When beginning the task of designing a fallout shelter, the prospective builder is faced with a number of different options. The builder must decide first which particular type of shelter envelope system or structural shell is the best suited to his needs. Once this important decision is made, the rest of the peripheral design considerations will start fall ing into place. To be or not to be underground—that is the question that Americans should be contemplating in this day and age. The choice is either a basement shelter or an underground shelter. There are many types of fallout shelters, and the type that is best for you can be determined only by your needs. There are a number of different fallout shelter options available.

Underground shelters give the maximum protection against radiation, heat and blast. Some of these options include: conventional reinforced concrete, concrete blocks, steel reinforced concrete domes and barrel vaults, metal culvert, used metal fuel tanks, metal quonset structures, concrete sewer line pipe, pre-made fiberglass, and wood framed expedient shelters. Some people have even buried old school buses. When these below ground shelters are covered with at least three and preferably ten feet of earth, they provide an excellent pro tection factor against fallout radiation. Dirt is dirt-cheap and covering an underground shelter with 10 feet of earth is the least expensive way to achieve maximum shielding. If properly constructed, underground shelters offer good blast protection. This is especially true for the steel reinforced concrete domes and barrel vaults that have exceptional geometric strength characteristics due to their arch design. An underground shelter will give you a fighting chance in a worse case scenario.

No one system is going to be the best system in all environments, under all circumstances and considering all budgets. In fact, a shelter can contain combinations of a number of these options. The following section will examine the most basic shelter types with the intent of educating the reader so he can make his own decision.

Fuel Tank Shelter

Advantages

If you are an accomplished welder, (or have someone in your shelter group who is) a steel tank shelter may be your best option. The advantage of fuel tank shelters is that used steel fuel tanks are relatively inexpensive to purchase. They can, to a limited extent, be internally outfitted in a shop before actual burial. Also, steel tanks can provide EMP (electromagnetic pulse) shielding. Steel tanks are generally watertight and can be used in areas where high water tables exist. It is much easier to weld and join together steel tanks than culvert.

If you are not an experienced welder and you intend to build a tank shelter, I suggest you research and purchase a good wire feed welder. Wire feed welders are much easier for novices to work with than arc welders. A Hobart wire feed welder costs about $1,200 new.

Disadvantages

There are certain disadvantages to steel fuel tank shelters to consider. They are a
confining space, generally limited to 10'6"
di ameter and require a floor system. Steel tanks have very little integral strength and are dependent on earth arching to remain struc turally intact. Backfilling has to be done very carefully with optimum compaction.

Please note that cutting into a used fuel tank is an extremely dangerous operation. (Full precautions are given in the next chapter.) It can also be very difficult to clean the inside of a used diesel tank. Used fuel tanks can be rusted through in spots. New tanks are quite expensive.

Backfill and Compaction

One large shelter project, which I am personally involved in, successfully bur ied eleven steel tanks. I have friends who built tank shelter complexes which suffered severe deflection and shape distortion due to settling. This is usually a result of poor compaction during backfilling. The backfilling of steel tank shel ters has to be done with optimum compaction of carefully selected or screened fill. Also, compaction cannot be accomplished when temperatures are freezing. When air temperatures are freezing, the application of pressure on the fill material does not produce com paction, but instead produces ice crystals in the soil. This may produce the false appearance of compaction, but when the spring thaw comes, further settling and de flection of the tank or culvert will result.

Steel tanks can also suffer severe deflec tion and shape distortion if someone drives a heavy loader, backhoe or bulldozer over, or too close to, a partially buried tank or culvert.

Any rock bigger than a softball that is buried within two feet of the tank, may even tually be forced by settling pressure directly against the tank and produce a deforming dent. Also large rocks, chunks of concrete, wood, or other debris buried next to the shel ter when it is backfilled will cause differences in ground structure compression. This is a specific concern if the shelter is a blast shelter that is designed to withstand extreme over-pressure.

