COMPLETELY SELF-CONTAINED PROTECTION FROM

· Structural Fiberglass Paraboloid ·Tornadoes
· Back Yard or Under Slab · Hurricanes
· Self-Contained-Fully Assembled · Forest Fires
· Chemical Toilet
· 12 v. Meridian Hydraulic Hatch System
· 12 v. Battery Bank
· 12 v. Air Supply System
· 12 v. Lighting


§ No Bugs- stainless micronic mesh is used in air inlet and outlet manifolds.
§ No Hatch Injuries- Wind can not blow the hatch cover closed to injure shelterists.
§ No Hatch Entry Problem-Wind can not prevent the hatch door from opening.
§ No Locker Room Smell- Air blower changes the air every 13 minutes
§ No Water Table Problem- Gravity ring is used for high water table.
§ No Water Leaks -fiberglass construction is water tight.
§ No Damp Dark Cavern- fiberglass is dry, white and LED light allows reading
§ No Electrical Threat if live power lines fall on shelter which is non-conductive.
§ No Emergency Escape Danger- 10,000+lbs hydraulic hatch will open under fallen debris.
§ No Building Permit Needed- shelter has no foundation and can be re-deployed elsewhere.
§ No Low Ceilings in shelter- headroom ranges from 68 to 80 inches.
§ No Corrosion -fiberglass is corrosion resistant with a 20 year warranty
§ No Negative Pressure will pull shelter hatch open or pull shelter out of the ground
§ No Flying Debris will damage air inlet or outlet manifolds
§ No External Lock to be damaged from flying debris.
§ No Imploding-the shelter is a true pressure vessel.
§ No Duration Problem –life support for 5 days, air, water, toilet, light.
§ No EMP (electromagnetic pulse) attraction or collection.

US Patents 6,438,907 B1, 63,851,919 B1, 06296693-01, other Patents Pending


SHELTER ENGINEERING DESIGN and Global Warming

As global warming continues to produce more severe weather, tornadoes and hurricanes will get more severe in intensity and duration and raise the water table in many local areas. Radius has taken this into account when designing its shelters. The earth’s atmosphere that controls the weather is extremely thin. This atmospheric layer allows the sun to warm the earth but it also allows much of the heat to be redirected back out of the atmosphere. Carbon dioxide (CO₂) from cars, factories, environmental air quality control equipment such as thermal oxidizers which produce huge amounts of CO₂ makes this atmospheric layer thicker, preventing more heat from being redirected away from the earth’s surface thereby trapping more of the heat around the earth.

There are normal global temperature fluctuations of the earth each year especially in the United States because most of the land mass of the earth is North of the equator. When the Northern land mass is tilted more toward the sun in the spring and summer the temperature is warmer and when it is tilted away from the sun in fall and winter the global temperature goes down. When the global temperature goes down, leaves fall out trees and the carbon dioxide level goes up. Global carbon dioxide levels started to be measured in 1958 and have continually risen until today are and still rising. Kilimanjaro, Africa in 1970 was snow covered but in 2000 has almost no snow. The Grinnell Glacier at Montana's Glacier National Park melted in 1998.
From ice core samples, the global temperature and carbon dioxide levels can accurately be determined for the past 650,000 years. The carbon dioxide levels parallel the global temperature for 650,000 years proving that when there is more carbon dioxide, the atmosphere traps more heat and the global temperature rises. Until recently the CO₂ level had never risen above 300 ppm (parts per million).
Hundreds of sensors in dozens of countries have measured CO₂ emissions worldwide since 2000. The CO₂ emissions are growing three times the rate observed during the 1990s, according to the National Oceanic and Atmospheric Administration (NOAA). NOAA reports that carbon dioxide levels increased by 2.4 parts per million in 2008 alone. It was hoped that the oceans would form a kind of sponge absorbing some of this global temperature increase. But such natural sponges may no longer be able to absorb atmospheric spills of CO₂ so easily, carbon project scientists reported. In the past 50 years, the researchers said, the planet's capacity to absorb the gas through soil and sea chemistry has steadily declined. The ten hottest years on record occurred in the last 14 years between 1990 and 2005.
This increase in global temperature creates more severe weather and more severe tornadoes that are larger, more intense, and more frequent now, and occur in wider geographic areas. Radius has therefore designed its shelters for longer durations than just a few minutes since shelterists may be entering the tornado shelter more frequently even within a given day or week. Re-provisioning the shelter with water, food, medical supplies, etc. may become very difficult in some areas as the severity of weather worsens. To learn more about global warming see the DVD “An Inconvenient Truth” by Al Gore for which he was awarded the Nobel Peace Prize in 2007.


