FIRE LOSS MANAGEMENT
FIRE PHIEM
SFPE
Part 12: EXTENSION— FLAME SPREAD, CONTINUED
The potential for disastrous flame spread is not always obvious. A broad knowledge of flame spread and a vivid imagination are sometimes necessary.
CONSTRUCTION IN OCCUPIED BUILDINGS
There is available a bituminouscoated, hemp-impregnated Kraft paper for the protection of easily damaged shipments, such as highly finished laminated beams. It is often used for purposes for which it was not intended. This material has a tremendously high flame spread, and because of the combination of bituminous and paper, is a serious fuel contribution and smoke generation hazard.
In 1951 the Atomic Energy Commission was constructing an addition to Strong Memorial, a five-story general hospital in Rochester, New York. The addition was built on the rear of the hospital at right angles to a wall in which there were scores of windows and patients’ rooms. Because the excavations were scheduled for the wintertime, a snow roof was needed — cheap material to give some waterproofing characteristics to the roof. Kraft paper was purchased and used.
In the corner of the construction area there was a room in which employees changed into their work clothes. This was heated by a potbellied stove fed by scrap wood. When I arrived on the scene, the stove was burning and sparks were pouring out of the stack.
I tore off a section of the Kraft paper and ignited it in the presence of the on-site engineer. It blazed up instantly. It took him about two seconds to realize the implications of a sheet of fire racing up the face of an occupied hospital, and necessary corrective measures were taken.
A major alteration was underway adjacent to the infant nurseries in a large, unsprinklered university hospital. A plywood wall was erected, and the construction work proceeded in the usual fashion with all the attendant hazards. No doubt the building department approved the plans for the finished building, and the fire inspector probably checked that there were fire extinguishers, but nobody looked at the total hazard picture.
The fire department should be alerted as soon as plans are filed for any construction work in heavily populated buildings. A conference should be held with the building department, the owner, and the architect before the job goes out for bids. Special fire precautions cost money. However, point out to the owner and architect their inescapable serious liability exposure both in dollars and possible criminal action if a disaster occurs.
The plywood wall was temporary, but this does not excuse unsafe practices. There may be some occasions when a temporary lapse of good practice may be permitted, particularly if some substitute can be provided. However, in no case should we permit a temporary situation to create massive hazards and be accepted on the grounds that it is temporary—it may be all too temporary.
FLOORS
A radiation facility suffered a serious contamination incident. As the area was being cleaned up it was necessary to “paper it down” to prevent backtracking contamination. The same reinforced paper was purchased and used. The hazard was evaluated only when pictures of the operation arrived in AEC Headquarters. Here again, the tremendously rapid flame spread, fuel generation, and smoke contribution would certainly have caused a redistribution of the contamination and probably a serious loss to the equipment. There isn’t much point in protecting material from radioactive contamination and then destroying it by fire.
In another example, highly finished laminated timber arch sections were stored adjacent to weeds and grass at a construction site. A minor grass fire extended to the paper and heavily damaged the laminated timber.
When highly polished wooden floors such as those in bowling alleys and gymnasiums are being refinished, they represent a tremendous flashftre hazard. The sealers and finishers that are used often contain highly flammable material such as nitrocellulose. The refinishing of a bowling alley or the provision of a “bowling alley finish” to a wooden floor is an operation that requires the most drastic control. The building should be closed, the electrical service should he disconnected, adequate ventilation must be provided, and fire hoselines should be laid out and charged in order to be ready. The entire operation should be kept under surveillance from beginning to end. There is probably no more dangerous single operation in a building than refinishing large areas of wooden floors.
(Photos by author.)
Some floor waxes are highly flammable, particularly those used on wooden floors. Fortunately, the waxes for composition tile floors cannot contain solvents, as this would destroy the tile. Floor waxes used for wood have been known to ignite when being buffed by electric buffers. In one case this caused the deaths of several patients in traction splints.
In the construction and repair of buildings, mastic cements are used to set floor tiles. Many of these cements contain highly flammable solvents. Fatalities have resulted front the ignition of this cement during construction work. The construction or repair of tile floors demands an analysis of the hazard involved.
CARPETING
Burning carpeting can fill a corridor with flame. It would be a mistake to hit the fire with fog, as this would drive the fire along the surface of the carpet. Use a solid stream instead. Get the water through the fire to wet the carpet beyond. This temporarily “fireproofs” the carpet and the fire is cut off.
In 1981, fire extended up the face of the Las Vegas Hilton, fed by combustible carpeting used for ceiling decoration in elevator lobbies. Eight lives were lost.
Carpeting is tested in two ways. One way is FF 1 -70, also known as the “pill test.” The “pill test” only measures the ignitability of the carpet from small flame sources such as a dropped, burning match. It does not measure the carpeting’s contribution to the fire.
If the carpet may have contributed significantly to the fire and it passes the “pill test,” it may be useful to test its flame spread properties using unburned samples. One such test procedure is that given in NFPA 253, Standard Method of Test for Critical Radiant Flux of Floor Covering Systems Using a Radiant Heat Energy Source. For this test, samples 10 x 42 inches are required. If a pad was used with the carpet, it should be included with the carpet in the test. This standard measures the radiant energy required to keep the carpet burning. The lower the energy value, the higher the flame spread. It also is used in NFPA 101, The Life Safety Code 6-54 Interior Floor Finish Classification.
