A Fire Chief’s Views on Building Construction
Chief Taber Talks to Boston Engineers on Design from Fire Hazard Standpoint—Points Out Some Defects and Urges Consultation with Fire Department on Building Problems by Architects and Engineers
IN the following paper which was read before a meeting of the Boston Society of Civil Engineers, Chief Taber gives the engineers his views as to what form building construction should take from the fire prevention standpoint. The chief has incorporated in this paper the practical ideas which his long experience as a fire-fighter has given him as to the best methods of securing safety from fire in business structures:
We have an exceptional opportunity here in Boston to study progress in building construction and design. The area lying between Washington Street and the harbor, and bounded on the south by Summer Street and on the north and west by Milk and Oliver streets, is roughly the area burned over by the Great Fire of 1872. The great bulk of the buildings in this area were built in the ten-year period following that fire, and so may be considered as representing the best in construction and design of the time.
Front the fireman’s standpoint the architects of that day did not give any large thought to fire protection in the design of their buildings. Of course, so far as the materials went they did not have the steel and concrete which we have today. Take Federal Street for example. Of the buildings on that street erected after the Great Fire there is hardly one which has since escaped having a serious fire.—a fire in which the design of the building played a considerable part. The architects of fifty years ago did learn from the Great Fire that party walls must be thicker and heavier, and they eliminated the ornamental but usually highly combustible superstructure called the mansard roof. They gave little thought, however, to protecting their stair openings and such elevator shafts as existed at that time. Their buildings have proven to be generally structurally strong in the sense that the walls in them have not been carried down by the giving way of the floor timbers as they were burned off. You may not realize it, but at a serious fire in an old building the chief has to give very serious thought to the protection of his men from destruction by an early weakening of walls and timbers.
Exposure from External Fires
A great many laymen seem to think that what we know as a fireproof building is a perfectly safe proposition; they don’t think of the contents of the building—and the contents of a building are just as combustible today as they were fifty or a hundred years ago, and they always will be, in the very nature of things. In our modern building, so far as fire protection and design go, we have two objects, first, to protect the contents from fire originating without the building—that is, outside exposure—and second, to protect the contents from an undue spread of the fire within the building itself.
“To begin with, we want good solid party walls which will withstand any heat to which they may be exposed, and which extend well above the roof. The difficulty in our front and rear and in light shafts, areas, etc., is coming from windows, and here everything depends on the exposure. I think we can take a page from the naval constructor’s book, and divide our building into firetight compartments as he divides his into watertight compartments. I am going to suggest that you put in this building, if it is a mercantile, manufacturing or warehouse building, another device of the sea—the ‘smoke telltale’.”
A number of years ago we bad a most peculiar fire in Boston—the Hotel Lenox fire. The building itself was non-combustible. It was divided into a large number of comparatively small rooms, and it had no Contents which could develop a heavy body of fire. In the early hours of the morning a cigarette smoker set his bed afire. Without thought he rushed from his room, leaving the windows, door and transom open. Dozens of other guests did the same. A most wonderful series of drafts were set up. and the impossible had happened. It was a five-alarm fire, which resulted in no serious structural damage to the building but did result in a serious damage to contents. The fire originated on the third floor, and performed the peculiar feat of going out of the windows and back in on the fifth floor again. Now, if that cigarette smoker, when he set his bed afire, had closed his windows and then left his room, closing his transom and door, a chemical line probably would have extinguished that fire and the damage would not have extended beyond one room.
(Continued on page 1281)
Chief Taber Talks to Engineers
(Continued from fage 1258)
You all remember this fire; I have simply brought it up to illustrate what we want to avoid in our buildings as much as possible,—that is, the creation of drafts.
To begin with, we want good solid party walls which will withstand any heat to which they may be exposed, and which extend well above the roof. With these provided we have more or less automatically confined the fire to the building where it started, so far as the buildings on either side are concerned. The difficulty in our front and rear and in light shafts, areas, etc., is coming from the windows, and here everything depends on the exposure. The Chicago, Burlington & Quincy Railroad office building in Chicago, two years ago, is a good example. The building, a comparatively modern fifteen story office building, had the seemingly good exposure protection of an eighty-foot street (our own Federal Street is sixty feet from building line to building line), and wire-glass windows had been thought unnecessary. To make a long story short, the heat generated by the burning of some comparatively low combustible buildings was sufficiently intense to break these Chicago, Burlington & Quincy windows, let fire and heat within, with the net result of a five million dollar damage to their building and its contents. In other words, if there is any doubt in your minds about exposure hazard in your building, give the future contents of that building and the fire department the benefit of the doubt and put in wire glass. Where there is close exposure to the possibility of heavy fire, I should like to see both wire glass and standard shutters. Normally the shutters will generally be open during daylight hours, and at least part of the windows will be closed, so that the wire glass will be a tremendous help until the shutters can be closed. I should advise this on narrow streets, areas, light wells, etc.
