THE BUILDING DEPARTMENT SAID THE WALLS WERE OK, BUT…
BY FRANCIS L. (FRANK) BRANNIGAN
The IC, Assistant Chief Harry Norum of the City of New York (NY) Fire Department (FDNY), however, did not trust the walls, built with sand-lime mortar 126 years ago. The building had retrofitted bracing “stars” to the exterior, indicating walls that were tied to floors because of their instability, and they had been battered by tower ladder streams. He maintained the collapse zone. The walls did collapse. No one was injured.
The following is quoted from “Sixth on Sixth” by Joseph Nardone, FDNY battalion chief, concerning the above collapse:1
At approximately 1800 hours, inspectors from the Department of Buildings made an initial assessment of the building. Viewing the exterior of the building, they observed that there were no cracks or bulges in the wall, the walls were not out of plumb, the window openings appeared straight, and the surveyor`s transit (operated by Tactical Support Unit #1) detected no motion. The building was declared stable at this time.
This account of the Building Department`s assessment is not mentioned as criticism but is given here to convey to the reader how the conditions causing the total collapse can be hidden from the most experienced inspector. Even firefighters may be unaware of the deadly swiftness with which collapses occur. Structural wooden members, plaster and stock all absorb water. Mortar loses its adhesive qualities, wood shrinks and rots and steel rusts. It can be difficult for those not in the fire service–such as inspectors from other agencies–to fully comprehend the destructive impact that large-caliber streams have on a building`s structural members. As an extra precaution, the collapse zone was expanded on all sides, despite the outward appearance of the building`s stability.
At 2105, the fire building and exposure 4 suddenly collapsed into a pile of rubble. Twenty-seven minutes later, exposure 2 collapsed suddenly, again without any presignal.
Because of the enforcement of the collapse zone, firefighters were not caught in the first collapse or in the second one while searching for victims of the first collapse.
On the surface, it might seem that the building inspectors were not too swift, but the circumstances are far more complex. The inspectors have never been educated as we have been or should have been about the specific factors that make masonry walls hazardous in a fire [see Building Construction for the Fire Service, Third Edition (BCFS3), pages 153-184].
“Without warning” is a common phrase in collapse reports. The report`s author is referring to immediate warnings such as strange noises, cracks in the wall, water coming through the walls, and other signals learned through bitter experience. Often those with the best “experience” do not live to use it.
The warnings we must heed are such things as the presence of stars on the wall, indicating bracing, as was noted in this case; the age of the building, indicated by the sand-lime mortar; and the fact that many masonry walls were not totally masonry. The practice of using wooden lintels over windows and doors of masonry buildings was widespread. The wood is hidden from view. The outer wythe (a single vertical thickness of masonry) is an arch, segmental, or flat; the wood is inside.
Many firefighters have been killed while removing apparatus from the collapse zone of a dangerous wall. In one multiple-fatality case, firefighters were removing hoselines from the aerial so that it could be moved. What makes an incident commander smart enough to know that an admittedly dangerous wall will conveniently remain standing while the apparatus is removed? What piece of apparatus is worth a firefighter`s life?
AN INFORMATIVE BOOK
We all learned about the reliability of brick as children from the “Three Little Pigs.” “Built like a brick outhouse” is a common phrase. I observed the weaknesses of “brick” walls years ago when I began taking pictures. Recently, another mentor of mine, retired FDNY Deputy Chief Elmer Chapman, brought to my attention Historical Building Construction, Design, Materials and Construction by Donald Friedman.2 The author is an engineer engaged in restoration and alteration work on buildings in New York City. On page 84, he tells us it was standard practice to use a wooden lintel over windows in masonry walls “where it can be hidden.”