Exterior dwgs.

Interior dwgs.

THE S6 Twister Resister
The S6 Twister Resister shelter is a totally self-contained 5 psi paraboloid (egg shape) underground tornado shelter designed to protect 6-10 adults for up to 3 days. It is specifically designed to operate at ground zero of an F5 tornado. The S6 includes the structural fiberglass paraboloid, fiberglass floor, 5 gallon water tank, chemical toilet, 12-volt air blower, two 130 amp hr batteries, 115 v. battery charger/controller, stainless steel screen on inlet and outlet manifolds, 12-volt LED light, Meridian Hydraulic Hatch System with remote pocket transmitter, manual hydraulic emergency escape, and gravity ring tie-down for high water tables and the negative pressure of an F5 tornado.

DESIGN
The S6 is a third generation Tornado shelter designed and developed by Walton W. McCarthy, M.E., author of PRINCIPLES of PROTECTION, U.S. Handbook of NBC Weapon Fundamentals and Shelter Engineering Standards, Fifth Edition 2002 which is the United State’s bible on shelter engineering. He is the principle engineer of Radius Engineering Inc., with over 30 years experience design­ing “high- tech” Tornado shelters. The book is dis­tributed by The American Civil Defense Associa­tion (TACDA) in Draper, UT and is known in the industry as P.O.P. The S6 was designed using CAD (computer aided drafting), CAE (computer aided engineer­ing), and FEAM (3-dimensional finite element analysis and modeling). The paraboloid shape of the S6 allows it to be a true pressure vessel for resistance to high external pressure and full height water tables. The S6 shelter system is based on 22 years field experience with McCarthy’s successful ES10 and larger sisters, P6 and P10 fiberglass underground shelters. The hatch at ground level of the S6 comes standard with an NIJ (National Institute of Justice) Class 2 hatch.

SHELTER CONSTRUCTION
The paraboloid shelter and entranceway are made of structural fiber­glass manufactured to underground storage tank standards of Underwriters Laboratory, American Society of Testing and Materials, and shelter engineering standards of PRINCIPLES of PRO­TECTION. Fiberglass was chosen as the optimum material because of its extremely high resiliency and corrosion resistance plus its ability to be shaped into a compound curved structure. The 5 psi (pounds per square inch) external pressure resistance, with no earth arching, is constant over 100 years and does not have to be de-rated each year like steel due to corrosion. Fiberglass also forms a complete vapor barrier which provides a dry atmosphere when placed below ground, and it has proven to be sound in the underground storage tank industries. In addition, one of the greatest characteristics of fiberglass is its ability to “remain intact” if overstressed. The inside of the shelter is smooth, curved, and white to create maximum brightness with minimal light. All of these facilities function without outside electricity through the use of 12-volt, deep-cycle batteries. The inside surface is easily cleaned with common detergents and is easily repaired.

SHELTER FACILITIES
The S6 contains 500 cubic feet (3,740 gal.) with headroom from 5’8” to 6’8”. This allows for almost normal living and a spacious feeling. The volume of the shelter is greater than the largest “slide in” camper that can be mounted on a full size pick-up truck. There is ample light for reading anywhere in the shelter supplied by an LED light located near the shelter ceiling. Fresh air is brought into the shelter by a 12-volt 40,000-hour 40 cfm air blower mounted to a screened air inlet manifold and designed to operate 24 hours per day for approximately 2 days for each battery. The blower supplies many times the breathing volume of air required by adults and produces a complete air change inside the shelter every 13 minutes. This system has the advantage of maintaining constant shelter temperature, constant shelter oxygen levels, constant shelter carbon dioxide levels, and constant shelter mois­ture levels, plus it prevents overheating which is common with manual air blowers in warm cli­mates. Exhausting of hot, moist, spent air is facilitated through the screened air outlet at the highest point in the shelter where it exits the shelter. This is the most efficient geometry for exhausting spent air and hydrogen gas from battery charging especially when power consumption is critical. Two 12-volt deep-cycle lead acid batteries are stored under the fiberglass floor on a fiberglass base. The normal loss of battery power is approximately 1.5% per month when the battery charger is not operating. A photovoltaic panel (solar panel) can be used to maintain the batteries if desired. A 6-amp 115 volt AC controlling battery charger is mounted in the shelter to maintain the battery charge from outside AC power. A chemical toilet is provided which has a duration with 6 adults of approximately 3 days.

