Building Design in the Context of Fire Safety - Assignment Example

1. Give a definition of fire, include an appropriate diagram A standardized definition of fire is that it is a procedure of incineration distinguished by the discharge of heat convoyed by smoke or flame. The origination of fire is resulted from the amalgamation of heat, oxygen and flammable substances. 2. Identify the different stages of fire growth, include an appropriate diagram There are six stages of fire growth, which are as follows: Incipient phase Growth phase Flashover phase Fully-developed phase Decay Phase Extinction phase 3. Explain the difference between pre-mixed and diffusion flames, and provide some practical examples of each When the flammable molecules enclose the element carbon, then the yellow spot can be possibly observed in the diffusion flames whereas in pre-mixed flames, they are not yellow except in the situation when they are tremendously loaded of flammable substances. In premixed flames the oxygen exists in appropriate amounts in addition with the burnable substances. 4. What are the 5 functional requirements of Approved Document B? The five functional requirements of Approved Document B are as follows: 1) As per the requirements of the Approved Document B it is must for the architect to plan and design a structure in a manner that it should comprises of ample necessities like early conflagration caution apparatuses and proper, secure and efficient evacuation passages. 2) To control the intensification of inferno in the interior of a structure it is necessary to utilize the material that can bear and defy the blazes distribution over it and in case it catches fire, there should be a sluggish rate of temperature release, reasonable as per situation 3) The indoors are ought to be constructed in a way that in case of fire it is supposed to be steady for the utmost period and it must defend against the fire dispersion among two buildings with an tolerable system for the smoke discharge 4) The outside walls and roof of construction must defend against the fire to reach over from a construction to any more having stared to operation, height and pose. The blueprint of structure must be well architected to ease fire-fighters in shielding lives 5) It is required for a structure to bequeath with openhanded space to assist the access of fire equipments into the structure. 5. There are two broad standards for the design methods of fire resistance of buildings: prescriptive and performance-based. Explain the difference between them A performance oriented process for structural inferno design is akin to the modus operandi of devious structures to wind masses and seismic effects. The role of a structural component will be definite and a set of objective tests will be prearranged that allocates the assessment of fire recital in relation to the key practical decisive factor on the other hand, Prescriptive method characterizes a structural conflagration design moderately accurate in requisites of the resources involved, contour and extent of structural rudiments, depth of fire safety materials and construction detail etc. The design proposals are mostly based on the practice with matching or analogous standard inferno tests. 6. What are the two categories of fire testing? Explain the difference between them There are two major categorical methods of fire testing : 1. Combustibility test – test to assess the combustibility properties of materials to be used in the building. 2. Exposure period test – in this test a curve is maintained to demonstrate the time taken by a material to reach its maximum limit before losing its integrity. 7. Why is it important to carry out more than one experiment to test the same parameter? It is necessary to carry out more than one test for a specific perimeter in array to verify the results obtained from the previous test as in earlier investigations by experts it is revealed that the same perimeter can possibly respond diversely during different tests. It is also done to acquire more realistic results. 8. What factors influence the severity of a fire within a compartment? There are a number of factors which influence the severity of fire with in a compartment: Fuel load Smoke load Thermal output Air supply Dimensions of windows Size of compartment 9. How is heat transferred in a compartment fire? Include a diagram In a compartment there are two possible ways through which heat can be transferred – Conduction and Radiation. Conduction is a transport of molecular energy requiring a matter to get transferred while radiation is electromagnetic energy transfer because of possession of thermal energy in a body 10. Explain the term “flammability limits The term “Flammable limits” usually relate to gaseous fumes and are explained as the concentration series in which a inflammable matter is capable to turn out a fire when an detonation source is in attendance. The concentration is commonly articulated as percent gaseous energy by size. 11. Draw a graph/ diagram to illustrate the flammability limits of flammable vapors. 