Co. Officer Ch. 10 Flashcards
Today’s firefighting requires experience, knowledge, and skills:
Modern firefighting requires more than just experience; it requires knowledge and skill. With the gradual decline in number of serious fires encountered, good officers will learn from every opportunity, including actual working incidents, participating in training and drills, attending seminars, and reading about the subject as much as possible.
As a new officer, riding on an engine or truck company arriving at the scene of a working fire or other emergency:
A new officer may be overwhelmed. Due to lack of experience and for training.
– At the scene of emergencies, the first arriving officers are usually concerned with limited resources, time and many unknown factors. Working in these conditions is difficult and dangerous; leading others under such conditions can be extremely challenging.
– You are expected to be calm and decisive, to issue clear orders, and to keep track of all the activities. You are responsible for the safety of others. You’re responsible for at least some aspect of the management of the incident and, in many situations, may be the incident commander
Who was the chief of the London fire brigade in the 1870s?
Massy Shaw. He visited the United States and criticized Americas firefighters for their lack of knowledge of the fire protection industry.
Who wrote the classic text fire ground tactics?
Emanuel fried
– He stated that command on the fire ground is a demanding task for the officer. To improve the ability to handle the situations we have to concede certain basic faults we find in ourselves. Admit these possibilities:
– You are going to get excited
– You are going to yell
– You are going to make mistakes
– You were going to lose buildings
– Note: many factors contribute to the company being ready to deal with emergency situations, including your knowledge of the job
Understanding the communities needs:
Fire department should be assessing their communities risk factors. This is the first step in identifying the strengths and weaknesses of the department in dealing with emergencies.
Members of the company responsible for that area should be interested in the risk factors in that area. They should look at specific situations where they may be called upon to save lives and protect property and should also be thinking about the overall community consequences.
For company officers, a general knowledge of your area of responsibility this is essential for effective operations. This knowledge includes the following:
– Physical factors: geographical size, population, valuation, response time, and topography of the community
– Excess factors: excess and barriers to all areas
– Occupancy factors: the nature of the businesses that occupy the buildings
– Structural factors: age, type, and density of the structures
– Resource factors: fire department resources, and for firefighting purpose, water supply capabilities
– Survival factors: stairwells and other penetrations to allow for rescue, fire spread, and potential falling hazards for firefighters
Building construction:
– During the course of your fire service career, virtually every commercial building and all but a few residential buildings you encounter will have been constructed or renovated under a construction code.
– There is an axiom in the construction business: which of the five types of construction is preferred by design professionals for their projects?
The cheapest!
What is the primary purpose of a building code?
– Prescribe standards that will keep buildings from falling down. – Gravity – Snow loads – Wind loads – Potential earthquake loads
What are the goals of building codes?
– Maintain the integrity of the structure and prevent collapse
– Limit fire size by preventing fire spread
– Provide adequate time for occupants to escape or shelter within
– The girls can be met in a variety of ways, using fire resistance rated construction, fire extinguisher and systems, and noncombustible building materials and providing adequate fire separation distance.
Two important terms to understanding construction types are:
Noncombustible and fire resistance.
– A noncombustible building material will not burn, and fire resistance is the resistance of a building to collapse for two total involvement in fire.
The length of time typical structural members and assemblies resist specified temperatures under test conditions?
Tthe late Frank Brannigan described it as fire endurance
How construction types affect you:
In general, it can be said that the building makes the problem.
For the most part, fires that a current building supposed to greatest risk to the occupants and fire fighting forces, and pose the greatest challenge. Branigan made his point by describing a fire involving 50 upholster chairs stacked in a barren field as one unit response using less than a tank of water. The same fire in a Hilton hotel killed two people and injured 36 others. Fire intensity and behavior will, for the most part, be affected by the types of building materials used, the construction methods, and the built in fire protection features installed during construction
Types of construction:
There are three key points to remember when dealing with building construction types:
– All construction is either combustible meaning it will burn, or noncombustible and it won’t
– The term protected, when applied to construction materials, means protected from the effects of fire by encasement. Concrete, chip some spray on coatings are all used to protect construction elements. Protected construction does not mean the building has a sprinkler system
– The code specifies the minimum requirements, but permits the use of materials that extract those requirements. Making assumptions based on your view from the street is risky and potentially hazardous for you and your crew.
– Some buildings with combustible components are actually more fire resistant then some noncombustible buildings. That is where protection structural elements comes into play. A lightweight steel building may be noncombustible but will fail quickly when exposed to a fire involving combustible contents. Conversely, buildings with masonry exterior walls and heavy timber choice of combustible components that hold up quite well compared to lightweight steel.
Determining construction type:
The occupancy classifications, building area, number of stories, location on the lot, distance from the lot lines, fire department access to the exterior of the structure, and whether the building will be equipped with sprinklers all have to be established before the minimum construction type can be determined.
– Occupancy classifications that are more hazardous, based on the vulnerability of the occupants – hospitals and nursing homes – or the relative hazards associated with the function of the building – repair garage versus an office building for the materials handle or stored manufacturing or processing hazardous materials, have more stringent construction requirements
Five construction types:
There are five basic construction types recognized by the international building code or IBC. The IBC's predecessor regional building codes used slightly different terms for the same basic types. – Type one: fire resistive – Type two: noncombustible – Type III: ordinary – Type for: heavy timber – Type five: frame
Type 1: fire resistive construction:
In type one construction, structural elements are noncombustible and our protect to the highest level. Type one is divided into two subtypes. The difference between them is the level of protection for the structural elements – expressed in hours –. Only noncombustible materials are permitted for the structural elements. Structural steel is encased in concrete, gypsum, or cementaceous Coating.