The ideal way to control compaction and prevent deforming is to take some special steps during excavation. The hole for the tank should be only dug down to the spring line or equator point of the tank. At this point, the remainder of the hole should be shaped to accommodate the rounded bottom of the fuel tank. The tank should then be placed in the hole and 3/4 inch minus gravel can be vi brated down around the sides into any unfilled voids. Instead of 3/4 inch minus gravel, a mud mixture can be slurried down around the un derside of the tank. Such a slurry should be high in sand content and low in clay and the ground underneath needs to have good per colation. The danger with such a mud slurry is that the tank can float up out of the hole.

If you place a tank in a flat-bottomed hole, which has been dug to its total intended depth, it will be difficult or impossible to get adequate compaction on the underside of the tank.

If you are intending on internally outfitting a fuel tank before it is installed in the ground and back-filled, be aware that the tanks tend to flatten out on the bottom once the backfill settles. This is more pronounced with 12 ft. diameter tanks. The ramifications are that any braces used to support the floor or
partition walls will bend and end up not being at their originally intended level or position. Also, pre-framed doors will end up out of square and not closing. The curved sidewalls of the tank, due to overhead pressure, will tend to expand away from pre-fitted partition walls leaving a gap. This same settling effect will put pressure on top of any pre-fitted partition walls and bow out the surface of the wall. Using great care during the backfill process will minimize these problems but not eliminate them.

Cleaning

As I previously mentioned, cleaning the inside of a used diesel tank can be a big and messy job. Used diesel tanks tend to have a fairly thick coating of hard, pasty residue on the inside walls and puddles of liquid diesel on the floor. We resorted to scraping the inside walls with a flat shovel to get this
accumulated coating off. The liquid diesel can be easily soaked up with sawdust and then shoveled into old feed sacks for disposal. Make sure you dispose of the material you clean out of the tank in an environ mentally safe manner. Used gas tanks are generally fairly clean on the inside, but have a greater tendency to be rusted.

Arthur Robinson is the preeminent authority on shelters made from fuel tanks. He is the author of "The Fighting Chance" Newsletter. Plans can be pur chased from him for fuel tank shelters. Contact the Oregon Institute of Science and Medicine, P.O. Box 1279, Cave Junction, Oregon 97523.

Sharon Packer, with the Civil Defense Volunteers of Utah, has a 160-page booklet on aspects of shelter building that includes an excellent section on steel tank and culvert shelters. This booklet is $20 postage paid and can be obtained by contacting her at (435) 657-2641.

Cold Formed Steel Rib System (information covered in book)

Shipping Containers (information covered in book)

Shipping Container Advantages (information covered in book)

Shipping Container Disadvantages (information covered in book)

Culvert Shelters (information covered in book)

Culvert Shelter Advantages (information covered in book)

Culvert Shelters Disadvantages (information covered in book)

Backfill

Rocks backfilled too close to the outside surface of a buried fuel tank produce large dents on the inside and hitting them with the bucket of a backhoe also produces large dents. This is not the case with culvert. None of the culvert shelters I have seen have shown any signs of point loading dents caused by rocks being backfilled too close to the outside surface of the culvert. Also, experience has shown that culvert does not buckle and dent when bumped by a backhoe bucket.

Backfilling has to be done very carefully with optimum compaction. There have been some serious instances of deflection as a result of the settling of the earth that was backfilled over the culvert. As we previously discussed concerning steel fuel tanks, paction cannot be accomplished when tem peratures are freezing. The ideal way to control compaction and prevent deforming is to take some special steps during excavation. Please see the previous discussion at the beginning of this chapter under Tank Shel ters, Backfill and Compaction.

If you place a culvert in a flat-bottomed hole which has been dug to its total intended depth, it will be difficult or impossible to get adequate compaction on the underside of the culvert.

