5 FIRE SAFETY PRINCIPLES - architecture design
- 2. The Fire Triangle: Three elements - fuel, oxygen and heat - are required to start a fire. The oxidation process will not be possible without any one of these elements. Fuel (Fire Load) Oxygen (Ventilation) Heat (Ignition) Fire is a rapid oxidation process accompanied by the evolution of heat, light, flame and the emission of sound. Definition and Causes of Fire 2 Intro
- 3. Ordinary combustible materials such as wood, cloth, paper, rubber and plastics, etc. Class A: Flammable or combustible liquids, flammable gases. Class B: Energized electrical equipment Class C: Fire involving: Combustible metals such as potassium, sodium, magnesium and other reactive metals Class D: How to Suppress: Use Water Exclude air from burning materials No Water; Use electrically non-conductive extinguishing agents such as gaseous systems Heat-absorbing medium which is not reactive with burning metals Intro Classes of Fire 3
- 4. Intro Fire Growth 2 Pre-flashover or growth phase Stage 1: Flashover Stage 2: Fully developed fire (Stable phase) Stage 3: Decay (Cooling Period) Stage 4: Involves flaming combustion of an item and may lead to a spread of fire; or a smoldering, poorly- ventilated fire with substantial smoke. Rapid change from a local fire to one involving all combustible materials in a room. All materials in compartment are alight; maximum rate of heat release is dependent on either available ventilation or quantity of fuel. Gradual consumption of fuel in the compartment. Stages
- 5. Stage 1 Stage 2 Stage 3 Stage 4 Active Fire Protection Detection, activation and suppression Passive Fire Protection Resistance to heat and flames of fire rated constructions Temperature Time Slow rate of burning Development of heat and flames Load bearing capacity of materials is maintained. Prevention of fire spread to other compartments. This graph shows where active and passive fire protection will play an important part during the development of fire. Intro Fire Growth 2 Architectural Intervention during Fire Growth
- 6. Behavior of Fire and Smoke 1 Vertical Shaft or Duct (Stack Effect) Suspended Ceiling Ceiling Void Smoke and Flame likely to re-enter Enclosed Area Vertical Shaft or Duct Outlet to adjoining space Enclosed Area Outlet to open air 1.00 m Intro
- 7. Internal Fire Spread due to: Internal Fire Spread between Rooms and Floors Through Vertical Shafts Through Air Ducts Through Ceiling and Collapsed Partitions Through Non-Fire Rated Doors Origin of Fire Fire Spread 2 Intro
- 8. Fire Spread Congested High Fire Load Areas External Fire Spread due to: Intro
- 9. Fire Spread External Fire Spread due to: Intro Loss of Integrity of Fire Wall
- 10. Fire Spread 2 Ignition of Materials Ignition of Materials Ignition of Materials Ignition of Materials Convection Currents Origin of Fire Proximity of Buildings Intro External Fire Spread due to:
- 11. Aims in Fire Safety Design A To prevent fire B To safeguard the lives of occupants and firefighters C To reduce damage on the building, its contents, and on surrounding buildings
- 12. Basic Principles 1 Fire Avoidance 2 Fire Detection 3 Fire Growth Restriction 4 Fire Containment 5 Fire Control 6 Smoke Control 7 Escape Provisions
- 13. Definition & Implication Principles Fire Avoidance1 1 Reducing the possibility of accidental ignition of construction materials, as well as fittings and fixtures. This implies: a. keeping separate heat sources and materials which might ignite readily through proper planning and zoning b. need to specify materials to reduce the risk of fire starting c. reducing fire load Basic
- 14. Principles Fire Avoidance1 1 For Hospitals (eg. Hospitals) Fire Zoning Basic For Most Buildings 1. Life Risk Areas – areas in which all occupants are ambulant and able to move unaided away from a fire - eg. Outpatient department; Service Zone 2. High Fire Risk Areas – areas which, due to their function, are more usually susceptible to an outbreak of fire, or to a rapid spread of fire or smoke. - eg. Kitchen or Boiler Room 3. High Fire Load Areas – areas which, because of their construction or contents, contain large amounts of combustible materials, thereby constituting a fire load in excess of that normally found - eg. Gas Storage, Linen Closets 4. High Life Risk Areas – areas in which persons may reside and are not able to move unaided away from a fire. - eg. Intensive Care Unit, Operating Department
- 15. LEGEND: HIGH LIFE RISK HIGH FIRE LOAD HIGH FIRE RISK Basic Principles (eg. Hospitals) Fire Zoning Fire Avoidance1 LIFE RISK