12. Define the term “limiting oxygen index”. The “Limiting Oxygen Index” is the majority of normally conducted studies and renowned organization technique to substantiate the proportional blazing power of “inflammable resources.” An arithmetical manifestation, the “LO”’, is moreover characterized as the slightest attentiveness of oxygen in “oxygen – nitrogen mixture,” obligatory to support up downward flaming of an upright mounted test sample. 13. What does it mean if a sample has a high LOI or a low LOI If a sample has a high LOI then it is considered to contain better fire resistance properties whereas if a sample turns out to be having low LOI than it is considered to have less fire resistance power. The LOI test is conducted to assess the inflammable behavior of the substances to be utilized. 14. Explain the ignitability test? The ignitability test is a very popular test to evaluate the uncomplicatedness of a substance bursting potential into flames once exposed to a diminutive flame like of a matchstick. The blistering of the model is then observed for fire spread and the velocity of particles on fire and fire drops. The testing report incorporates data knowledge relating to the previous experiment samplings and experiment conclusions. 15. The cone calorimeter can be used to measure a number of different parameters from experimental fires, what are they and which one is the most important in determining the fire hazard performance of materials? 16. What are the criteria for when flashover will occur? The flashover is the reaction chained by the emission reaction of temperature. Flashover takes place when an ample amount of energy from the increasing fire starts collecting into the upper walls and cavities of the room, heating up the burnable gases to their ignition level and leading them to their “auto-ignition temperature.” This collection of rapid moving thermal power in the compartment triggers the flashover. The two criteria of flashover are “Heat assorted with Smoke and overturn.” 17. Once ignition has occurred what is required to maintain combustion? Once ignition has occurred a regular flow of air and constant pressurized supply of fuel is necessary to maintain the process of combustion. 18. What are the basic two types of uncertainty found in measurements? Give an example of each. The two categories of fire testing are: Tests to estimate detonation and the stretch of conflagration in a precise area and Tests to calculate the fire conflict power. The main disparity between the set of two methods are fire confrontation tests weigh up a substance’s competence to keep it up to uphold its formation for the interval of a fire while, the Tests conducted to measure ignition timing and blazes distribution concludes the instance taken by the flames to explode and reach in a specific room. 19. Presented below are 10 heat release rates for a piece of laminated wood at 25.00kW/m2. Calculate the range, the mean, the standard deviation and then the uncertainty in the mean and the uncertainty in the standard deviation. Test 1 2 3 4 5 6 7 8 9 10 Heat Release Rate @ 25.00kW/m2 44.80 42.15 42.97 43.60 43.88 44.80 42.79 45.10 41.62 43.74 20. In the table below there is a set of results obtained from the “Bang Box” experiment. Plot a graph which will best show your results and state what the results show. Fuel Acetone Test 1 Test 2 Test 3 Test 4 Test 5 Test 6 Test 7 Test 8 Number of Drops 2 6 10 12 14 16 18 20 Height attained by lid (cm) 0 20 40 80 120 150 110 90 21. What are the four main classes of ignition? The four main classes are: Ignition source The material first ignited The oxidizer present The ignition factor 22. In relation to the characteristics of building materials give definitions for the following terms: Combustibility - The propensity of a substance to catch fire is known as combustibility. It is experienced by introduction of a small sample of substance in an oven (typically at 750°C) and then to examine its temperature increase. A matter is definite as inflammable if it raises the hotness of the oven interior by 30 degrees or more when it completely burns up. Fire propagation – Fire resistance - Any material that means the substance or substrate hold backs or resists blazing: though it will flame ultimately. Surface spread of flame – 23. Explain what the two major mechanisms of burning are The two major mechanisms of burning are: 1. Gas phase flaming combustion 2. Glowing combustion 24. How can fire spread between buildings There are two ways in which fire is possible to spread between two buildings, which are: a. By the uncontrolled blazes from a conflagration in one structure unswervingly impugning on an adjoining building, or b. Via radiated heat from the structure on fire igniting the adjoining building. 25. Define the term “fire plume”. Identify and explain the different regions within a fire plume. Read More