On page 23, he tells of masonry walls with continuous vertical joints. A masonry wall is inherently unstable. Every “return wall,” one at a right angle to the considered wall, is supposed to brace it. This is done by “toothing,” locking the bricks together in alternate courses, thus tying the walls together. This cost time and money. The speculative builders simply omitted the toothing. Since the buildings are row buildings, usually with party walls, the stability is not often affected until one building is removed or destroyed. I have pictures of steel trusses across the void left when one building was removed. Buttresses sometimes serve the same purpose. Apparently, cheating on toothing was quite common.
Now, don`t you non-New Yorkers get smug and say “no such thing in our town.” The people who did the shoddy work moved all over the country teaching their “tricks of the trade,” such as the placing of a wooden beam in the wall as a leveler for the floor beams. The earliest building I have noted with this potential “plane of weakness” was the Paca House built in Annapolis, Maryland, in 1792 and which has been meticulously restored in its original potential-firefighter-killer masonry.
Friedman also tells us that when a building faces on two streets, there will be windows in the side wall, which lessens the wall`s stability because the floor joists are connected to the wall in the relatively small spandrel space between the window openings.
Many of these old masonry buildings were poorly built originally, and they are getting older and more dangerous every day. Sweep your mind of any belief in the stability of brick and stone, and look them over with a critical eye.
The book will be discussed again in a future column, but the author`s knowledge of fire problems is apparently limited. He thinks the letters “UL” refer to United Laboratories.
Chief Nardone`s article reported that the use of high-expansion foam was not too successful on the basement of the shoe store, where the fire on Sixth Avenue started.
I became interested in high-expansion foam early on and was on the National Fire Protection Association subcommittee. The foam originated with a Bureau of Mines engineer who was sent to England to find fault with a British method of fighting mine fires by spraying foam solution onto a brattice cloth stretched across an opening. The engineer instead resigned from the Bureau of Mines and started the High Ex Company. I was interested in the foam for protection of subterranean installations. The Atomic Energy Commission (AEC) had a huge burning pit at the Savannah River Plant for burning trash. For a test, I had it filled with boxes of records dumped helter skelter into the hole 20 feet deep. The boxes were doused with a flammable liquid and ignited. The fire had a very good hold throughout the pile. The fire was controlled with half the water in a 750-gallon tanker–not extinguished. The management wanted the records burned, but the fire could have been easily overhauled. I filled a tank at the Baltimore (MD) City Fire School with rubber tires and easily suppressed the fire with the High Ex foam.
In the AEC, we set up some semi-fixed installations–metal ducts in place to be connected to a truck-mounted unit. It was important to teach the people to leave all doors open. I understand that some plastics can break down the foam readily. The plastic in the shoes might also have contributed to the lack of success in the Sixth Avenue shoe-store fire.
JUST A LITTLE BIT OF PROPANE CAN MAKE THE BUILDING GO DOWN
In my experience, some firefighters and gas company employees tend to take a relaxed or macho attitude toward gas leak responses. In fact, they are extremely dangerous situations. The June 1997 issue of Fire Engineering presented a number of excellent articles on the recovery efforts and the extensive structural damage to an office building in a possible gas explosion that occurred on November 21, 1996, in San Juan, Puerto Rico. There were multiple fatalities.
The article notes that the cause of the explosion is being investigated by the National Transportation Safety Board (NTSB). I called the NTSB several months after the explosion and spoke to an investigator assigned to the case. As yet, there is no report, but he told me that propane gas lines are near the building.
The investigator was unaware, as are most firefighters, of the massive propane explosion that occurred in the Indianapolis Coliseum in 1963 that cost about 75 lives. The story is told in the NFPA Quarterly, the predecessor of NFPA Journal.3
The popcorn concession had popped a lot of corn in anticipation of a large crowd for an ice show. Propane heaters connected to two 100-pound cylinders kept the popcorn heated.
The cylinders were found with their valves intact. It appeared that the heater warmed one of the cylinders enough to lift the relief valve. Enough gas escaped to provide a violent explosion, which caused massive damage to the structure and the deaths of 75 people. One victim, according to a firefighter, was found on the ice, crushed by a huge block of concrete.