- 16. Choice of Materials and Knowledge on Material Performance 1 Steel - does not burn - may buckle in fire - high conductivity spreads heat - loses half its strength in 550°C Timber - combustible - little loss of strength as charcoal formed insulates wood core - spreads flames Masonry - high fire resistance - cracks at 575°C - are subject to high temperatures during manufacture Calcium Silicate - excellent thermal shock resistance - up to 1000°C - suitable for cladding structural members Glass - standard float, toughened and laminated glass panes do not provide any fire resistance - monolithic fire-rated glass is available Basic Principles Fire Avoidance2 1 Concrete -high fire resistance - disintegrates at 400-500°C - holes in concrete will expose steel structural members
- 17. “the amount of material which is able to burn and release heat and smoke” In a compartment, limiting fuel will help reduce the dangers of heat and smoke. Building contents make up the majority of the fire load, since most fires start from the ignition of these contents. The total amount of fuel in a building, its accessibility to fire engines, the availability of water, etc. will determine the level of fire resistance and the maximum size of a building compartment. Basic Principles Fire Avoidance2 1 Knowledge on Fire Load 1
- 18. Visual Fire Detection To visually expose FIRE RISK and FIRE LOAD areas to building occupants. Basic Principles Patient Room Nurse Station Patient Room Sto 2 Fire Detection Lounge
- 19. fire-prone areas should be visually accessible provide peepholes on doors Basic Principles Visual Fire Detection 2 Fire Detection
- 20. Makes use of manual and automatic (electric/ electronic) methods of informing the occupants in charge that a fire has occurred in a given location. Heat and smoke alarm systems inside Fire Risk and Fire Load areas. Basic Principles Mechanical Fire Detection 2 Fire Detection Fire alarm systems must be accessible in all zones especially in fire-prone areas.
- 21. Aimed at ensuring that the growing fire is extinguished immediately and at providing adequate time for firemen to arrive, control the fire and evacuate the occupants. Basic Principles Actively extinguishing or slowing down the development of a fire before the full involvement of the room. This is done by the room’s local occupants. Means: 1. Fire Extinguisher 2. Water Supply 3. Fire Blanket 4. Bucket of Sand 3 Fire Growth Restriction Manual Means of Restricting Fire Growth 5
- 22. Basic Principles 3 Fire Growth Restriction Rating of Fire Extinguishers 4 : Class A Extinguishers will put out fires in ordinary combustibles, such as wood and paper. The numerical rating for this class of fire extinguisher refers to the amount of water the fire extinguisher holds and the amount of fire it will extinguish Class B Extinguishers should be used on fires involving flammable liquids, such as grease, gasoline, oil, etc. The numerical rating for this class of fire extinguisher states the approximate number of square feet of a flammable liquid fire that a non-expert person can expect to extinguish Class C Extinguishers are suitable for use on electrically energized fires. This class of fire extinguishers does not have a numerical rating. The presence of the letter “C” indicates that the extinguishing agent is non-conductive Class D Extinguishers are designed for use on flammable metals and are often specific for the type of metal in question. There is no picture designator for Class D extinguishers. These extinguishers generally have no rating nor are they given a multi-purpose rating for use on other types of fires
- 23. Basic Principles 3 Fire Growth Restriction Types of Fire Extinguishers 4 : Dry Chemical extinguishers are usually rated for multiple purpose use. They contain an extinguishing agent and use a compressed, non-flammable gas as a propellant Halon extinguishers contain a gas that interrupts the chemical reaction that takes place when fuels burn. These types of extinguishers are often used to protect valuable electrical equipment since them leave no residue to clean up. Halon extinguishers have a limited range, usually 1.2 to 1.8 meters. The initial application of Halon should be made at the base of the fire, even after the flames have been extinguished Carbon Dioxide (CO2) extinguishers are most effective on Class B and C (liquids and electrical) fires. Since the gas disperses quickly, these extinguishers are only effective from 1.0 to 2.4 feet. The carbon dioxide is stored as a compressed liquid in the extinguisher; as it expands, it cools the surrounding air. The cooling will often cause ice to form around the “horn” where the gas is expelled from the extinguisher. Since the fire could re-ignite, continue to apply the agent even after the fire appears to be out
- 24. Basic Principles -Categories: General Use, Institutional, Residential, Attics, Special Hazards, Storage -3 heads: upright, pendent and sidewall -Rated to 175 psi 3 Fire Growth Restriction Mechanical Means of Restricting Fire Growth 6 Sprinkler Specifications: Sprinklers can be spaced from 3.6 to 6.0 meters apart.