Even with the best compaction and back fill, culvert manufactures say you should ex pect about 10% deflection. This means that any internal doorways and wall structures that are fitted tightly to the inside curve of the culvert will eventually become com pressed. Cabinets fitted to the original inside curved surface of the culvert will displace themselves from the walls when the culvert squats due to settling and changes its internal curved shape. The punch line is either wait a year or two after backfill and subsequent set tling to internally outfit your culvert shelter, (I do not recommend such a delay), inter nally outfit the shelter without wall and ceiling attachments which would be ef fected by the settling or build a steel reinforced concrete shelter.

Steel Quonset Shelters (information covered in book)

Steel Quonset Shelter Advantages (information covered in book)

Steel Quonset Shelter Disadvantages (information covered in book)

Pre-made Fiberglass (information covered in book)

Pre-made Fiberglass Advantages

The great feature about this system is that it comes completely internally out fitted from the factory. All of the life support systems are pre-made at the factory. This includes air filtration, water storage, entryway, sewage system, power and observation tower. They can be used in areas where a high water table exists, and often can be ordered, delivered and installed faster than building a comparable shelter from scratch. The advantages to the single-family shelter are that fewer people know about the shelter and ideally the project gets done faster. Another advantage to the single-family approach is that management and decision making are more simplified.

Disadvantages

This system is expensive. It is a confining space and it is generally not conducive to community application. Molded fiberglass shelters have very little integral strength and are dependent on earth arching. Like steel tanks and culverts, backfilling has to be done very carefully with optimum compaction. It does not shield EMP.

Like any other one-room shelter, this sys tem has minimal personal privacy. These shelters have only one entryway. The advantages of two entryways are covered in the next chapter.

For more information on Radius Defense shelters contact Bill Eckhoff at Kleen Air Technologies, Inc., P.O. Box 4145, Frisco, CO 80443, (970) 668-0219, Fax (719) 836-1807, E-mail: katinc@amigo.net, www.undergroundshelter.com.

Conventional Steel Reinforced Concrete Shelters

This type of shelter is basically a concrete box. It is formed up with standard basement wall forms. The roof is made of a thick steel reinforced slab.

Advantages

Most local masonry contractors are familiar with the concepts involved in building a belowground conventional steel reinforced concrete structure. This system does not derive its strength from earth arching and the backfilling can be done without any particular care.

Disadvantages

Conventional steel reinforced concrete shelters require massive steel reinforced
concrete slabs to span ceilings and support the earth cover on top of the shelter. Concrete slab ceilings can only free-span
limited distances without the addition of vertical supports. Concrete shelters do not provide EMP shielding and are not usable in areas with high water tables.

Thin Shell Concrete Technology

This category of shelters includes steel reinforced concrete domes, barrel vaults
and donut shaped structures. All of these structures are different shapes of the same technology. The author has considerable experience with this type of shelter system.
I organized a project in which our group built a barrel vault that was 32 feet wide and 122 feet long with three floor levels. As far as we know, this is the largest underground con crete dome-type shelter ever built.

Advantages

The advantages of thin shell concrete domes and arches are that they facilitate large structures with wide spans. This system capitalizes on the natural geometric strength of an arch. The resulting structure is a very strong shell that is not dependent on earth arching for its strength. Thus, no particular care is needed when backfilling these shelters.

Disadvantages

The disadvantages of this particular system are that it does not shield EMP and it is not usable for areas with high water tables. Concrete is applied with shotcrete equipment. Shotcreting is expensive and takes substantial amounts of manpower to accomplish. The kits for the shell of these structures are fairly expensive.

The large concrete barrel vault shelter shown in the pictures was built by the author and his friends. The shell is made from a kit supplied by Earth Systems, Inc. (E.S.I.). This company is no longer in business. There are at least two other compa nies in the United States which make steel reinforced concrete dome kits.