– High-rise buildings with steel structural elements encased in concrete or examples of type one buildings.
Type two: noncombustible construction:
Type two construction, the structural elements are also noncombustible. The difference between type one fire resistive and type two noncombustible is in the level of protection of the structural elements. Type one is protect to the highest level. Take to subdivided into subtypes; one is protected less then type one and the other has no protection. Type two buildings are noncombustible but are afforded limited or no fire resistance for the structural elements
– The typical strip shopping center or big-box store with masonry block walls, steel bar joists, unprotected steel columns, and the steel roof deck is a type to be unprotected building. If there is a sprinkler system failure, the roof structure can fail quickly and collapse
The sofa superstore in Charleston, South Carolina, was originally constructed in the 1960s under the standard building code:
It was originally constructed in the 1960s under the standard building codes equivalent of IBC type IIB construction.
– Automatic sprinklers were not required by the code at that time. The roof structure failed and collapsed 43 minutes from the time the first hand while he was deployed on the fire that started on the exterior loading dock. Steel is a superior building material, with good strength in both tension and compression. However, steel loses almost half of its strength at 900°.
Characteristics of steel structures:
Steel has a high thermal conductivity, which means it can transfer heat away from a localized source and act as a heat sink. If an intense fire is evenly distributed along the steel member, the critical temperature may be reached very quickly. Steel also has a high coefficient of expansion that results in the expansion of steel members as they are heated. A 50 foot long steel beam heated uniformly over its length from 72° – 972°F will expand in length by 3.9 inches
– The same being heated to 800°F would expand by 3.2 inches; if heated to 1200°F to being would expand by 4.9 inches
Type III: ordinary construction:
In type III construction, the exterior of the building is noncombustible, typically masonry, it may be rated depending on the horizontal distance to exposures. The interior structural elements may be of any of the material, combustible or noncombustible.
– Type III construction is divided into two subtypes: protected and unprotected.
– The brick, wood joist did buildings that line our city streets are of type III construction, for ordinary construction. The term ordinary dates back to the time when most city and town building codes established fire districts where combustible building exteriors were prohibited to reduce conflagration potential. It was the least expensive type permitted. Ordinary construction is not very ordinary anymore – it has become too expensive!
Type four: heavy timber construction:
Type IV construction dates back to the new England cotton and wouldn’t mills of the mid-1800s. Mill owners banded together and formed mutual fire insurance companies, but only insured the best risks. Type for heavy timber construction is also called mill construction. The exterior walls are noncombustible masonry, and the interior structural elements are unprotected would of large cross sectional dimensions.
– Columns must be at least 8 inches if supporting a floor load, and Joists and beams must be a minimum of 6 inches in width and 10 inches in depth. Type four is not subdivided. The inherent fire resistive nature of large diameter would members is taken into account. A key strength is that concealed spaces are not permitted within the structure
Type five: Frame construction:
In type V construction, The entire structure may be constructed of wood for any other approved material. Type V was called woodframe in the past, because Woodcliff usually the least expensive material for the job. The high cost of lumber has led to an increase in lightweight combustible composites, and to the use of lightweight steel for studs. How well wood structural members will resist the effects of fire is directly related to their mass.
Hash the 6X 10 – inch floor joists type for building can be expected to support the floor for sometime when exposed to a fire. Light waitresses may fail in minutes.
– Type the construction is subdivided into protected and on protected types, again depending on the protection provided for the structural elements.
Performance codes:
Firewalls, fire barriers, and fire partitions are all designed to resist the spread of fire, but they are not the same thing. Firewalls are structurally independent and separate buildings. For your barriers and fire partitions are constructed within a building and separate fire areas, or block the passage of heat and smoke from corridors or other areas.
– Modern building codes are for the most part performance coach. Rather than specify the exact construction of a components such as a firewall, the codes identify a performance feature. Where is the specification code might require all firewalls to be of a certain thickness of masonry block, a performance merely code identifies the performance required, such as resisting the passage of heat and some for a given time.
Performance –based design:
Performance-based design is an alternative method for satisfying the fire protection and life safety intent of construction codes. The ICC performance code for buildings and facilities finds performance-based design as:
– And engineering approach to design elements of a building based on agreed upon performance goals and objectives, engineering analysis, and quantitative assessment of alternatives against the design goals and objectives are using excepted engineering tools, methodologies, and performance criteria
The international forum of fire research directors issued a position paper on performance based design for firecode applications.
In March 2007, research directors issued a position paper on performance-based design for firecode applications. This title is slightly confusing. The paper address is performance-based to sign for safety aspects of building codes. The committee noted the limited potential use for performance based design:
– For the majority of traditional buildings with flow has heard occupancies, modern prescriptive building, and fire codes, when enforced, achieve this objective. Nontraditional buildings including many of societies largest and iconic structures, such as opera houses, museums, sports stadiums, transportation centers, super high right structures, and some government buildings.
Prescriptive codes:
Prescriptive codes do not adapt rapidly to changing materials and methods of construction, nor too radical architectural designs; and prescriptive code based upon historical lost experiences are not designed to deal with very low probability, very high impact events for other threats such as from terrorism