- 25. Assumes that measures to control a growing fire may not be successful, hence its maximum size needs to be restricted both to reduce the risk and to allow effective firefighting. Extend CHB walls up to slab Provide 1 m. ledge to prevent spread of fire - providing a 1-meter ledge to prevent fire from creeping up exterior walls into the floor above through windows. This implies: 1. Fire cladding of structural components to ensure stability of structural frames. 2. The use of fire-rated walls and slabs to contain fire in rooms, sub-compartments and compartments so as to segregate areas where fire may occur. 3. Others: - plugging all holes; extending CHB walls up to the slab; Basic Principles 4 Fire Containment Definition and Implication
- 26. Fire-Rated Surface Compartment Compartment Sizes The more combustible the contents of a building, the smaller the compartment should be. Joints must be filled with non-combustible materials to prevent the spread of smoke or flame. Objectives -To limit fire and smoke spread -To allow longer escape time -To reduce the maximum potential size of the fire Containing fire- prone areas by means of fire- resistive enclosures Definition Basic Principles 4 Fire Containment Sub-Compartment Concepts of Fire Compartmentation 2 Room
- 27. Basic Principles 4 Fire Containment Concepts of Fire Compartmentation LEGEND: Rooms Department
- 28. Basic Principles 4 Fire Containment Fire Rating of Construction Systems 3 Gypsum Walls -Two layers 16mm type X gypsum wallboard or veneer base applied to each side of 62mm metal studs 400mm O.C. -Two layers 16mm type X gypsum wallboard or veneer base applied to each side of 50mmx100mm wood studs 600mm O.C. -One layer 16mm type X gypsum wallboard or veneer base applied to each side of 40mm metal studs 600mm O.C. -One layer 12mm type X veneer base nailed to each side of 50mmX100mm wood studs 400mm O.C. Steel Wood Steel Wood 2 Hour 1 Hour Concrete Masonry Wall Units 4 Hour 2 Hour 4” 6”
- 29. Basic Principles 4 Fire Containment Fire Rating of Construction Systems 3 Ceiling Systems 12mm gypsum wallboard applied to drywall furring channels. Furring channels 600mm O.C., attached with 18 gauge wire ties open web steel joists 600mm O.C. supporting rib metal lath on 28 gauge corrugated steel and 62mm concrete slab. 12mm gypsum wallboard applied to drywall resilient furring channels 600mm O.C. and nailed to wood joists 400mm O.C. Wood joists supporting 25mm T&G finish floor. 3 Hour 2 Hour 1 Hour 12mm 25mm STEEL RUNNERS 3-16mm FIRE RATED PANELS 35mm x 22mm ANGLE RUNNER CORNER REINFORCEMENT WIRE MESH
- 30. Basic Principles 4 Fire Containment Fire Rating of Construction Systems 3 -Flush Metal Door -No Glass Permitted -3mm clearance at jambs -10mm clearance at non-combustinle floor -For openings in fire walls or walls that divide a single building into fire areas -Maximum glass area 0.063 sq.m -6mm thk Wire glass in a steel frame -For openings in enclosures of vertical communications through buildings and in 2-hour rated partitions providing horizontal fire separations -Maximum glass area: 0.83 sq.m -For openings in walls or partitions between rooms and corridors having a fire resistance rating of 1 hour or less 3 Hour 2 Hour 1 Hour Door Openings For 1.2m X 3.0m single hollow metal doors (ga.20 steel face), with labeled single-point or 3-point latching hardware, steel hinges or pivots 1.370m max 0.83m max 125mm min 125mm min
- 31. *Insulated building elements will not ignite in fire and will ensure passage of human beings without damage on the other side of the separating element. Ability to prevent heat transfer from one face to the other face. Insulation Temperature increase Load Bearing Capacity Collapse or excessive deflection Structural Performance: Building still stands during an emergency Ability to carry load without collapsing Integrity Passage of flame Ability to resist the development of crack or perforations so as not to allow passage of smoke and flame Basic Principles 4 Fire Containment Load Bearing Capacity, Integrity and Insulation 2
- 32. Covers those devices and systems which aid firefighters in actively extinguishing the fire and bringing it to an end earlier than a free-burning fire. ensure that all areas inside and outside the building are covered by reach of the firehose Basic Principles 5 Fire Control Definition and Implication access road for firetrucks Access Road