Terra-Dome (information covered in book)

Terra-Dome Advantages (information covered in book)

Terra-Dome Disadvantages (information covered in book)

Monolithic System

The Monolithic system involves in flating a balloon form and then spraying urethane foam on the inside surface of this form. Steel rebar is then attached to the resulting inside surface and concrete is sprayed over the rebar, again from the inside of the balloon form. The resulting product is a steel rein forced dome, with foam insulation and the original form balloon becomes a fixed waterproofing barrier. The newest product from Monolithic is a small concrete pod like dome that is pre-made and deliverable by truck. This small dome can be either buried or used above ground.

Advantages

This system has the same advan tages as other thin-shell concrete domes. Another advantage to the Monolithic system is that it has built-in water proofing.

Disadvantages

The disadvantages of this particular sys tem are that the kit is relatively expensive and the expensive balloon form can’t be reused for another project. Another potential disadvantage of this system is the foam insulation. The foam insulation is probably an asset for a sub-earth home or an above ground structure. If, on the other hand, you are building an underground shelter, the foam insulation will restrict the conduction of heat from the inside of the shelter to the surrounding earth cover. Heat build-up is a potentially serious problem in crowded underground shelters, as we discuss in the chapter on Air Supply.

Prices and information on the Monolithic Dome system can be obtained by contacting Rocky Mountain Dome Co. HCR 85, Box 170M, Bonners Ferry, ID 83805, (208) 267-8596, Fax (208) 267-1037.

Home Grown Options (information covered in book)

Grenier - Barbier System

The first system in the home brewed category is what I call the Grenier - Barbier sys tem. Mark Grenier is a close friend and a master builder. He built a donut arch system designed by Marcel Barbier, who is a well-known engineer in the civil defense field. The form was made of redwood boards that were steamed and bent over a wooden rib system. The outer surface had rebar tied over it and concrete applied. The resulting structure was then waterproofed and backfilled.

Advantages

This system has the same advantages as thin-shell concrete domes and barrel vaults. Other advantages to this system are that there are no kit costs and the interior surface is beautifully finished redwood. For a larger shelter, the donut shape has the optimum geometric shape.

Disadvantages

The disadvantage with this system is that the process of steaming and bending redwood boards is very labor intensive and the form is not reusable.

Newhouse System

Another home brewed system is what I call the Newhouse system. This system was devised by a friend of mine named Dave Newhouse. Dave built tract homes for about 30 years before he started building underground shelters.

After building concrete dome sys tems from expensive E.S.I. kits, Dave and I started contemplating how we would do it if we had to do it over again. The whole idea was to get away from the expensive kit and the labor-intensive shotcreting. Dave came up with a new system that involved making your own form system with plywood and two-by-fours.

Advantages

The forms for this system can be reused over and over again. Shotcrete equipment is not needed for the Newhouse system. The concrete can be applied to the structure by a concrete pump truck. This reduces the labor by about two thirds, and the pump truck costs a fraction of what shotcrete application costs. As I mentioned earlier, for an E.S.l. system you need to apply the concrete with shotcrete equipment.

Disadvantages

The disadvantages of the Newhouse system are that it does not produce a finished interior surface, and the home brewed systems in general are not as easily configured for arches larger than 33 feet in diameter.

For Newhouse Shelter plans contact Yellowstone River Publishing, P.O. Box 206, Emigrant, MT 59027, (800) 327-7656.

Basement Shelter

Probably most civilian shelters are in basements. A well-built basement fallout shelter will provide a protection factor of about 100 against fallout radiation. (See chapter on Radiation Shielding.)

Advantages

A basement fallout shelter is probably the most cost-effective type of shelter. These shelters can be more easily concealed. Basement-type shelters make use of an exist ing structure and in some cases, the sewer, water and gas. If you already have a basement and are not in close proximity to a target, this may be your best option. It is much easier to make effective dual-use out of a basement shelter such as doubling as a family room, recreation room or storage. Your basement shelter is so close that it is much easier to get yourself and all necessary supplies in there on short notice. A basement fallout shelter can provide protection from the initial thermal effects of a detonation. In the event of a nuclear attack, basement fallout shelters could provide adequate protection for the majority of the American people.

