A Number of Potential Fire Sources and Risk Points in the Details of the House Plan - Report Example

Abstract: 1.1 This report is about Mr and Mrs. Jones newly constructed home’s compliance with the fire safety regulations particularly the requirements set in Building Regulations 2000 or Approved Document B. In view of the need to determine compliance and apply the requirements of fire safety regulations in case of deficiencies, a critical evaluation of the house plan is necessary. Although the report found some minor problems with the house plan, it is generally in accordance with the standard specified by the current fire safety regulations. Introduction: 1.2 Fires can be very tormenting and it is considered a serious threat in most homes. It can destroy properties, harm individuals severely, and take people’s lives. However, fires are preventable and can be controlled and there are some ways in which people can reduce the risk, occurrences, and spread of fires in their homes. Fire safety plan include structural features and procedures needed to achieve the overall aim of fire safety to ensure that everyone reaches safety if there is a fire. Generally, it covers escape routes and fire exits, fire-fighting equipment, raising the alarm, making emergency plan, and limiting the spread of fire through compartmentation since fire in divided buildings seldom spread from one room to another. More importantly, life safety for all persons must be properly considered, planned, implemented and regularly checked. Escape routes, for instance, should be permanent, clearly identified, lead to a place of safety, well sing-posted and unobstructed. An effective fire safety plan including systematic evacuation procedures and installation of fire detecting and suppression devices can help residents achieved a fire safe home. The Report: 1.3 After examining the details of Mr. and Mrs. Jones house plan, a number of potential fire sources and risk points were found. In the Ground Floor: The external gas box located at the study and family room. The external electricity box Gas point at the utility room. Cooker in the kitchen and the kitchen itself may be considered a risk point. Fireplace at the lounge area. The CYL room situated in the third bathroom can be considered the only fire-starting place in the first floor. Positioning of Fire Alarms: 1.4 The positions of smoke alarms are all satisfactory but the device located at the ground floor is questionable. The power supply to smoke alarms is self-contained or battery powered. B1: Means of warning and escape: Fire detection and fire alarm systems: 2.1 There were adequate smokes alarms installed and are strategically located throughout the Jones’ house plan. Each storey has two fire alarms installed and they are located in the stairway hall, which is correct and compliant to fire safety standard or building regulation 2000. However, considering the location of the smoke alarm located in the ground floor, it has to remove or re-located since it is installed near and above the radiator. This is because air current produced by the radiator’s high temperature might push the smoke away from the smoke alarm. Smoke alarms should be installed in places that do not get very hot. This specification is clearly stated in the building regulation for smoke alarms. According to the plan, all fire alarms that will be installed in the Jones’ house are self-contained thus; they obtain power from a secondary power supply and can still operate in the event that the mains power failed. One very noticeable deficiency with the plan is it does not provide heat detectors for the kitchen and lounge room in spite of the fact that these rooms are potential fire starters. Basic fire equipment is essential to a home as smoke detectors, heat detectors, fire extinguishers, and escape ladders doubles the occupants chance of survival in the event of fire1. As a rule, a means of warning system should install throughout the dwelling with at least one alarm for each storey. Alarms must be sited in the circulation space within 7.5m of habitable rooms and more than 300mm from any walls or light fittings2 Means of escape: 2.2 The plan provides a suitable exit as rooms at ground and first floor have directly access to a hall leading to entrance D1-D2. Moreover, occupants of these rooms can have alternative means of escape since these rooms have windows that can be use when escape through the hall is not 1 J. Kolberg. Organize for Disaster: Prepare Your Family and Your Home for Any Natural Or Unnatural Disaster. Squall Press, US, 2005, p.54 2 Communities and Local Government. The Building Regulations 2000- Fire Safety: Approved Document B Volume 1: Dwellinghouses, The Stationery