Propane and natural gas have no odor, unlike their predecessor, coal gas (also called “city gas”). The odorant, which is added, can be filtered out by passing through the earth.
Gas following an abandoned pipe leaked into the concrete block walls of a supermarket in Orlando, Florida, some years ago. There was no odor. A man flicking his lighter ignited the gas. A chunk of concrete block hit him square in the gut. Fortunately, he was wearing a very large metal belt buckle.
Gas explosions have demolished many buildings. An explosion in England brought down one corner of a high-rise, built according to a “state-of-the-art”4 construction system that literally made the building a house of (concrete) cards. This and other defects caused the entire Ronan Point Project to be demolished.
Propane gas is widely used on construction jobs to keep concrete from freezing and for personal comfort. In most cases, cylinders stand upright without any of the standard protection from falling and breaking off the valve. The open flame “salamander” (burner) is in place to ignite the gas (see picture on page 351, BCFS3). Portable propane stoves are a feature of oriental cooking. A number of serious fires in Pacific Rim hotels were started by mishandled propane. High-flame-spread interior finish and furnishings fuel the fire.
Two Carthage, Illinois, firefighters died on October 2, 1997, and two others were hospitalized, one in critical condition, when a propane tank they were trying to cool experienced a BLEVE5 and tore through the storage building, 60 to 80 feet away, behind which they had taken shelter as they attempted to cool the tank. The 1,000-gallon tank was burning at the vent on arrival.6
Around Christmas time, 1983, the Buffalo (NY) Fire Department was devastated by the loss of the entire Ladder 5 five-firefighter crew and serious injuries to several other firefighters. The units had responded to a call for a 500-gallon propane tank that had fallen off a fork lift, breaking off a valve. As firefighters arrived, the gas ignited, blowing the building apart and burying the firefighters in the bricks.7
A criminally stupid “prank” had disastrous consequences in Pennsylvania. A rescue squad member rolled a propane tank with the valve open into the squad building. A heater ignited the gas, and a squad member/firefighter died in the fire. The culprit was arrested.
In New London, Texas, in 1927, 294 students and teachers died in an unodorized natural gas explosion in the crawl space under the school.
“Taking the gas pipe” was a common suicide method when coal gas was used. Natural gas and propane are not efficient poisons, but not everybody has gotten the word, and some explosions have been caused by would-be suicides.
At the very least, all personnel responding to a gas leak should be fully dressed in protective clothing. Explosive gas indicators calibrated for the gas used should be employed. All personnel should be aware of the hazard of the slightest spark. Some years ago, a San Francisco battalion chief showed me a gas station that had had a serious natural gas leak. He told me he ordered the lights turned out to deter motorists from coming into the station. He was chagrined when I reminded him that turning out the lights can provide that same spark as turning them on. When gas lights were new, signs warned those used to blowing out kerosene lamps, “Don`t blow out the gas.” Don`t let a gas leak blow out your lights!
From time to time, I will present a “war story.” (War stories have gotten a bad reputation; they generally feature an old-timer bragging of his exaggerated exploits to a member of the younger generation. Their use here is to provide useful lessons.) I think it is very important to define your responsibility vs. your antagonist`s when there is a difference of opinion.
A Navy captain was very hostile because of remarks I had made concerning the hazards to my sailor-firefighters during a preplanning visit to a warehouse. He had ignored written reports.
“Captain, I`m a brand new Naval officer, so tell me I have it right. You are in command here, and the Navy will hold you responsible for anything that happens to this warehouse. On the other hand, as I understand it, the Navy has made me responsible for the lives of those six sailors should there be a fire in the warehouse, and there are real life hazards there.”
Note my polite deferential tone. The captain, recognizing that in Navy parlance, I had “put his finger on his number” (set him up for the fall if anything happened), replied, “If it`s that bad, we had better do something about it.” My status had changed from a smart-ass civilian in uniform to a conscientious junior officer who understood his job (to take care of his people), as he later told my boss.