Disadvantages

Basement shelters do not have blast protection. In the event of overpressure, the house may be reduced to rubble, covering up or destroying the shelter. In the event that the shelter didn’t have a dedicated subterranean exit leading away from the house, the occupants would be trapped. If the blast-generated rubble ignites, high temperatures will be produced right on top of the shelter. Heavier than air gases like carbon monoxide would penetrate non-airtight shelters, killing the occupants. Carbon monoxide poisoning killed most of the people who died in basement shelters during World War II.

Home basement shelters are generally not applicable for community shelters because they are usually small spaces. Basement shelters don’t offer the same protection as buried shelters when it comes to earthquakes and high winds.

Instructions on Building a Basement Shelter (information covered in book)

Air Flow into a Basement Shelter (information covered in book)

Enhancing Basement Shelter Shielding (information covered in book)

Expedient Shelters (information covered in book)

 

Government Designated Public Shelters

What about public shelters? You know those designated public civil defense shelters, usually located in basements of schools, banks, etc.

Advantages

No cost to the using party.

Disadvantages

No deposit, no return. Unfortunately, these so-called shelters will tend to be a place where the average American family will find lots of death and misery for company. Very few public shelters have any emergency stores of food, water, medical supplies or back-up power. None have air filtration capabilities and most will not have working sanitation facilities. When the state civil defense agencies started surveying buildings for use as potential public shelters, they found that there weren’t enough structures to accommodate all the people who needed to be housed. The government’s solution was to lower the minimum protection factor so more buildings would qualify.

The United States Civil Defense pro gram, for all intents and purposes, exists only on paper. The bulk of the program involves the mass relocation of people in critical target areas to rural areas. The problem with this plan is threefold. First, a one-week advance warning is needed to implement the relocation. Second, all these people would be moved to areas without adequate shelter, food, sanitation facilities or sources of drinking water. Finally, most of these relocation areas will be contaminated by windborne radioactive fallout.

Shelters for the Elite

Be assured that the U.S. government has been and still is spending billions on secret shelters for important federal, state and corporate officials. Mount Weather is a virtual underground city located near Bluemount, Virginia, 46 miles from Washington D.C. and is officially designated the Western Virginia Office of Controlled Conflict Operations. The Mount Weather staff includes a working duplicate of the Executive Branch of the Federal government and is the central command center for F.E.M.A. It is interesting to note that a privately owned profit corporation, the Federal Reserve, also has an office in Mount Weather. In the event of war, the declaration of martial law or other national emergencies (potentially including serious financial or political crises), the President, the cabinet and the rest of the Executive Branch would be relocated to Mount Weather. Believe it or not, Congress has little knowledge of this facility and absolutely no budgetary oversight.

In all fairness we shouldn’t be too hard on our elite bureaucrats for trying to save their own necks. After all, the Soviets built blast hardened facilities for the KGB, their military command and top party officials; (they obviously are not expecting a nuclear war). Most recently this includes the huge Yamantau complex in the Southern Ural Mountains area of Beloretsk. This complex is purported to be as big as the area inside the Washington beltway. It is not a relic left over from the cold war, but was constructed under Yeltsin’s direction. Not bad for a bankrupt country that needs aid from the U.S. to pay for it’s own compliance with disarmament treaties. The one thing we can say for the Russian elite is they seem to value their civilian cattle more than their western counterparts. The Russian leadership has built shelters for 70 percent of their civilian population.

My suggestion to every American is to not base your preparedness actions on the government’s assurances that all is well, but take a cue from the course of action that the government has quietly taken.

If you want to know more about the billions of tax dollars that has been spent on government underground shelters obtain a copy of the book: Underground Bases and Tunnels: What is the Government Trying to Hide? by Richard Sauder, Ph.D. (Available from Adventure Press, PG Box 74, Kempton, Illinois 60946, (815) 253-6390, $15.95, plus $2 s/h).

