- Fire protection
Fire protection is the study and practice of mitigating the unwanted effects of
fires [NFPA Fire Protection Handbook, pg. 2-19] . It involves the study of the behaviour, compartmentalisation, suppression and investigation of fireand 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 codeand 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 constructionwith the building code. Once constructionis complete, a building must be maintained in accordance with the current fire code, which is enforced by the fire prevention officers of a local fire department. In the event of fire emergencies, Firefighters, fire investigators, and other fire prevention personnel called to mitigate, investigate and learn from the damage of a fire. Lessons learned from fires are applied to the authoring of both building codes and fire codes.
In the United States, this term is used by
engineers and code officials when referring only to active and passive fire protection systems, and does usually not encompass fire detectionsystems such as fire alarms or smoke detection.
Fire protection has three major goals:
*Life safety - the minimum standard used in fire and building codes.
*Property protection - on a public scale, this is intended to prevent area wide conflagrations. At an individual building level, this is typically an
insuranceconsideration (e.g., a requirement for financing), or a regulatory requirement.
*Continuity of operations - on a public scale, this is intended to prevent the interruption of critical services necessary for the public welfare (e.g., a 911 emergency call center). To a private owner, this is typically not a regulatory issue, but is self-motivated, sometimes partially due to fire
insuranceconsiderations. Interruption of operations due to firedamage can be very costly. For instance, the lost revenue to a power company if a nuclear reactor is shut down due to a fire may cost about one million US dollars per day.
When deciding on what fire protection is appropriate for any given situation, it is important to assess the types of fire hazard that may be faced.
Some jurisdictions operate systems of classifying fires using code letters. Whilst these may agree on some classifications, they also vary. Below is a table showing the standard operated in Europe and Australasia against the system used in the United States.
Fires are sometimes categorized as "one alarm", "two alarm", "three alarm" (or higher) fires. There is no standard definition for what this means quantifiably, though it always refers to the level response by the local authorities. In some cities, the numeric rating refers to the number of fire stations that have been summoned to the fire. In others, the number counts the number of "dispatches" for additional personnel and equipment. [http://www.nbc4.com/money/9208480/detail.html] [http://www.thevillager.com/villager_39/fouralarmfire.html]
Structural fire protection (in land-based
buildings, offshore constructionor onboard ships) is typically achieved via three means:
Passive fire protection(use of integral, fire-resistance rated wall and floor assemblies that are used to form fire compartments intended to limit the spread of fire, or occupancy separations, or firewalls, to keep fires, high temperatures and flue gases within the fire compartment of origin, thus enabling firefighting and evacuation)
Active fire protection(manual and automatic detection and suppression of fires, as in using and installing a Fire Sprinklersystem or finding the fire ( Fire alarm) and/or extinguishing it)
Education(ensuring that building owners and operators have copies and a working understanding of the applicable building and fire codes, having a purpose-designed fire safety plan and ensuring that building occupants, operators and emergency personnel know the building, its means of Active fire protectionand Passive fire protection, its weak spots and strengths to ensure the highest possible level of safety)
Passive fire protection (PFP) in the form of compartmentalisation was developed prior to the invention of or widespread use of active fire protection (AFP), mainly in the form of automatic fire sprinkler systems. During this time, PFP was the dominant mode of protection provided in facility designs. With the widespread installation of fire sprinklers in the past 50 years, the reliance on PFP as the only approach was reduced. The result has been a signifiant per capita reduction in the loss of life and property form unwanted fire.There is a perception by some fire protection engineers and some members of the fire protection construction industry that the model building codes have changed with too much reliance on AFP. However most persons recognize that the best solution to an unwanted fire is to put it out as soon as possible... thus the increasing use of fire sprinkler systems.
Lobby groups are typically divided into two camps favouring active or
passive fire protection. Each camp tries to garner more business for itself through its influence in establishing or changing local and national building and fire codes. At present, the camp favouring AFP appears to be leading, because of the factors mentioned above.
A balanced approach between all three parts,
Education, AFP and PFP, is generally recognised to be the best overall approach, but there are disagreements in emphasis. This is to be expected, considering that many of the proponents of one camp or another have a vested interest in the outcome, as they are involved in the sales or construction of one of the systems. Many insiders in the trade, who know how much field conditions can influence matters, conclude that no one side has all the answers.
The relatively recent inclusion of "performance based" or "objective based" codes tend to support AFP initiatives, and can lead to the justification for a lesser degree of fire resistant rated construction. Some proponents of PFP feel that this new approach is not properly balanced, as the use of automatic suppression with codes allowing "performance based" designs often favours the cost savings resulting from less fire resistant structures. At times it works the other way around, as firewalls that protrude through the
roofstructure are used to "sub-divide" buildings such that the separated parts are of smaller area, therefor contain less fire hazards, and thus do not require sprinklers.
The decision to favour AFP versus PFP in the design of a new building may be affected by the lifecycle costs. Lifecycle costs can be shifted from capital to operational budgets and vice versa. AFP, may initially require less capital to install, but due to its nature requires on-going operational resources to maintain. PFP on the other hand, may be more costly to install but less costly to maintain. Planners consider the expected life expectancy of a building to make the most beneficial long term decision.
Building Operation in conformance with Design
The building is designed in compliance with the local
building codeand fire codeby the architect and other consultants. A building permit is issued after review by the Authority Having Jurisdiction (AHJ).
Deviations from that original plan should be made known to the AHJ to make sure that the change is still in compliance with the law to prevent any unsafe conditions that may violate the law and put people at risk. For example, if the
firestopsystems in a structure were inoperable, a significant part of the fire safety plan would not work in the event of a fire because the walls and floors that contain the firestops are intended to have a fire-resistance rating, which has been achieved through passing a fire testand, often, product certificationof the components involved in the construction of those walls and floors. Likewise, if the sprinkler system or fire alarm system is is inoperable for lack of knowledgeable maintenance, or if the buildingoccupants prop open a fire doorand then run a carpetthrough, the likelihood of damage and casualties is increased. It is vital for everyone to realise that fire protection within a structure is a systemthat relies on all of its components.
Authority Having Jurisdiction
Listing and approval use and compliance
Passive fire protection
Active fire protection
Fire alarm system
Fire alarm control panel
Manual call point
Gaseous fire suppression
Fire protection engineering
* [http://www.fireengineering.com/articles/article_display.html?id=196217 "Fire Engineering" Article by Richard R. Licht entitled CLARIFYING THE ISSUE OF FIRE PROTECTION BALANCE]
* [http://afscc.org/ Alliance for Fire and Smoke Containment and Control]
* [http://jfe.sagepub.com/ Journal of Fire Protection Engineering]
* [http://www.nfpa.org/ National Fire Protection Association]
* [http://www.ulc.ca/ ULC]
* [http://www.dibt.de DIBt]
* [http://www.nfsa.org National Fire Sprinkler Association]
* [http://afscc.org/Papers/0507Trawtestimony.pdf BALANCED FIRE PROTECTION statement by Jon S. Traw]
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