Design within the Building
Now we have got our outside walls pretty well protected. What are we going to do on the inside? Here I think we can take a page from the naval constructor’s book, and divide our building into firetight compartments as he divides his ship into watertight compartments. In the first place, let us design our building with the idea of preventing the vertical extension of the fire. In the modern building this means, in general, the elevator shafts and stair wells. If we make these so fire-tight that fire cannot get into them from the surrounding areas, and vice versa, we will accomplish our object in an ideal way. Then our elevator shaft (non-combustible of course) will contain not only our elevators but a landing place at each floor, rather than having our elevators open directly into the floor areas themselves. Designed in this way, if space permits we get a double protection; first, the protection of the walls and doors of the shaft, and second, the protection of the wired glass forming the front of the elevator well proper. Now through these walls we have got to have doorways to give access to the floor areas. To do us any good these doors must be as good or better than standard tin-clad, and should be normally closed. In buildings carrying contents capable of developing a heavy body of fire it is going to be a big help, in confining the fire, if we have the protection of two doors, one of which is normally closed during the daytime and both of which are normally closed at night, and both of which will automatically close when tripped by some device in the watchman’s office. Fusible links are a good thing to release a fire door, but they are, of course, absolutely no protection against the spread of smoke, and when the atmosphere is getting up around the 150 or 160 degrees of heat necessary to make them function, it is getting too hot to be real comfortable or safe. I want to see the doors in this building of ours close when the alarm is given, and stay closed except when opened for necessary passage through. The bulkheads on a ship are closed at once in case of a bad leak, or in case of fire; they don’t wait until the water is a certain depth or a certain degree of heat has been reached. Why shouldn’t we provide means for more or less automatically closing up the various parts of a building as much as possible immediately a fire breaks out? Every door we close eliminates one draft.
If we have done all the things I have suggested we have more or less cut off the immediate spread of the fire from one floor to the other. The next thing is to keep it in as small a portion of one floor as we can. In an ideal design we shall divide our floor areas by fire walls, capable of withstanding any heat to which they may be subjected, so that the floor area between fire walls will not be much over half an acre in extent. Of course these areas will have to have doorways to the adjoining areas on the same floor, and, of course, we shall protect these openings by as many and as good doors,—operated by the same closing devices that we used on our doors into the elevator shaft.
I have given you briefly and very roughly, and without going into details, my ideal of a building from a fireman’s standpoint. Of course it is either of non-combustible properly protected construction or else mill construction. In either event, if cut up and protected as I have indicated it will be ideal from a fireman’s standpoint. The handling of a fire in such a building, regardless of occupancy, except explosives, will be child’s play compared to what we are up against today. Of course, in painting this ideal I realize that you cannot follow it explicitly in an office building, but in general principles it can be followed even in an office building. You can follow it fairly closely, however, in mercantile and absolutely in manufacturing and warehouse buildings.
Ideal Fire Protection
Now, I am going to suggest that you put in this building, if it is a mercantile, manufacturing or warehouse building, another device of the sea—the “smoke telltale.” Briefly, it is a series of tubes leading to the pilot house through which air is drawn front each compartment. A telltale wisp of smoke discloses the fact that there is a fire in compartment so and so. You can get the idea in its refinement and detail by getting in touch with the chief engineer of almost any large ocean-going liner. Of course, on land the pilot house would be the watchman’s office—and here also would be our devices for tripping the fire doors and here also will be a city fire alarm box. When our watchman during the night gets a whiff of smoke from one of these smoke protectors, the first thing he does will be to pull that box. Next, he will have an elevator or elevators ready to operate to the floor from which the smoke comes. Ot course we have installed in this building six-inch standpipes with outside connections,—raise your outside connections a couple of feet above the sidewalk to get them out of the snow and ice. Then when the fire department arrives he is on the sidewalk to tell the chief that he gets smoke from the eighth floor, right-hand rear compartment. He also has available a chart showing the fire walls and doors and interior partitions on that floor. Next, we are on an elevator with two or three lengths of hose which we will connect to the standpipe on the eighth floor. In the meantime, the outside connections are being connected by hose to the nearest high-pressure hydrant. Simple, isn’t it, this fireman’s dream?