Small Versus Large Shelters (information covered in book)

Sub-Earth Home With Dual Use Shelter (information covered in book)

Mines, Tunnels and Caverns (information covered in book)

Mines (information covered in book)

Tunnels

Railroad and highway tunnels offer the possibility of large-scale emergency shelters. The Swiss have a long high way tunnel which they have outfitted with a blast door, ventilation, emergency power generation, sanitation and stored beds and supplies to accommodate 7,000 people. In most cases utilizing a highway or rail tunnel will be limited to a government-organized project. The local rail company and the state highway department might not be too excited about you and your friends commandeering a tunnel, especially for a drill, but it is conceivable that a group of citizens could make use of a tunnel in an emergency if they did a little preplanning.

If you were to drive in a water truck, a trailer full of porta-potties, and a truck full of food from your local grocer or other sources, you would have all the basics for an expedient tunnel shelter. The only other essential ingredients would be a backhoe, sand bags (or feed sacks), and shovels. The backhoe would break up the compacted earth, and there shouldn’t be any shortage of volunteers to man the shovels, and fill and stack sand bags. If an 8 to 10 foot high by at least 4-foot deep sandbag barrier was constructed on either end of the tunnel, you could obtain reasonable shielding against radioactive fall out. People can shovel a lot of dirt in a real short time when their lives depend on it.

The open space between the top of the sandbag barrier and the roof of the tunnel on either end would facilitate ventilation and minimal lighting during the day. Have everyone bring their sleeping bags and camping gear, and have a two to three week campout.

Caverns (information covered in book)

A shelter project, like any other project, can seem overwhelming at the onset. A large, intimidating shelter project can be tamed by segmenting the project into smaller manageable units such as the shell, air system, power system, lighting system, water supply, etc. Deal with the project a segment at a time. And remember, what man can conceive and believe, man can achieve.

Space Requirements

Space requirements for shelter occupants should be considered from both a basis of square footage per person and cubic feet per person. The U.S. Government publications recommend a minimum of net 10 square feet per person. Net square feet is floor space that can also include walls, bunks, storage and fixed equipment. Try living in 10 square feet for two weeks, especially with children. What if it ends up being 60 or 90 days? Some of the larger shelters I am aware of have up to 50 net square feet per person.

Design Specification Questions

The following are questions, which when answered, can stimulate creative thinking and bring to light considerations that the first time shelter builder may have overlooked.

1.How many people is the project going to accommodate?

2.How many family groups does the above number of people represent and what sizes are these groups?

3.Do you want private rooms for family groups?

4.Where, generally, is the shelter going to be located?

5.Do you want blast protection or do you want fallout protection?

6.How long do you want to be able to remain in the shelter without having to come out? One month, two months, three months, nine months, or more?

7.How much of a food supply do you need to stockpile in or near the shelter? One month supply, two months, six months, one year, or more?

8.Do you want a separate clinic room in the facility?

9.Do you want to try to shield your sensitive electronic equipment from electromagnetic pulse?

10.Do you intend on having communication equipment, (i.e. shortwave, ham, etc.)?

11.Do you intend on having a decontamination area?

12.Do you plan on having a crawl-in or a walk-in entry way?

13.How deep are the wells in the area where the shelter is going to be built?

14.Do you want a pressurized water system with an electric well pump or do you want a hand pump or both?

15.Do you want hot water and flush toilets?

16.Do you want both a men’s and a women’s bathroom, or one bathroom?

17.Do you plan on having a water storage cistern?

18.How big of a cistern, in terms of balloon capacity, do you want or need?

19.How long do you want to be able to run your generators, (i.e. how long do you want the fuel to last)?

20.Do you want to have an extra generator for back up?

21.Do you want to incorporate the ability to run on battery power into the shelter’s power system?

