Engineering Design Practices 2008-2009 - Article Example

Engineering Design Practices 2008-2009 Fire Safety & Case Study Submitted By: Date: Introduction Fire results in destruction of the home and of treasured personal belongings. According to Communities and Local Government (CGI) statistics shows that UK suffers around 500 fatalities and around 13,000 injuries in over 52,000 dwelling fires in year 2008. Though there is a grate decrease in dwelling fires from past years but still fire destruction need to control. Essential Fire Safety Measures are safety installations in a building that helps in reducing risk to life and property in the event of fire. Fire safety measures include those safety measures that are planned during the construction of a building or implemented in structures that are already standing. Means of warning and escape The building should be designed and constructed in such a manner that there are appropriate provisions for the early warning of fire, and appropriate means of escape in case of fire. Fire measures should be designed in such a way which limits the rapid spread of smoke and fumes. The basic principles for the design of means of escape are: From most situations, there should be alternative means of escape; Where direct escape to a place of safety is not possible, then it should be possible to reach a place of relevant safety, such as a protected stairway, which is on a route to an exit, within a reasonable travel distance; Unprotected escape routes should be limited in extent of that people do not have to travel excessive distances while exposed to the immediate danger of fire and smoke. Protected stairways should design in such a manner that flames, smoke and gases must be excluded from escape routes by fire resisting construction and doors or by an appropriate smoke control system, or by a combination of both of these methods. Fire Alarm System The installation of smoke alarms, automatic fire detection and alarm systems in dwelling houses can increase the level of safety by automatically giving an early warning of fire. According to Building Regulation 2000 Document B A large dwelling house having more than one storey which exceeded 200m2 should be fitted with a fire detection and fire alarm system. Where new habitable rooms are provided above the ground floor level, or where they are provided at ground floor level and there is no final exit from the new room, a fire detection and fire alarm system should be installed. Smoke alarms should be provided in the circulation spaces within 7.5m of the door between sleeping spaces and places where fires are most likely to start(e.g. kitchens and living rooms) to pick up smoke in early stages of a fire. There should be at least one smoke alarm on every story of a dwelling house. If more than one alarm is installed then they should be linked so that detection of smoke or heat by one unit operates the alarm signal in all of them. Smoke alarms/detectors should be sited so that they are ceiling-mounted and at least 300mm from walls and light fittings. The sensor in ceiling-mounted devices should between 25mm and 600mm below the ceiling (25-150mm in the case of heat detectors or heat alarms). Smoke alarms should not be fixed over a stair or any other opening between floors. They should not be fixed next to or directly above heaters or air-conditioning outlets. They should also avoid bathrooms, showers, cooking areas or garages, or any other place where steam, condensation or fumes could give false alarms. It is essential that fire detection and fire alarm systems are properly designed, installed and maintained. Means of escape According to Building Regulation 2000 Document B following are different means of escape: Ground Story Except for kitchen, all habitable rooms in the ground story should open directly onto a hall leading to the entrance or other suitable exit. Should have a window which is at least 0.33m2 and at least 450mm high and 450mm wide and the bottom of the window should be not more than 1100mm above the floor. Upper Floor not more than 4.5m above ground level Except for kitchen, all habitable rooms in the upper story should have direct access to a protected stairway. Should have a window which is at least 0.33m2 and at least 450mm high and 450mm wide. Inner Room- The following arrangements are applicable for inner room: the inner room should not be likely to have more than 20 occupants; the inner room should not be a bedroom; the escape route from the inner room should not pass through more than one outer room; The travel distance from any point in the inner room to the exit(s) from the access room should not exceed the appropriate limit. one of the following arrangements are made: the enclosures (walls or partitions) of the inner room are stopped at least 500 mm below the ceiling, or a vision panel is located in the enclosure of the inner room, of sufficient size, to enable occupants of the inner room to see if a fire has started in the outer room, The access room is fitted with suitable fire detection and alarm system to warn the occupants of the inner room should an outbreak of fire occur in the access room. The stairway in the ground and first storey should be enclosed with walls and/or partitions which are fire-resisting, and the enclosure should either: extend to a final exit; or Give access to at least two escape routes at ground level, each delivering to final exits and separated from each other by fire-resisting construction and self-closing fire doors. Fire spread and Internal Linings Internal Lining means the materials and products used in lining any partition, wall, ceiling or other