Fire protection
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Fire protection is the prevention and reduction of the hazards associated with 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 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.
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[edit] Goals
Fire protection has three major goals:
- Life safety (minimum standard in fire and building codes)
- Property protection (typically an insurance requirement, or a regulatory requirement where the protection of building components is necessary to enable life safety)
- Continuity of operations (typically an insurance requirement or an item of self-motivation for building owners - not a regulatory issue). Interruption of operations due to fire damage can be very costly. For instance, a nuclear reactor may cost about one million US dollars per day, if it is not making power that is being sold.
[edit] Components
Structural fire protection (in land-based buildings, offshore construction or 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 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 protection and Passive fire protection, its weak spots and strengths to ensure the highest possible level of safety)
[edit] Balanced Approach
Passive fire protection (PFP) in the form of compartmentalization was developed prior to the widespread use of active fire protection (AFP), mainly in the form of fire sprinklers. During this time, PFP was the dominate mode of protection provided in facilities designs. With the widespread installation of fire sprinklers in the past 50 years, the reliance on PFP as the only approach was reduced. 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.
Lobby groups are typically divided into two camps favoring active or passive fire protection. Each camp tries to garner more business for themselves through their influence in establishing or changing national fire codes. At present, the camp favoring AFP appears to be favored.
A balanced approach between all three parts, Education, AFP and PFP, is generally recognized 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 experienced engineers 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 tends to support AFP initiatives, and can lead to the justification for less substantial construction. Some proponents of PFP feel 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 solid structures. At times it works the other way around, as firewalls that protrude through the roof structure are used to "sub-divide" buildings such that the separated parts do not require sprinklers.
The decision to favor 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 significant 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.
[edit] Common items to check for to avoid systemic problems
If any one of the three components of Fire Protection fail, the fire safety plan can be immediately and severely compromised. For example, if the firestop systems in a structure were inoperable, a significant part of the fire safety plan would not work in the event of a fire. Since the overall plan depends on all pieces, it is important to see that each item is in fact functional. Likewise, if there were a sprinkler system or an alarm system, but it's down for lack of knowledgeable maintenance, or if building occupants prop open a fire door and then run a carpet through, the likelihood of damage and casualties is markedly increased. It is vital for everyone to realise that fire protection within a structure is a system that relies on all of its components.
There are many things that can and often do go wrong prior to and during the construction of a building. What happens afterwards, however, can also be substantially hazardous, to the point of entirely defeating the fire protection plan that was put in place during the design-phase of a building. Common operator errors include, but are not limited to, the following: failure to regularly clean grease ducts in commercial kitchens (usually every 3 - 6 months), re-entering firestops without proper repairs, damaging and removing spray fireproofing [1] from structural steel elements, changing of the use or occupancy [2] of parts of a building. Any changes that affect the overall fire protection plan, however small they may appear to the layman, legally require the owner to either gain the approval of the fire prevention officer at the municipal fire department or to apply for a building permit with the local, municipal building department. The permit fee is intended to cover the time and expenses for the Authority Having Jurisdiction to evaluate the contemplated change against applicable code requirements. Failure to obtain such approvals make the owner vulnerable to charges of negligence and culpability in a court of law.
[edit] Questions for inspectors
These two questions can be used as a litmus test for a building, offshore construction or ship owner's degree of due diligence:
- "How many firestops are there in your building/ship, where are they and where do you keep copies of the certification listings that cover each opening?"
- "Where is your local copy of the current fire code and the construction code(s) that were in effect when you applied for the permit(s)."
The correct responses are the precise number of firestops and a reference to a set of drawings that shows each one with a number and hyperlink or paper reference to the certification listings and the location of the two documents.
The former question tests the owner's knowledge of his or her structure's fire protection and continued compliance with the code by bringing up the example of a common deficiency: the firestopping of existing and new openings in wall and/or floor assemblies required to have a fire-resistance rating. Answers to the latter question expose an owner's ability to keep the fire protection system set up correctly under normal operations and remedial work. The documents are necessary as nobody (including members of an Authority Having Jurisdiction), can be expected to know an entire code by heart. Both fire codes and building codes will refer to one another (to avoid duplication of text).
Examples for remedial work are plumbing work (a new toilet for instance, which could cause the need for a dozen new firestops to be made and breaches of fire barriers), electrical work (say a new recepticle in a wall, which necessitates a conduit and cable), new doors, changing the use of a room, etc.
These materials need to be known by the operators and staff of the building as any routine, seemingly small act, can defeat the overall fire protection plan, which forms the design basis for the building. For example, the installation of some piece of equipment in the building such as a water pump. Depending on where this is installed, it could be construed as a change in occupancy, which in turn requires a building permit to ensure compliance with regulations. Likewise, added piping or cable to run the equipment might necessitate the breaching of a fire-resistance rated wall or floor, where now a firestop is required, which would also necessitate a building permit. If no application for a building permit is made, the Authority Having Jurisdiction is unaware of the change and if the change is not immediately apparent to a fire prevention officer, nobody is the wiser but the owner is culpable.
It is important to remember that even when a fire prevention officer who conducts an inspection does not find anything amiss, this does not mean that the building is in full compliance with the fire code. There is a limit to the amount of searching and disturbing that a fire prevention officer is legally allowed, financed by the municipality, and able to do. For instance, an inspector may only be given one hour to inspect a school, which would not be enough time for an in-depth check. An inspector may be limited to a quick check on fire extinguishers and maintenance records of the sprinkler system. The written OK given after an inspection is only an "OK" for the parts inspected, which may not include things overlooked which severely breach the code. A passed inspection does not absolve a building owner of his or her responsibility to maintain the entire facility in compliance with the fire code, nor does it give them carte blanche that everything is OK with the Authority Having Jurisdiction.
[edit] See also
- Gas Based Systems
- Clean agents
[edit] External links
- Performance/Objective Based Codes
- National Fire Protection Association
- ULC
- DIBt
- detailled DESCRIPTION of different fire extinguishing systems
- (http://www.hkc22.com/fireprotection.html) The Future of the Fire Protection Markets Worldwide 2005 to 2010 and 2015