22.Do you want battery power as an emergency reserve or as a primary operating source?

23.How long do you want to be able to run on battery power without recharging the batteries?

24.Is the site for the shelter such that the shelter can be built into the side or into the top of a slope?

25.Are you concerned about the security of your shelter in the event of an emergency occupation?

26.Do you want to have an observation tower incorporated into your shelter which would enable you to have some control of the perimeter around the shelter site?

27.Is the shelter going to be connected to or part of any above ground structure?

You probably don’t have the answers to many of these questions but hopefully they have caused you to consider some important aspects of shelter building that you hadn’t thought of before.

Site Location Considerations

Proximity to Target Areas

When standing on railroad tracks, if you observe an oncoming train, the logical thing is to get out of the way. If you believe in the possibility of an oncoming nuclear war or natural disaster, the logical thing to do is to relocate out of any target areas or any potential area that could be drastically affected by earth changes. If you live in the crime dominated inner city, what would be a better investment: buying bullet proof vests for your family or moving to a better neighborhood? In the same fashion, building a blast shelter because you live near a known target area, might not be as smart as moving to a non-target area (perhaps as little as ten miles away) and building a less expensive fallout shelter. When you see a locomotive coming down the tracks toward you, the most cost-effective thing you can do is get out of the way.

In order to be effective, shelters in target areas must be blast hardened; built to withstand the direct effects of a nuclear weapon. Even if you have a blast shelter, your first indication of a threat might be the flash of a strike. At that point, it is too late to run to your shelter.

It is my personal opinion that if you determine that you need blast protection, you should seriously consider relocating. Distancing yourself from target areas and areas of vulnerability has both practical and financial advantages. It is practical in the sense of avoiding the direct effects of a nuclear weapon and financial because building a fall out shelter is less expensive than building a blast shelter. Living close to a target area greatly reduces your chance of survival and greatly increases the cost of a shelter.

The best place to relocate to is a remote area, at least ten miles from any target area, and preferably, thirty miles away from any areas of major population. It would be ideal if this area was in proximity to other like-minded people.

Once a decision is made on a general location of a shelter there are certain factors that should be considered for specific locations.

Available Water (information covered in book)

Drainage (information covered in book)

Depth of Bedrock (information covered in book)

Tactical Problems (information covered in book)

Access (information covered in book)

Earthquake Considerations (information covered in book)

Other Building Considerations (information covered in book)

Cutting Into A Used Fuel Tank

D A N G E R

Extreme caution should be exercised when cutting into a used fuel tank. Over the years, numerous people have been killed by explosions resulting from trying to cut a hole in a used fuel tank. Tanks which contained diesel fuel are less susceptible to explosion than tanks which held gasoline. Old gasoline tanks are extremely dangerous to cut into. Regardless if it is an old diesel tank or an old gasoline tank, treat both kinds as if they were gas tanks. You can never be sure exactly what was in the tank.

A fuel tank does not need to have fuel in the bottom of it to be dangerous. The fuel vapors or fumes, mixed with air, will be ignited by a spark from a metal cutting saw or torch. The intensity of such an explosion can rarely be survived.

There are three ways to prevent fuel tank explosions when cutting into a tank. The first is to use dry ice, the second is to use compressed C02 and the third is to use exhaust off the tail pipe of a truck. The whole concept is to displace the vapor fumes out of the tank with C02 which is a heavy gas. Begin by making sure the tank is standing upright in its natural position. Then, open one of the plumbing access fittings on the top of the tank.

If using dry ice, put 20 lb. of the dry ice in the tank for each 1000 gallons of tank capacity. The temperature has to be warm enough to facilitate the melting of the dry ice in order to produce the C02 gas. Wait until the dry ice has melted completely before cutting into the tank.

If using C02 compressed gas, insert a discharge tube from the tank of C02 into the access hole in the fuel tank and slowly let the gas fill the tank. Use 150 cu. ft. of compressed C02 gas for every 1000 gallons of tank capacity.