Office, UK, 2006. p. 16 possible. There is also one door located at rear elevation or D4 and another in the right side elevation that can be use as an exit in case of fire. In addition, all rooms in the first floor have immediate access to stairway hall, which is considered a protected stairway that is directly leading to the main entrance door. Some of the windows in the plan can be considered emergency egress windows such as W1, W4, W5, W7, and W8. However, although the height and width of these windows are more than 450mm, their clearance from the ground level is less than the standard 1100mm specified by Approved Document B. Although there are sufficient escape routes for other rooms mentioned earlier, the dressing room, bathroom, the shower room, and the master bedroom located in the first floor, which are considered inner rooms, do not have adequate and effective escape routes. Where possible, there should always be more than one exit route from a place of work. If the travel distance is more than 45 m to an exit, there must be two or more exits. This travel distance will vary depending on the risk rating of the site. If the number of exits cannot be improved, then the risk rating of the site for fire must reduced3. Except for kitchens, all habitable rooms in the upper storey of a house served by only one stair should be provided with a suitable window or external door. Any window of appropriate dimension and position may be an emergency egress window, not a just a roof window. A single egress window can be accepted to serve two rooms if both rooms have their own access to the stairs. A communicating door between the rooms must be provided so that it is possible to gain access to the window without passing through the stair enclosure. 3 P. Perry. Fire Safety Questions and Answers: A Practical Approach. Thomas Telford, UK, 2003, p.170 Where an emergency egress window is to be a roof window, the principle of self-rescue rather than ladder-assisted rescue should be held in mind. However, no maximum windows-to-eaves distance is indicated for a floor less than 4.5 metres above ground level4. To mitigate the risk, providing an alternative means of escape is necessary to comply with the means of escape provisions of the building regulations 2000. Since the rooms located in the first are affected by the problem, occupants should be provided with measures where it is possible to reach a place of relative safety. Since these rooms are not more than 4.5m above ground level, an emergency egress window should be provided. However, because self-rescue rather than a ladder-assisted is anticipated in two-storey dwelling, the thrust of the guidance is that an emergency egress window need to be accessible from the highway. Given that this is the case, the relationship between the depth of any enclosed space and the height of the building should be considered. Note that where a floor is more than 4.5 metres above ground level, pedestrian access is a requirement below the egress window. B2: Internal Fire Spread (linings): Walls and ceiling linings: 2.3 Although it is unlikely that it would start a fire, materials used in the construction of house can contribute to the rapid spread of fire. For instance, walls and ceiling materials can influence fires rate and speed of growth thus determining construction materials used for these internals linings is essential. However, if elements of construction such as walls, floor, beams, columns and doors, are to be provide effective barriers to fire spread and to contribute to the stability of 4 J. Coutts, Loft Conversions. Blackwell Publishing, UK, 2006, p. 50 building, they should be of a required standard of fire resistance5. After a thorough study of the Jones’ house plan and the materials to be use in its construction, it was determined that the plasterboards will be use for the lining of the wall and ceiling. The wall will be insulated from the inside so it can protect the other room from spread of fire and allow more time for occupant’s evacuation. Fire resisting capability of this insulation is around 30 minutes thus it will give enough time for responders to enter and suppress the fire. Accordingly, materials used in lining must be class C or higher and must conform to National (BS 476-7:1971, 1987, 1997) and European classification (BS EN 13591-1:2002). B3: Internal Fire Spread (Structure): Load bearing elements of structure: 3.1 It is widely recognized that fire can have significant effect that can cause structural failure. Some signs of weakening of load bearing of structural elements may be floors or rooflines bowing downward, indicating weakening columns, load-bearing walls, and other supports6 Buildings built with compartments separated by a wall or constructed to resist fire spread, can greatly minimize the effects and spread of fire inside a building. Fire comparmentation has been classically used to impede the spread of fires from one space to another7. The life safety approach is to buy time to enable people to get out of the building and by compartmentation; the threat of fire develops more slowly. 