BASEMENT FIRES

BASEMENT FIRES

BY BOB PRESSLER



Photos 1, 2. As you arrive at this late-afternoon fire, the first engine company and ladder company have already started their initial attack. The fire building is an older ordinary brick and wood joist structure with a full basement, a commercial occupancy on the first floor, and living areas above. The fire originated in the basement and the proprietor has informed the first companies that everyone is out of his store. Exposures 1 and 4 are streets. Exposure 2 is a similar attached building, and exposure 3 is a one-story setback attached to the main fire building.

The first line is in operation, and a heavy smoke condition covers the area. As the incoming chief officer, what strategies would you employ to try to stop this fire, and what building features will hinder your operation?

Let`s take a look at this building, floor by floor, and see what building characteristics will help our attack and which ones will hinder our operations. Basement fires in these older attached buildings offer some unusual challenges. Heavy fire loading and restricted access make it difficult to get that important first line into operation (photo 3). Because most small stores have limited storage area on the first floor, the basements becomes the storage area for almost anything. Paper goods, unused appliances, and even furniture may be found in this belowgrade area. To compound the problem, stock is piled to the ceiling, with narrow aisle space between rows.

Ventilation openings are few, and those that are present are small. Companies operating on the basement stairs or in the basement will be subjected to high heat and heavy smoke conditions. The engine company should stretch the first line to the interior of the store to ensure that all people are out of the building and to protect the interior staircase, if present. If the interior staircase is left unprotected, the fire may be pushed up this staircase as the engine moves in on the basement fire. If the fire condition in the basement is light, the handline may be able to advance down the stairs and extinguish the fire. But most times, the fire conditions will be too severe, and this company will be forced to remain on the first floor, protecting the stairway.

The second handline stretched should go to the exterior entrance to the basement, if there is one, and try to advance down these stairs to the basement. Most times this is the line that will actually get to put out most of the fire.

Handline selection is also important for fires in these occupancies. Although building size may not suggest that a large-caliber handline be stretched, most other factors will dictate this. The increased reach of the stream, larger volume, and greater penetration associated with the larger handline will all be needed to reach the base of the fire.

Other problems are associated with basement fires such as this one. In many cases, the basement ceiling will be unfinished, meaning that the fire is immediately attacking the floorboards of the first floor. This leads to early burn-through and floor collapse. The stairs that lead to the basement from the interior should also be suspect. They are normally just steps, with no risers, and the fire will also cause their rapid failure. If the forces cannot enter the basement from the interior, the companies on the first floor must be aware of the fire`s progress. The first floor may become untenable and the floor unsafe to operate on. Streams can be directed into the basement in areas where the fire has burned through the floorboards, but not if other companies are trying to push in to the basement from the exterior. One other option is to use cellar pipes or distributors. They work very well for basement fires that keep companies from advancing into the fire area, but exercise caution, as all companies will be working from a position above the fire.

Another building feature of concern to the incident commander at these basement fires is the area where the floor beams of the first floor are anchored into the party wall between the two buildings. Many times fire has spread from one basement to adjoining property because the beams shared the same cavity or pocket in the party wall or the wall was breached for other reasons.

FIRST-FLOOR FIRES

Photo 4. The fire has now spread from the basement to the first floor and has caused a section of the floor inside the front door to collapse into the basement. Companies are having a hard time getting water to the seat of the fire. Smoke is showing from both abovegrade floors of the original fire building. Suddenly, the store in the adjacent building has smoke pushing under pressure from around the windows. The windows start to self-vent, and heavy superheated smoke starts to boil out of the storefront. The fire has spread to the exposure!

As the fire burns unchecked in the basement, it will also start to burn upward and outward. The fire will follow any open channels, either horizontally or vertically, as far as possible. Open the first and second floors to check for fire extension. This can be done as the truck companies conduct their primary search for life. Open interior walls in the kitchens and bathrooms in the upper-floor apartments. Always suspect these two locations for vertical fire travel, as this void is open from the basement to the top floor and often right through the roof. As the companies perform their searches, they should be venting the windows in these occupancies. Basement fires produce great quantities of smoke, most of which is spreading throughout the building because of the limited avenues of travel to the exterior. Conditions on the inside will be extremely poor. The only chance for success in stopping this fire will be to provide adequate ventilation. As the fire spreads upward, remove the windows of the store and the windows on the upper floor. It serves no purpose to save the glass and burn down the building. Since it is a flat-roof building, vertical ventilation at the roof level is required. Remove scuttles, skylights, and other natural openings as soon as possible to help alleviate the smoke condition in the building on all floors.

The first-floor level also brings another entrance to the fire store into play. The setback provides another position from which to operate. You can stretch an additional handline to this position either to help attack the basement fire or, if the handline from the front cannot move in due to the collapsed floor, to assist in controlling the first-floor extension.

THE SECOND FLOOR

Photo 5. As the fire continues to spread upward, firefighting strategies need to be adjusted. The second-floor apartments need to be searched for any overcome occupants. The spreading fire must be exposed from its hidden voids. This is best accomplished under the protection of a handline stretched to the upper floor via the main staircase. Stretching the handline up the stairway protects the main means of egress for operating forces and trapped civilians.

In addition to the horizontal ventilation being performed, as the fire spreads upward, increased vertical ventilation becomes a necessity. After performing their initial roof operations of opening scuttles and skylights, the firefighters assigned to the roof position should now determine in which location it would be the most advantageous to perform additional roof ventilation. As part of their initial size-up, they also should have checked to see if a light and air shaft are between the two buildings. Older structures such as these frequently have a shaft, either diamond- or rectangular-shaped, between the buildings. Fire that enters these shafts will rapidly spread from one building to the other. If a shaft exists between the buildings, notify the IC immediately.

If the fire is spreading upward through hidden voids, the roof team may have a difficult time trying to determine the best place for a ventilation opening. When dealing with a rapidly spreading basement fire, especially in a smaller building such as this, holes can be cut in the front and rear sections of the roof. If possible, cut the holes in the area of the soil pipes. Because the fire has been burning unchecked now for some time, cut the largest possible holes, and monitor the holes for increased smoke or heat production.

Interior companies must still try to open up all hidden voids. They must open the walls and pull the ceilings on the first and second floors to expose any hidden fire. This is especially true on the second floor, where the fire may be entering the cockloft. If the fire enters the cockloft area, it will spread unchecked over the entire building area and possibly into the adjoining building. Personnel operating on the roof will have to monitor conditions and keep the IC informed.

As with all fires, sometimes the best intentions go unrewarded: The fire has spread throughout the cockloft of the fire building and also into the adjoining building. The IC must know when the fight is lost. If all possible areas that could have been reached have been searched for trapped civilians and the fire has spread beyond the capabilities of the chief or his forces, abandon the fire building. Protect exposures, and take operating personnel out of the collapse zone. n




Photos 4 and 5 by author.

BOB PRESSLER, a 22-year veteran of the fire service, recently retired as a lieutenant with the City of New York (NY) Fire Department. He created and produced the videos Peaked-Roof Ventilation and SCBA Safety and Emergency Procedures for the Fire Engineering video series “Bread and Butter” Operations. Pressler has an associate`s degree in fire protection engineering from Oklahoma State University, is a frequent instructor on a wide range of fire service topics, and is a member of a volunteer department.

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