N O T I C E

Unless you are knowledgeable and experienced in this area, you should purchase a tank that has already been cut open by a licensed fuel tank remover or purchase a new tank. This information is not intended to be encouragement or advice from the author in regards to cutting into a tank. If you decide to engage in such a dangerous and unpredictable activity, you will have to do it at your own risk!

Waterproofing

When constructing sub-earth homes and underground shelters that have shells comprised of porous materials, such as concrete or wood, make sure not to skimp on the waterproofing. There is nothing much worse than to backfill and landscape an underground shelter and then discover a leak. The only real solution is to call the backhoe or excavator back, uncover the shelter by removing the dirt, and re-do the waterproofing.

Waterproofing Concrete Shelters (information covered in book)

Waterproofing Fuel Tanks (information covered in book)

Waterproofing Culvert (information covered in book)

Waterproofing Steel Quonset Structures (information covered in book)

Backfilling (information covered in book)

Earth-Arching (information covered in book)

Compaction (information covered in book)

Landscaping Considerations (information covered in book)

Doors

Shelter entry doors and hatches have three primary requirements: airtightness, security, and heat and overpressure resistance. An airtight seal is the primary requirement of any shelter door. This can be especially difficult to achieve with a homemade blast door. Doors built to resist heat, overpressure and thwart security threats are by their nature massive and difficult to get airtight seals on. One solution is to have a primary outer door which provides heat, overpressure and security protection and a secondary inner marine door which facilitates an excellent airtight seal.

Most shelters have doors that swing open to the outside (in contrast to doors that swing inward). The reason for this is that the door is easier to build that way. In the event of an overpressure, the outside pressure pushes the door onto the door frame and the door is supported by the frame on its entire periphery. The disadvantage is that rubble resulting from a blast can prevent the door from being opened, and if the shelter doesn’t have an unblocked alternative entrance, the occupants must be freed by rescue teams coming from outside.

Doors opening to the inside allow occupants to open them even when blocked by accumulated rubble. These style doors are more difficult to construct because the overpressure is carried by dogs or pins which extend from the door into the door frame. These dogs transfer the overpressure to the door frame. Therefore, inwardly opening doors need to be small.

The best solution to being trapped inside a shelter by rubble is to have an alternative entrance/exit with a different profile, exposure and elevation. The idea here is that if one door is a horizontal surface walk-in type, then the other entrance/exit would be a vertical hatch coming up to the surface—ideally at a higher elevation. The problem of rubble blocking a vertical type hatch can be reduced by elevating the concrete reinforced hatch tube (see following pictures) several feet above the ground level, and have the hatch pivot horizontally to open, as opposed to flipping open vertically. One design that seems effective is the jack pivot type (as shown on the following page) which would allow occupants to lift the weight of any debris accumulated on top of the hatch.

Door frames for exterior entry doors should be structurally substantial. In the case of a blast shelter, the door or hatch frame should be constructed of steel reinforced concrete and have enough surface area and mass to disperse the force of overpressure into the ground. This is important because if the overpressure is not transferred to the ground, it will be transferred directly to the entry tube which will be either crushed or driven into the shelter.

Doors should be outfitted on the inside with at least two chain binder arrangements which would tightly secure the door against the effects of negative overpressure and attempts by hostile individuals to make an unauthorized entry.

Another important aspect of doors are seals. Usually these are made of rubber. Rubber burns in case of intense surface fires. Ideally, fire-resistant fiber gaskets made of kevlar (which would retain integrity at high temperatures) should be used.

To protect the door from the effects of large caliber firearms and cutting torches, steel doors should be lined internally with at least 1 inch of steel reinforced concrete.

Entry Ways (information covered in book)

Fire Suppression (information covered in book)

Sewage Disposal and Sanitation (information covered in book)

Government Regulations (information covered in book)