Hatch Dome

The Meridian Hatch System is aerodynamically smooth . The 28 inch wide x 84 inch long manway allows very large people to simply walk into the shelter by a conventional stairway. The hatch is opened and closed from a waterproof pocket radio transmitter so there is no external lock on the hatch exterior which can be damaged from flying debris. There is also a secret way to bypass the transmitter in the event of an electrical problem. The hatch dome cover contains recessed hinges designed for severe impact of high speed flying debris. The angle of incidence of the hatch dome is only 20 degrees to allow flying debris to glance off. The hatch dome and hatch cover are designed to resist a non-shattering 3-inch diameter hail ball falling straight down at terminal velocity (87 mph) and impacting directly at a full 90-degree angle of incidence. The hatch dome is also designed to resist a non-shattering 3-inch diameter hail ball traveling horizontally at 150 mph. In addition, the hatch dome can resist a solid 2 x 4 wooden stud impacting the hatch dome like a battering ram or javelin at 300 mph depending on the hatch class. Some debris, depending on the size, shape, angle of incidence, and mass, may damage the hatch dome. This can be easily repaired with fiberglass repair kits available at marine and automotive supply stores.

MERIDIAN HATCH SYSTEM
Patents Pending

Tornado F-Scale	F0	F1	F2	F3	F4	F5
Windspeed (mph)	40-72	73-112	113-157	158-206	207-260	261-318

The hatch dome is made of a material called “Combat Composite” which is a structural fire-and bullet-resistant laminate developed by Radius Engineering Inc. It is designed to resist up to 300-mph winds and more than 8.5 on the Richter Scale. Although the hatch dome is not impenetrable, it is specifically de­signed to resist seven basic assaults from people trying to break into the shelter in compliance to P.O.P.

STORAGE AND FLOOR
The floor of the S6 is made of fiberglass and bonded to the shelter hull. There are 10 cubic feet of storage under the floor. This allows enough room to store various provisions and back-up files and photos.

SEALED
SHELTER ATMOSPHERE
When ground fires are present around the hatch, the air blower should not be turned on to bring in fresh air. During this time, the shelterists must breathe in a sealed shelter atmosphere. The safe duration time is based on a 3% carbon dioxide limit. The time it takes for the shelter atmosphere to reach this limit is a function of the number of shelterists, degree of physical activity of the shelterists, and the volume of the shelter above the floor. This duration is shown below for adults performing mild work. If the shelter is located in a double car garage that is 20 ft x 20 ft x 8 ft, the times listed in the Sealed Shelter Atmosphere graph can be increased by a factor of 6.5.

Hatch Cover –NORMAL OPERATION

The hatch cover is opened and closed by a 2.5 inch bore hydraulic cylinder located under the hatch dome and accessible from inside the entranceway. The hydraulic cylinder is powered by a 12 volt hydraulic power unit consisting of a 12 volt motor, hydraulic pump and hydraulic oil reservoir. The hydraulic power unit is located on the box beam connected to the shelter wall. The hydraulic power unit is controlled by a radio controlled button like a garage door opener. The remote transmitter will open or close the hatch cover from outside of the shelter or inside of the shelter. This 12 volt system will develop 1000 lbs of force to slide the hatch open and closed. The hatch cover can not be forced open or closed without the remote transmitter so no locking mechanism is necessary. One button on the remote transmitter opens the hatch and a second button closes the hatch which hydraulically locks in any position. The exterior of the hatch has no visual signs of a locking mechanism. This system prevents many reported injuries of people running to the shelter during high winds which pushes the hatch cover closed on top of shelterists entering the shelter. In other cases, some people may not have enough physical strength to open the shelter door during high winds.



Hatch Cover –EMERGENCY OPERATION

Should the hatch cover become blocked from debris falling on and blocking the hatch cover, the emergency escape system can be employed. Located on the 12 volt hydraulic power unit is the hydraulic hand pump. While the 12 volt hydraulic power unit is set at the factory to only a 200 psi which produces 1000 lbs of force to open the hatch cover, the hydraulic hand pump can generate 2,500 psi. At 2,500 psi, the hand pump will be able to develop over 12,000 lbs of force in the hydraulic cylinder to lift any fallen debris on top of the hatch cover.