internal structure. According to Building Regulation 2000 Document B, to control the spread of fire within the building, the internal lining shall: Adequately resist the spread of flame over their surfaces; and Have a low rate of heat release or a low rate of fire growth. The choice of material for walls and ceiling can affect the spread of a fire. Cavity Barriers can be used in some concealed floor or roof spaces but this need can be reduced by the use of a fire-resisting ceiling below the cavity Internal Fire Spread (Structure) The building should be designed and constructed in such a manner that it maintains its stability for a reasonable period in the event of fire. A wall common to two or more buildings should be constructed to resist the spread of fire between two buildings. This can be achieved by maintaining load bearing capacity (which applies to load bearing elements only), sub-dividing the building with fire-resisting construction and installing suitable automatic fire suppression systems. According to Building Regulation 2000 Document B, every compartment wall and compartment floor should: Form a complete barrier to fire between the compartments they separated; and Compartment walls should run the full height of the building in a continuous vertical plane. Thus, adjoining buildings should only be separated by walls, not floors. Junction of compartment wall or compartment floor with other walls should maintain the fire resistance. External Fire Spread The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building. If the wall is 1000mm or more from the relevant boundary, a reduced standard of fire resistance is accepted in most cases and the wall only needs fire resistance from inside. The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building. Access and facilities for the fire and rescue services The building shall be designed and constructed in such a manner that it facilitates to firefighter in the protection of life. For this, there should be sufficient fire mains. Fire mains are pipes installed in and around a building and equipped so that the fire service may connect hoses to receive a supply of water. For effective firefighting operations, fire brigade appliances should be able to get within easy reach of a building. Fire brigade vehicle access to the exterior of a building is required to enable high reach appliances, such as turntable ladders and hydraulic platforms, to be deployed, and to enable pumping appliances to supply water and equipment for firefighting. Other fire Safety Measures Electrical Installations and Protected circuits: An electrical transformer or substation room and any associated main switch room should be located on the perimeter of the building with an external access door. The location on the perimeter including external access to the relevant room to be discussed with the electricity distribution system operator. Fire Extinguisher: It is an active fire protection device used to extinguish or control small fires. These should be mounted in the kitchen, garage and workshop. Check the extinguisher monthly for leaks. Case Study As per the provided layout of Mr. and Mrs. Jones, the following fire safety measures should be taken care: Ground Floor A fire detection and fire alarm system need to install in kitchen, dining and study/family room. Smoke alarm need to install in kitchen and dining room in the circulation space to pick up smoke in early stage of a fire and all need to be linked so that detection of smoke or heat by one unit operates the alarm signal in all of them. There should be a compatible interlinked heat detector or heat alarm in the kitchen, in addition to whatever smoke alarms are needed in the circulation space(s). Smoke alarms/detectors should be sited so that they are ceiling-mounted and at least 300mm from walls and light fittings (unless light fitting will not adversely affect the efficiency of the detector). The sensor in ceiling-mounted devices should between 25mm and 600mm below the ceiling (25-150mm in the case of heat detectors or heat alarms). Make sure smoke alarms should not be fixed next to or directly above heaters or air-conditioning outlets. They should also avoid bathrooms, showers, cooking areas or garages, or any other place where steam, condensation or fumes could give false alarms. All doors giving access to external escape stairs should be fire-resisting. Sufficient fire mains need to install in Lounge and entrance. The stairway need to be enclosed with walls and/partitions which are fire-resisting as it extends to final exit. It also requires escape lighting. Use that type of ceiling which can contribute to the overall fire resistance of a floor/ceiling assembly like Cavity or thermoplastic materials. Every cavity barrier should be constructed to provide at least 30 minutes fire resistance. Maintain load bearing capacity for first floor and subdivide first floor and ground floor with fire-resisting construction. Install a Fire Extinguisher device in kitchen. Pass all openings for pipes, ducts, conduits or cables through any part of a fire-separating element. First Floor A fire detection and fire alarm system need to install in Master bedroom, bedroom4, bedroom2, bedroom3 and bedroom5. All doors giving access to external escape stairs should be fire-resisting. The stairway need to be enclosed with walls and/partitions which are fire-resisting as it extends to final exit. Install a Fire Extinguisher device outside the master bedroom. References Building regulation 2000 Fire safety - Document B, Communities and Local Government, UK. Website: www.fire.kilkennycoco.ie/ Website: www.firesnoop.com Read More