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Smoke Explosion
A backdraft (North American English) or backdraught (British English) is the abrupt burning of superheated gasses in a fire, caused when oxygen rapidly enters a hot, oxygen-depleted environment; for example, when a window or door to an enclosed space is opened or broken. Backdrafts present a serious threat to firefighters. There is some debate concerning whether backdrafts should be considered a type of flashover (see below). Burning When material is heated enough, it begins to break down into smaller compounds, including hydrogen. This is called pyrolysis, and does not require oxygen. If oxygen is also provided, then the hydrogen can combust, starting a fire. If material undergoing pyrolysis is later given sufficient oxygen, the hydrogen gas will ignite, and therefore, combustion takes place. Cause A backdraft can occur when a compartment fire has little or no ventilation. Due to this, little or no oxygen can flow into the compartment. Then, because fires reduce oxygen, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American English
North American English (NAmE, NAE) is the most generalized variety of the English language as spoken in the United States and Canada. Because of their related histories and cultures, plus the similarities between the pronunciations (accents), vocabulary, and grammar of American English and Canadian English, the two spoken varieties are often grouped together under a single category. Canadians are generally tolerant of both British and American spellings, with British spellings of certain words (e.g., ''colour'') being favored in more formal settings and in Canadian print media; for some other words the American spelling prevails over the British (e.g., ''tire'' rather than ''tyre''). Dialects of American English spoken by United Empire Loyalists who fled the American Revolution (1775–1783) have had a large influence on Canadian English from its early roots. Some terms in North American English are used almost exclusively in Canada and the United States (for example, the term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flammability Limit
Mixtures of dispersed combustible materials (such as gaseous or vaporised fuels, and some dusts) and oxygen in the air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to as flammability limits or explosive limits. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air (the stoichiometric proportion) is important in internal combustion engines such as gasoline or diesel engines. The standard reference work is still that elaborated by Michael George Zabetakis, a fire safety engineering specialis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firefighting
Firefighting is the act of extinguishing or preventing the spread of unwanted fires from threatening human lives and destroying property and the environment. A person who engages in firefighting is known as a firefighter. Firefighters typically undergo a high degree of technical training. This involves structural firefighting and wildland firefighting. Specialized training includes aircraft firefighting, shipboard firefighting, aerial firefighting, maritime firefighting, and proximity firefighting. Firefighting is a dangerous profession due to the toxic environment created by combustible materials, with major risks are smoke, oxygen deficiency, elevated temperatures, poisonous atmospheres, and violent air flows. To combat some of these risks, firefighters carry self-contained breathing apparatus. Additional hazards include falls — a constant peril while navigating unfamiliar layouts or confined spaces amid shifting debris under limited visibility – and structural collapse t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Protection
Fire protection is the study and practice of mitigating the unwanted effects of potentially destructive fires. It involves the study of the behaviour, compartmentalisation, suppression and investigation of fire and its related emergencies, as well as the research and development, production, testing and application of mitigating systems. In structures, be they land-based, offshore or even ships, the owners and operators are responsible to maintain their facilities in accordance with a design-basis that is rooted in laws, including the local building code and fire code, which are enforced by the authority having jurisdiction. Buildings must be constructed in accordance with the version of the building code that is in effect when an application for a building permit is made. Building inspectors check on compliance of a building under construction with the building code. Once construction is complete, a building must be maintained in accordance with the current fire code, which is e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products. At a certain point in the combustion reaction, called the ignition point, flames are produced. The ''flame'' is the visible portion of the fire. Flames consist primarily of carbon dioxide, water vapor, oxygen and nitrogen. If hot enough, the gases may become ionized to produce Plasma (physics), plasma. Depending on the substances alight, and any impurities outside, the color of the flame and the fire's Intensity (heat transfer), intensity will be different. Fire in its most common form can result in conflagration, which has the potential to cause physical damage through burning. Fire is an important process that affects ecological systems around the globe. The positive effects of fire include stimulating growth and maintaining various ecological systems. Its negative effects include hazard to life and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, and highly combustible. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all normal matter.However, most of the universe's mass is not in the form of baryons or chemical elements. See dark matter and dark energy. Stars such as the Sun are mainly composed of hydrogen in the plasma state. Most of the hydrogen on Earth exists in molecular forms such as water and organic compounds. For the most common isotope of hydrogen (symbol 1H) each atom has one proton, one electron, and no neutrons. In the early universe, the formation of protons, the nuclei of hydrogen, occurred during the first second after the Big Bang. The emergence of neutral hydrogen atoms throughout the universe occurred about 370,000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrolysis
The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''pyro'' "fire", "heat", "fever" and '' lysis'' "separating". Pyrolysis is most commonly used in the treatment of organic materials. It is one of the processes involved in charring wood.''Burning of wood'' , InnoFireWood's website. Accessed on 2010-02-06. In general, pyrolysis of organic substances produces volatile products and leaves , a carbon-rich solid residue. Extreme pyrolysis, which leaves mostly |
Before Crime * After Days (BP), a timescale used mainly in geo ...