SHIPPING AND INSTALLATION

U.S. citizens have a legal right to install a shelter. Under the second amendment of the United States Constitution, U.S. citizens are guaranteed the right to bear arms to provide protection in life threaten­ing situations. Tornadoes, earthquakes, nuclear, biological, and chemical warfare fall under this amendment as life threatening forces. A Tornado shelter falls under this classification as a defensive arm. Radius shelters do not have a foundation or running water and therefore usually do not fall under the local building codes.

EXCAVATION

The customer hires a contractor to dig a hole with a bottom dimension of 13 feet x 16 feet at a depth of 9 ft-3 inches. A three-inch layer of crushed stone is spread in the center of the floor of the hole. The top of the hole should be larger to allow for sloped walls. The excavation usually requires approximately 2 hours. A 24,000 pound excavator or larger should be used to dig the hole and lift the S6 off of the delivery truck and into the hole. If the shelter is installed in a flood zone, the shelter should be installed by berming so the hatch is one foot above the 100-year flood plain or 2 feet above storm tide surge. Berming can also be used if the shelter is installed in a location which has ledge.

INSTALLATION

The S6 can be installed in a back yard or under a garage concrete floor, the shelter must be installed before the footings are poured and installed at the proper height in relation to the concrete slab. Normally the shelter is installed on the center line of each car bay in the garage so the hatch dome is positioned between the two front tires of the car. When entering the shelter during Tornado use, the garage door should be open at least 6 inches to allow fresh air to enter the garage where both inlet and outlet air exchange.

SHELTER INSTALLATION (summary)

1. An excavator uses a 6 ft chain sling rated at least 2000 lbs vertical lifting to connect to the lifting eyes on the sides of the shelter and lifts the shelter off the truck and into the hole. The “pick height” to lift the shelter off of a single drop trailer is 15 ft.
2. The shelter is leveled at the proper height at the bottom of the hole by shoveling crushed stone under the bottom of the shelter until it is stable.
3. The fiberglass gravity ring and cables are placed around the base of the shelter.
4. The shelter is then backfilled with 40 yards of ¾ minus crushed stone or pea stone. If sand is used, it must be compacted with a “Jumping Jack”. After this stage, the surrounding soil can be used for backfill and must be compact­ed evenly around the shelter.
5. When the backfilling reaches 12 inches below ground level, the power line from the battery charger in the shelter is connected through the watertight cable connections in the shelter to the local power supply.
6. Backfill­ing continues to the original ground level. Back­filling usually requires approximately 4 hours.

HOME BUILT SHELTERS VS. COMMERCIAL SHELTERS
Advantages of purchasing a commercial underground shelter:
1) With shelters built on site, cost overruns are the rule, not the exception. Many well-intended handymen and contractors have constructed shelters which ended up running well over budget and still did not produce an operable shelter. When a shelter is built on site, you really don’t know what you will end up with. The S6 shelter allows people to deal with known costs and a proven shelter system. 2) Shelters built on site require extensive, time consum­ing, and expensive research to develop a “shelter sys­tem” capable of providing dependable life support. Even good architects or mechanical and civil engineers, do not have the expertise to develop a good dependable shelter system especially when it must function without local electricity. The S6 shelter system is based on the ES10 and P10 shelter, which has over 20 years proven field experience and complies with all P.O.P. standards. 3) Concrete shelters built on site are not able to be excavated and re-installed at another location and they are very hard to make waterproof, especially under the floor. The shortcomings of steel underground storage tanks are: a) They may require registration because its intended use is for storage of petroleum and/or chemi­cal products. b) A horizontal cylinder is a poor struc­tural shape because it behaves as flexible conduit. c) It must also be cathodically protected or fiberglass coated. d) Steel underground structures suffer from condensation on the inside walls. The S6 is designed strictly as a shelter and can be excavated and re-installed at some other location (unless it is installed under a concrete slab. 4) Shelters built on site require a building permit and confirmation by a local professional engineer because it involves actual construction, including a septic design. The S6 is a commercially available, professionally engineered Tornado shelter with a formal Operator’s Manual reviewing all operations. 5) Shelters built on site often require many days or weeks to complete construction. During this time, children are exposed to the danger of falling in the hole and curiosity seekers are afforded ample time to see what is being constructed. The S6 can be installed in one day. 6) Shelters built on site have no established market value. The S6 has a known commercial value which allows financing by banking institutions.

