It has been said for years that a picture is worth a thousand words. If this is true, the on scene report should paint a picture for all units responding to the incident without using a thousand words.
It has been said for years that a picture is worth a thousand words. If this is true, the on scene report should paint a picture for all units responding to the incident without using a thousand words. How is this done? With as graphic an on scene report as is possible.
There are three areas that need to be covered by the first unit on location to obtain this graphic picture, specifically:
- What have I got
- What am I doing
- What do I need
What Have I Got?
Let's examine the first of these three questions. What Have I Got? Here we want to look at several items that concern all members responding to the incident. Therefore, it is important that the first-in unit reports the following observations.
- Type of construction
- Type of occupancy
- Unusual conditions/hazards
- Location and extent of the fire
- Exposure hazards
- Water supply
Knowing the construction type of the building is very important in determining some factors about the structure. First, the degree of compartmentation within the building could give an idea of the type of floor space involved. It could be a room and content fire found in an apartment style building or a large open area found in a core constructed high rise. We could also come to some conclusion as to the fire load present and the degree of fire spread possible. Other related construction features that pose problems for the firefighters are flat roof buildings with cocklofts, unsealed pipe chases, and balloon construction.
The main concern to any buildings construction is its ability to withstand collapse. The materials used in the construction of the building will help give an understanding of its resistance to gravity. I will use the NFPA Inspection Manual (seventh edition) for classifying the construction types.
Type I: Fire Resistive. This type of construction contains structural members that are of non-combustible or limited combustion material and have a high fire-resistance rating, generally 2 to 4 hours. In most cases only the combustible products and furnishings within these buildings burn posing danger to the occupant and firefighters. The buildings are very sound under fire condition and can withstand a great deal of punishment by fire.
Type II: Noncombustible.This type construction material does not meet the requirements of Type I construction. Generally the materials are metal-framed, metal-clad buildings and concrete-block buildings with metal deck roofs supported by unprotected open-web steel joists. Firefighters should be very cautious in this type structure if any sizable fire involvement exists. These buildings are the least stable in terms of collapse during heavy fires.
Type III: Ordinary. This type construction consists of exterior construction being of noncombustible or limited combustion materials, such as brick, concrete, or reinforced concrete. The floors, roofs, and interior framing are made entirely or partly of wood but in smaller dimensions than are required for heavy timber construction. This type construction is widely used for mercantile buildings, schools, churches, motels, and apartment houses.
Type IV. Heavy Timber. This style building is fabricated using columns, beams, and girders. And roof deck planks that must have specific minimum dimensions. The exterior walls are normally masonry. Contrary to the heavy fire loads within these structures, they hold up well in terms of fire resistance.
Type V: Wood Frame. With this type construction the exterior walls are principally or entirely made of wood or some other combustible materials and it does not qualify as Type III or Type IV. Sometimes this type of construction is referred to as "frame" construction. Interior walls and partitions are framed with 2-by-4 inch wood studs attached to wood sill plates. The main concern to firefighters in this type construction is the void spaces through which toxic gases and fire can travel undetected.