Just a word as to particular classes of buildings. Big unbroken floor areas are the bogey man of the fireman’s existence; they seem to have been a necessary evil of the department store. A large part of the contents of the department store are highly inflammable, and of such a character that fire travels flash fashion. I hope that our future department store buildings will have their floor areas more subdivided than they are today, and that every floor will be well cut off from the floors above and below it. I am not an architect or an engineer, but it seems to me that these great floor areas could be subdivided without any large loss of efficiency as a store plant. Think it over carefully when you have a store building to design.
Now, again, remember that in a building where large quantities of absorbent material are apt to be stored, it is desirable that you provide means of egresS for some of the water we may have to pour into the compartments of that building. Leaving out the element of relieving the load on the building, it’s going to help a lot in lightening water damage, for what runs out through scuppers or other means won’t soak down on to the other floors.
Today a single alarm in the down-town district brings to the fire from ten to fifteen vehicles of major fire-fighting apparatus, including perhaps ten thousand feet of hose. Think of it! If the fire has much of a start this quantity of apparatus may he doubled, tripled or quadrupled, and still the fire may not be anywhere near a conflagration, but may involve only one comparatively small building and its contents. When our present old buildings are replaced with these ideal buildings which you and I are planning, it is going to take a considerable fire to bring out more than a couple of high-pressure wagons and a couple of ladder trucks. What is your guess as to when that will he brought about? I am afraid that none of us and perhaps none of our children will see it accomplished completely.
Remember, if you will, that fire is a good deal like a rat—it will eat its way out if it can; drafts of air help it to eat its way out if it finds any part of the building to eat on. Design and construct your building so that you can keep a hungry rat in or out of any compartment you choose, and, except for thickness of various compartments, that will furnish a pretty fair test of whether a fire department can confine a well-developed heavy body of fire to that same compartment, always bearing in mind that the structural members, if metal, must be properly and sufficiently protected from the heat generated by the fire, and if of wood, must be so large as to be slow burning.
What I have suggested contains nothing original. So far as design goes all these suggestions were long ago used in our best type of so-called “mill construction.” We get a whale of a fire in the firebox of a boiler or in our kitchen stove, but it stays right there. The boiler or the stove does not burn up. The fire in the cook stove does not get into the oven. That’s what we want to accomplish in our buildings. We are bound to have our furniture and merchandise get on fire occasionally. Properly designed and constructed, however, there is no reason in the world why the building itself should be seriously damaged, or why the contents of any large part of the building should be damaged or destroyed.
Boston Fire Department
Boston is probably no different in its general combustibility from all of our cities. We have here what you will pardon me for believing to be the best fire department in the country. It is as economically operated as it can be, but its very size makes it an, expensive proposition, and its size is not too large for what might happen any hour of the day or night. Out of every dollar the city pays out. approximately six and one-half cents goes for the maintenance and operation of the fire department. This does not include any interest on the capital invested in houses, apparatus, alarm systems, water mains, pumping, plants, etc.—it includes simply the operation and maintenance of the department. Think of it, six and one-half cents of every dollar paid by the city of Boston! That expense or greater must continue for a great many years, or until the great bulk of our old buildings have been replaced with buildings which resist fire. Then and then only can we cut our fire department down, both in men and apparatus. That time is coming, but none of us will live to see it.
We firemen haven’t had your education and technical training, but by and large we have had a good deal of practical experience in seeing what fire will do. The modern fire department is just as much interested in preventing a fire or in retarding a future fire as it is in putting out an existing one. We haven’t the least bit of worry that fire departments will be found unnecessary and that we will be out of a job. Our salaries don’t depend on the number or the sizes of fires. In other words, if our practical experience is of any value to you in helping to prevent the extension of future fires, come around and put up your problems to us, and we will give you any help we can in solving them.
Vinita, Okla., Standardizing Equipment—All hose, hydrants, and fittings of the fire department, are being standardized at Vinita, Okla., a town of about 6,000 population.