amount directed towards the fire. The system is easy to install and does not requires much costs. Its levels of accuracy in combating the fire are also high as compared to the other systems. Cons The use of the system may not be effective under windy conditions and large number of open spaces to the exterior of the building. The system may also be ineffective in the presence of unreliable water supply. The differences in pressure at the pipes may impact negatively on the movement of water and hence reducing the efficiency of the system during the process of putting out fire. Delays may be experience during the process of delivering the water of the sprinkler as the pipes in some cases are dry (Yamamoto, Takeuchi & Nishiki, 2015). This may impact negatively on the ability to save lives and prevent damage to properties. Conclusion In conclusion, it is evident that the presence of a fire system is important in ensuring that the building is secured from an event of fire. The two fire systems that may be used for the building is the residential mist water system and the residential sprinkler system. The residential mist system utilizes water converted to mist while the residential sprinkler system utilizes water to put out the fire. It is evident that the mechanism of putting out the fire is the same but the components are different. It is evident that airflow in the building may impact negatively on the efficiency of the residential mist system. The sprinkler system may also be affected by wind incase the apartment has huge windows or large open spaces. The sprinkler may however be effective in the building due to its components as well as advantages. The ventilation in the apartment may affect the residential mist system. References Rosen, J.S. et al., 2014. 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