5 HUGHES, Phil and FERRETT, Ed. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate Butterworth-Heinemann, Italy, 2005, p.181 6 L. Collins, Technical Rescue Operations: Common Emergencies. PennWell Books, US, 2005, p.62 7 HARMARTY, T. Z. Fire Safety, Science and Engineering: A Symposium. ASTM International, US, 1985, p.312 Compartmentation helps the people by hindering the fire, allowing more time to escape8. Concealed Spaces (Cavities): 3.2 Cavities provides a good route for fire and smoke spread in a building thus it is essential that a 30 minutes fire resisting cavity barrier to be constructed. In the plan, wall cavities surround the Jones’ house. The space in the external walls, the areas around the window and door opening and the junction between the external and compartment wall, which are made of bricks and block, forms these cavities. Every cavity barrier as specified in Approved Document B9 for construction and fixings for cavity barriers should be constructed to provide at least 30 minutes resistance. Cavity barriers in a stud wall or partition or those provided around openings should consist of steel of at least 0.5mm thick, a timber of at least 38mm thick, polythene-sleeve mineral wool, or calcium silicate, cement-based or gypsum-based boards at least 12mm thick. A cavity barrier should, wherever possible, be tightly fitted to a rigid construction and mechanically fixed position to ensure that their performance is unlikely to be made ineffective by a movement of the building to subsidence, shrinkage or temperature change. Moreover, it should not be affected movement of the external envelope due to wind, collapse in fire of any services penetrating them, and failure in a fire of their fixings10. However, the Jones’ house plan did not include or specify details of the cavity barrier. 8 E. Reid . Understanding Buildings: A Multidisciplinary Approach. MIT Press, US, 1988, p.179 9 COMMUNITIES AND LOCAL GOVERNMENT, The Building Regulations 2000- Fire Safety: Approved Document B Volume1: Dwellinghouses, The Stationery Office, UK, 2006, p.36 10 R. Tricker and R. Algar, Building Regulations in Brief. Butterworth-Heinemann, UK, 2007, p.468 Protection of opening and fire stopping: 4.1 Proprietary fire-stopping and sealing systems that passed a test for maintaining fire resistance walls may use as fire-stopping materials. For instance: cement mortar, gypsum-based plaster, cement-based or gypsum-based vermiculite/perlite mixes, glass fibre, crushed rock, blast furnace slag, or ceramic-based products, and intumescent mastics. A fire retardant’s purpose is to slow the spread of flame and lower smoke development11. However, not all of them will be suitable in every situation12. Fire stopping is required in concealed vertical spaces in walls and partitions at each floor level and at the ceiling of the uppermost story13. B4: External fire spread: Construction for external walls: 4.2 As a requirement of Approved Document B (Part B of Schedule 1 to the Building Regulations 2000-as amended), external walls of a building should adequately resist the spread of fire over the walls and to another building14. The extents to which an external wall can limit the risk of a fire spreading from the building and beyond its boundaries depend on the use of the building, its distance from the boundary, and height. 11 J. Klosowski and J. Myers. Science and Technology of Building Seals, Sealants, Glazing, and Waterproofing: Seventh Volume. ASTM International, US, 1999, p. 268 12 COMMUNITIES AND LOCAL GOVERNMENT, The Building Regulations 2000- Fire Safety: Approved Document B Volume 1: Dwellinghouses, The Stationery Office, UK, 2006, p.40 13 H. Harrison. Houses: The Illustrated Guide to Construction, Design and Systems. Dearborn Real Estate, US, 1998, p.232 14 STATIONERY OFFICE, Building Regulations Approved Document B: Approved Document, B: Fire Safety, Vol. 1: Dwellinghouses: B1 Means of Warning and Escape; B2 Internal Fire Spread (linings); B3 Internal Fire Spread (structure); B4 External Fire Spread; B5 Access and Facilities for the Fire Service. The Stationery Office, UK, 2007, p.20 The Jones’ house plan indicates that bricks will be the material for the externals walls, which is a good approach since bricks are considered a good heat insulator. Limiting the size of unprotected areas in all sides of