The standard leaves it up to local authorities or the owner to make a carpeting decision based on the values given. One problem lies in the manufacture. Recently a carpet manufacturer was taken over by another. It was discovered that the management had falsified test results on millions of square feet of carpeting, which already had been shipped and installed.
CEILINGS AND WALLS
Laminated wooden arches and heavy wooden planking are used for the roofs of many types of buildings. The exposed finished underside of the planks is the ceiling. A church was set on fire in a lightweight, combustible choir robing room. When the fire burst out of the room, it was heavily advanced and spread over the entire surface of the church, charring the wood. The slate roof was practically undamaged. Structurally the building was sound and the arches lost none of their necessary structural strength, but as for its appearance, the church was destroyed.
A similar fire in a Florida church was attacked vigorously with heavycaliber, solid streams. (Solid streams penetrate the body of flame and wet the surface, where the fire originates—fog is eaten up by the flame.) The beams were charred only slightly and were sandblasted successfully.
The appropriate fire loss solution is to eliminate or protect by sprinklers small combustible structures such as a robing room or sacristy inside and out. If this is done, there is little chance of the fire being vigorous enough to extend to the ceiling.
Combustible ceiling materials are often used for wall treatments, and lightweight plywood veneers are commonly used for decorative walls. When spaced out from the wall on furring strips, they provide fire paths both behind and on the surface, thus more than doubling the fire hazard.
Restaurants, dining rooms, and executive offices are often paneled in heavy wood. This paneling can burn on the rear side, impervious to fire streams. Such a fire requires large handlines to combat the intense heat generated.
In one case, fire involved this heavy wood paneling in a high-rise restaurant in a southern city. The fire department, using only 1’/2-inch lines, could not get to three trapped women. Ultimately, they jumped.
FIRE GROWTH IN CONTENTS
For many years the Christmas tree was the prime example of rapid fire growth in contents, but times have changed. Fire roaring out the 12th floor windows during the First Interstate Bank fire in Los Angeles in May 1988 forever laid to rest the fallacy that office buildings have low fire loads. The Center for Fire Research at the National Institute of Standards and Technology in Gaithersburg, Maryland developed a computer model of this fire. This study should be presented to building managers and political officials when there is resistance to retrofitting sprinklers in existing office buildings on the grounds that the fire service is unnecessarily concerned.
A pile of plastic furniture was stored temporarily in a public area of the Du Pont Plaza Hotel in San Juan, Puerto Rico. In 1987, disgruntled employees set fire to it, no doubt to create a fuss and embarrass the management. The fire grew to enormous size almost instantly. A total of 97 lives were lost.
Hotels are remodeled regularly. Mattresses and furniture are removed from rooms and stored in hallways, a tempting target for arsonists. Carpeting piled in the hallway was ignited in a Ft. Worth, Texas Ramada Inn in 1983, and five people died.
Sometimes a hotel floor is taken out of service and used to store incoming furniture, creating a sort of furniture warehouse within the hotel. A fire department only prepared to use the typical high-rise pack will find its attack water hopelessly inadequate. Any indication that a hotel is to be “refurbished,” “remodeled,” or “spruced up” should be a red flag to the suppression forces to determine what changes in fire department tactics are necessary and what additional precautions are required of the management.
Across the nation little has been done to control the hazard of furnishings in buildings. The state of California has done much, as has the city of Boston. For its own considerable holdings, the Port Authority of New York and New Jersey has set requirements. This action was sparked by a devastating fire in a terminal at Kennedy Airport, which was fueled by plastic seats. The New York state requirements recently developed are concerned with toxicity, however, not flammability.
PREPLANNING
The first and most important step in preplanning is education of personnel in the nature of fire growth and the development of their ability to observe and understand the fire growth phenomenon. All should see the NFPA tape/films Fire, Countdown to Disaster, and Fire Power. In addition, knowledgeable personnel should lecture on the subject using Chapter 9 of Building Construction for the Fire Service, 2nd edition; NFPA Handbook, Chapter 7; and the stories of the fires cited here. For fire suppression personnel, the emphasis should be less on codes and more on examples of local fire growth situations.
Tactics should be reviewed. For instance, some fire departments customarily use the service or freight elevator to approach the fire floor. In many cases, the rubbish is consolidated in the service elevator lobby on each floor in preparation for removal. There may be a raging fire right at the elevator, which may affect the controls.
I recommend that each piece of apparatus carry at least one length of 2’/2-inch hose packed for transport so that if heavier streams are necessary on a high-rise fire, the hose will be available. Locations of possible high flame spread areas should be noted on preplans. Drill evolutions should include placing master streams in operation inside buildings and on upper floors. Renovation jobs should be inspected to determine if combustible tile is being left in place above the new ceiling. In general, the consciousness of fire suppression forces on the subject of fire growth should be greatly raised above its present level.*