Before is the opposite of after, and may refer to: * ''Before'' (Gold Panda EP), 2009 * ''Before'' (James Blake EP), 2020 * "Before" (song), a 1996 song by the Pet Shop Boys * "Before", a song by the Empire of the Sun from ''Two Vines'' * "Before", a song by Anastacia from ''Evolution'' * "Before" (short story) by Gael Baudino * The Before film trilogy by Richard Linklater ** ''Before Sunrise'', 1995 ** ''Before Sunset'', 2004 ** ''Before Midnight'' (2013 film) See also *Before Christ (BC), an epoch used in dating years prior to the estimated birth of Jesus *Before Common Era (BCE), an alternative naming of the traditional calendar era primarily used in academic circles *Before Present Before Present (BP) years, or "years before present", is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Becaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1408 (film)
''1408'' is a 2007 American psychological horror film based on Stephen King's 1999 short story of the same name. It is directed by Mikael Håfström and stars John Cusack and Samuel L. Jackson. The film was released in the United States on June 22, 2007. The film follows Mike Enslin, an author who investigates allegedly haunted houses and rents the titular room 1408 at a New York City hotel. Although skeptical of the paranormal, he is soon trapped in the room where he experiences bizarre events. Reviews were mostly positive and the film performed positively at the box office. Plot Mike Enslin is a cynical and skeptical author of niche books debunking supernatural events, in which he has no belief. While promoting his latest book, he receives an anonymous postcard depicting The Dolphin, a hotel on Lexington Avenue in New York City, bearing the message: "Don't enter 1408." Viewing this as a challenge, Mike travels to The Dolphin and requests room 1408. The hotel manager, Gerald Ol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assassination
Assassination is the murder of a prominent or important person, such as a head of state, head of government, politician, world leader, member of a royal family or CEO. The murder of a celebrity, activist, or artist, though they may not have a direct role in matters of the state, may also sometimes be considered an assassination. An assassination may be prompted by political and military motives, or done for financial gain, to avenge a grievance, from a desire to acquire fame or notoriety, or because of a military, security, insurgent or secret police group's command to carry out the assassination. Acts of assassination have been performed since ancient times. A person who carries out an assassination is called an assassin or hitman. Etymology The word ''assassin'' may be derived from '' asasiyyin'' (Arabic: أَسَاسِيِّين, ʾasāsiyyīn) from أَسَاس (ʾasās, "foundation, basis") + ـِيّ (-iyy), meaning "people who are faithful to the founda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arson
Arson is the crime of willfully and deliberately setting fire to or charring property. Although the act of arson typically involves buildings, the term can also refer to the intentional burning of other things, such as motor vehicles, watercraft, or forests. The crime is typically classified as a felony, with instances involving a greater degree of risk to human life or property carrying a stricter penalty. Arson which results in death can be further prosecuted as manslaughter or murder. A common motive for arson is to commit insurance fraud. In such cases, a person destroys their own property by burning it and then lies about the cause in order to collect against their insurance policy. A person who commits arson is referred to as an arsonist, or a serial arsonist if arson has been committed several times. Arsonists normally use an accelerant (such as gasoline or kerosene) to ignite, propel and directionalize fires, and the detection and identification of ignitable liqui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