a building is very essential since an external wall that do not have adequate fire resistance or its fire resistance rating is below standards then that area can be considered unprotected. Similarly, an external wall, which has adequate fire resistance but contains more than 1mm thick of combustible material B5: Access and facilities for the fire and rescue service: Vehicle Access: 4.3 Vehicles particularly fire fighting appliance should have access to the exterior of a building to enable high reach equipments such as turntable ladders and hydraulic platforms to be used and to make fire fighting search and rescue activities more convenient. For this reason, it is always necessary to a have 45-metre vehicle access for a fire fighting appliance to all sides of the building. In addition, suitable doors not less than 750mm should be provided to give fire fighters access to the interior of the building. However, there should be no more than 60 metres between each door15. In Jones’ house plan, the doors D1-D2 provide accesses in the interior of the house and they measure about 990mm, which is satisfactory and compliant to the 750mm regulation. 15 COMMUNITIES AND LOCAL GOVERNMENT, The Building Regulations 2000- Fire Safety: Approved Document B Volume 1: Dwellinghouses, The Stationery Office, UK, 2006, p.19 Conclusion: 4.4 The house plan for Mr. and Mrs. Jones met some of the requirements of fire safety regulations. The doors and windows satisfactorily met the required specifications of Approved Document B as alternative and appropriate exits. However, there are some deficiencies that need to be address such as the location of smoke alarms and heat detectors. Moreover, the plan should consider the fire resisting capability of the internal wall such as those near the kitchen and the lounge. Overall, the design Mr. and Mrs. Jones house can be considered satisfactory as far as means of escape, vehicle access, materials of external walls, and placement of the majority of fire and smoke alarms. However, the design should reconsider the deficiencies before construction. Recommendations: 5.1 As mentioned earlier, deficiencies should be reconsider thus changes in the placement of smoke alarms near the stairway near the ground floor is recommended. More importantly, heat detectors should be installed in the kitchen and lounge to reduce the risk of fire occurring in these rooms. Installation of heat detectors in the kitchen is preferable that smoke detectors because grease particles and smoke will not set it off. Heat detectors works best if installed in the basement near the furnace or water heater, in the kitchen, in the garage, and in other areas where dust, grease, smoke or fumes might set off a smoke detector. Similarly, the kitchen’s walls and doors should fire resistant to keep fire from spreading into the other rooms. It is also recommended the installation of emergency lighting particularly in the circulations space to give occupants clear view in case of power failure or evacuation due to fire. Lastly, fire-stop should be provided on extract fans located at the wall between the kitchen and the utility room to prevent fire spread. 6.1 References: COLLINS, Larry, Technical Rescue Operations: Common Emergencies. PennWell Books, US, 2005 COMMUNITIES AND LOCAL GOVERNMENT, The Building Regulations 2000- Fire Safety: Approved Document B Volume 1: Dwellinghouses, The Stationery Office, UK, 2006 COUTTS, John, Loft Conversions. Blackwell Publishing, UK, 2006 HARMARTY, T. Z. Fire Safety, Science and Engineering: A Symposium. ASTM International, US, 1985 HARRISON Henry S. Houses: The Illustrated Guide to Construction, Design and Systems. Dearborn Real Estate, US, 1998 HUGHES, Phil and FERRETT, Ed. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate Butterworth-Heinemann, Italy, 2005 KLOSOWSKI, Jerome M. and MYERS, James C. Science and Technology of Building Seals, Sealants, Glazing, and Waterproofing: Seventh Volume. ASTM International, US, 1999 KOLBERG, Judith. Organize for Disaster: Prepare Your Family and Your Home for Any Natural Or Unnatural Disaster. Squall Press, US, 2005 PERRY, Pat. Fire Safety Questions and Answers: A Practical Approach. Thomas Telford, UK, 2003 REID, Esmond . Understanding Buildings: A Multidisciplinary Approach. MIT Press, US, 1988 STATIONERY OFFICE, Building Regulations Approved Document B: Approved Document, B: Fire Safety, Vol. 1: Dwellinghouses: B1 Means of Warning and Escape; B2 Internal Fire Spread (linings); B3 Internal Fire Spread (structure); B4 External Fire Spread; B5 Access and Facilities for the Fire Service. The Stationery Office, UK, 2007 TRICKER, Ray and ALGAR, Rozz, Building Regulations in Brief. Butterworth-Heinemann, UK, 2007 Read More