At the Norfolk Naval Hospital in Portsmouth, Virginia, three years later, I had a much higher rank, three years experience, and the assured backing of the Admiral. The executive officer (a medical corps captain) was livid over the “waste of money which he had to go back to civil life and pay taxes for.”
The “wasted” money was spent to install an outside steel fire escape from the third floor of a wooden building with two interior stairways leading into a bowling alley (hazardous occupancy–flammable liquids). Three hundred Navy wives would meet on the third floor to roll bandages. I told him: “When I enlisted, you people jabbed me with needles, saying, `We know what`s good for you.` We just did the same thing to you.”
He turned on his heels and left.
The AEC`s Division of Military Applications had combination locks on all doors. It refused to provide the combination to the guard force, as was the practice. There was a great quantity of paper exposed all the time.
The director, an Army general, put out an order: “In the event of a fire, the duty officer will be called from home. He will open the office and extinguish the fire.”
My letter in response: “This is a dichotomy.8 You will not let the firefighters into the room, and your duty officer will die if he follows your order. This is no problem to me in regard to my responsibility for the building, as I have arranged for the fire department to throw water in through the windows from outside. When the water flows over the windowsills, we will be assured that the fire has been extinguished, without entry.”
Recognizing the hazard to his career, he called me for assistance in solving the problem. Note that I was now not an antagonist but an advisor helping him out of a problem that could have been a career-wrecker.
Nothing works every time. In 1971, Montgomery College, where I was teaching, adapted the former library as a computer facility for all the college records. I looked at it and noted several problems.
I told the director, “I just came from the AEC, where we had the world`s best computer fire protection.9 I will be happy to ask our computer expert to come down and make some recommendations.”
He wasn`t interested. He replied, “The fire marshal said it was OK.”
I retorted: “The fire marshal`s responsibility here is to see that you get out alive; he is not responsible for the safeguarding of the college records. You are.”
I told the students to save every scrap of paper they received from the college. The records of thousands of veterans are in disarray as the result of a fire at the Military Records Center near St. Louis some years ago. One consequence of the chaotic record situation was that a veteran was dragged from a wedding by MPs because he was mistakenly classified as a deserter. Computer people are now very sensitive to backup protection for records, but it is still a good idea to keep your own records, such as pay and pension information. Such an action may be significant years from now. n
1. This refers to a sixth alarm on Sixth Avenue, renamed Avenue of the Americas in 1940. WNYF is an official training publication of the City of New York Fire Department, which may be reached by writing c/o Robert Scott, FDNY, 9 Metro Tech Center, Brooklyn, NY 11201.
2. Published by W. W. Norton and Co., 500 Fifth Avenue, New York, NY 10110.
3. “Indianapolis Coliseum Explosion,” Wilbur Wolfe, NFPA Quarterly, April 1964.
4. I have defined “state of the art” as “We don`t know if this will work; we are trying it out on you.”
5. Boiling-liquid, expanding-vapor explosion (BLEVE); see NFPA Handbook, 18th ed., pp. 4-74.
6. Firehouse, November 1997, 128.
7. “The Buffalo Explosion,” Fire Command, March 1984, 28.
8. A government word meaning “being between hell and a hard rock.”
9. We had full automatic sprinkler protection. I developed a videotape with Don Keigher, SFPE Fellow and recipient of the NFPA`s prestigious Lamb Award, that showed the hydrophobic computer nerds that water was preferable to fire.
FRANCIS L. (FRANK) BRANNIGAN, recipient of Fire Engineering`s first Lifetime Achievement Award, has devoted more that half of his 56-year career to the safety of firefighters in building fires. He is known for his lectures and videotapes and as the author of Building Construction for the Fire Service, Third Edition, published by the National Fire Protection Association. Brannigan is an editorial advisory board member of Fire Engineering. He may be reached at (301) 855-1982.