WARRANTY
Radius Engineering Inc. Warranties that the fiberglass parts of the S6 Tornado Shelter will not leak, corrode, or structurally fail for a period of 20 years provided that 1) the shelter is not exposed to excessive overpressure 2) The structural parts of the shelter are not modified 3) The shelter is inspected, off-loaded, assembled, backfilled and installed in accordance with the company’s installation instructions. The warranty does not apply to the parts and equipment that Radius Engineering Inc. does not manufacture. These items are covered by the individual manufacturers. Radius Engineering Inc. is continuously improving its product and therefore reserves the right to change any specification without notice. Our liability under this warranty shall be limited to, at our option, repair of the shelter, or delivery of a replacement shelter to the point of original delivery, or refund of the original purchase price. We shall not be liable for any indirect or consequential damages, labor, or installation costs.

S6 TECHNICAL DATA
Air blower life...................................................... 40,000 hours
Air blower type..................................................... 8-in dia. Reverse curve centrifugal 12-V, 7.5 watt
Air blower volume................................................ 40-60 cfm @ 1 in S.P.
Air circulation....................................................... cyclonic
Air filter................................................................ none
Air manifold......................................................... circular ring/ baffle
Armor level.......................................................... Class 2 is standard
Assembly time...................................................... 0
Backfill material required..................................... gravel or ¾- in. crushed stone (50 yards)
Batteries................................................................ 2- 130-amp hour deep cycle marine
Battery Charger..................................................... 8 amp 115 VAC Smart charger
Battery Vent......................................................... 4 inch diameter air outlet manifold.
Capacity-adults..................................................... 6 hurricane, 10 tornado
Connector port to other shelters............................ none
Duration-blower + light 24hr/day – 6 adults......... 2.5 days per battery
Emergency escape................................................ 10,000 lb hydraulic and/or manual pump
Entry Type............................................................ Fiberglass Stairs 9 inch tread, 12 inch rise
Excavated hole size.............................................. 13 ft. x 16 ft – 9’- 3” deep
Floor material....................................................... fiberglass
Floor space........................................................... 49 ft²
Fuel Tank............................................................. none
Gravity-earth........................................................ 42,178 lbs. with gravity ring
Hatch cover.......................................................... Combat Composite^TM Class 2 standard
Hatch dome –angle of incidence.......................... 20 degrees
Hatch dome material............................................. Combat Composite^TM
Hatch exterior lock............................................... hydraulic
Hatch interior latch............................................... hydraulic
Hatch pressure resistance...................................... 5 psi neg, 6000 lb neg. 6,000 lb pos
Hull material......................................................... structural fiberglass
Hydrostatic pressure (buoyancy).......................... 31,200 lbs.
Implosion type...................................................... non-catastrophic
Installation time.................................................... 1 day
Interior color......................................................... white, flame spread of 25-50 Type II, ASTM E84
Lighting................................................................ 12 volt -LED 500 lumens
Max .wind............................................................ 318 mph
Max. Headroom.................................................... 6’ - 8”
Minimum headroom............................................. 5’- 8”
Overall height....................................................... 10 ft.
Overall diameter................................................... 102 in.
Overpressure – allowable..................................... 5 psi with no earth-arching effect
Pick Height On truck............................................ 15 ft with 6 ft sling
Protection Factor Gamma..................................... 0
Protection Factor Neutron..................................... 0
Sealed shelter atmosphere- 6 adults...................... 3 hours
Septic System....................................................... chemical toilet
Shape tolerance................................................... +/- 0.1 inches
Shape.................................................................... paraboloid 1:1.24 elliptical ratio
Shelter Rating-...................................................... Tornado, hurricane
Shipping weight.................................................... 2500 lbs.
Storage volume-under floor.................................. 10 ft³
Thru hull couplings............................................... 2- ¾- inch NPTF standard
Thru hull hookups................................................ outside 110-volt, antenna cables, solar, etc.
Volume-Total....................................................... 500 ft³ (3,553 gal.)
Water table allowable height................................. full water table to ground surface
Water Tank........................................................... 5 gallons


[1] PRINCIPLES OF PROTECTION, The US Handbook Of NBC Weapon Fundamentals and Shelter Engineering Standards, Fifth Edition, 2002.