- 33. Basic Principles 5 Fire Control Fire apparatus should have unobstructed access to buildings. R L W Bollards and fences used for traffic control must allow for sufficient open road width for fire truck Site Access for Fire Control8: 30m> DEAD END CUL-DE-SAC T-TURN Prevent time-consuming, hazardous back-ups at dead-ends by using T- turns and cul-de-sacs MAX. 90 METERS FIRE HYDRANT Place hydrants at max. 3 meters from curb. Siamese connection to standpipes must be visible and within 60m from hydrant SIAMESE CONNECTION Utility poles, kiosks, sculpture, fountains, plant boxes can impede fire rescue operations 0.3m Hydrant must be unobstructed; Fire hose connection should be at least 0.3m above grade
- 34. Basic Principles 5 Fire Control Firetrucks 75 ° (safe angle) 30 m. Approx. 10 storeys 8.5 m. 75 ° 25 m. Approx. 8-9 storeys 6.7 m. 75 ° 20 m. Approx. 6-7 storeys 5.6 m. Aerial Apparatus Specifications:
- 35. Provides access to a building, especially in high rise buildings, for fire brigades. Is fully-equipped with firefighting equipment, service elevator, stair and lobby. Provides a sufficiently secure operating base and a rest area in between firefighting operations. Wet and Dry Risers Elevator shaft Fire-rated doors Basic Principles 5 Fire Control Concept of the Firefighting Shaft
- 36. Measures which can assist to some extent occupants in the fire zone but are particularly needed for others in adjacent areas or compartments. Techniques of Smoke Control a. SMOKE CONTAINMENT/ BARRIER – technique of restricting the movement of smoke by the provision of fire resisting elements. b. SMOKE DISPERSAL – technique of clearing smoke locally by provision of natural cross-ventilation or mechanical venting. Make Up Air Smoke Barrier Smoke Plume Shop Mall Basic Principles 6 Smoke Control Definition and Techniques 2 Venting Extraction of Smoke Ceiling Reservoir
- 37. Low Pressure High Pressure Uses barriers including walls, floors and doors, to contain pressurized air generated by mechanical means to keep smoke away from protected areas such as escape staircases and corridors. c. PRESSURIZATION – technique whereby air is blown into spaces which are designed to be kept clear of smoke. Basic Principles 6 Smoke Control Definition and Techniques 2
- 38. Cover a range of passive or active systems which permit the occupants to move or be moved to a place of safety within or to the outside of a building. FIRE ESCAPE: fire escape stairs designed to be used daily for familiarity of escape route well-maintained (not used as storage of junk) CORRIDOR SYSTEM: direct, not tortuous simple lay-out no barriers, cul-de-sacs, bottlenecks doors open out, not in easily detectible, not hidden from view Basic Principles 7 Escape Provisions Definition
- 39. Escape Route Leading to: Place of Safety Place of Safety Stairway Enclosure c. Protected Stairway Enclosure Place of Safety Place of Safety Protected Escape Route a. Protected Escape Route Place of Safety Place of Safety Protected Lobby b. Protected Lobby To provide safety, the routes must be properly protected from the effects of fire and smoke for an acceptable time period, usually a minimum of 60 minutes. This can be achieved by: - Compartmentation - Fire resistance of escape route structure - Use of smoke control systems to keep smoke out of escape routes Protected escape routes are designed in such a way that they lead to a place of safety, and once inside the occupants are safe from the immediate danger from fire and smoke. Basic Principles 7 Escape Provisions Protected Escape Routes 1
- 40. Access through Courtyards exit courtyard Alternative Means of Escape -Doors should be as far as possible from each other; preferably on opposite walls -Both doors should not open into the same compartment compart- ment courtyard subcomp- artment subcomp- artment subcomp- artment subcomp- artment Place of Safety Place of Safety Basic Principles 7 Escape Provisions Alternative Means of Escape 1
- 41. Reqd. width of escape route Additional width to allow for door swing Design width Design width 90° min 90° min Basic Principles 7 Escape Provisions Design of Fire Resisting Doors 1
- 42. 1. The presence of patients with various degrees of dependency and immobility on one hand and the constant presence of staff on the other. 2. It is assumed that there should be no reliance on external; rescue or such manipulative types of escape appliances as chutes or fire ladders. 3. The staff would be fully responsible in assisting patients within their area of control to a place of safety in an emergency. Basic Principles 7 Escape Provisions Primary Considerations in the Design for FIRE Safety of Hospitals1
- 43. Basic Principles 7 Escape Provisions Progressive Horizontal Evacuation 1