|
COMPLETELY SELF-CONTAINED PROTECTION
FROM
·Structural Fiberglass Paraboloid ·Tornadoes
·MCAS Air Filtration System ·Nuclear Weapons
·Toilet, Shower and Septic System ·Chemical Weapons/Accidents
·Battery Operated ·Nuclear Power Plant Accidents
·Decontamination ·Nuclear/Chemical Terrorism
·Communications System ·Power Plant Failures
·Lighting ·Forest Fires and Famines

THE P15 DISASTER SHELTER
The P15 is a totally self-contained 40-150 psi paraboloid (egg
shape) underground disaster shelter designed to protect 15 adults for long
periods or 25 people for short durations such as during tornadoes. The product
was specifically designed and developed to protect people during and after
disasters such as tornadoes, hurricanes, earthquakes, storms, forest fires,
power failures, nuclear power plant accidents, nuclear/chemical terrorism, and
full-scale protracted nuclear, chemical and biological war. A tremendous
effort has been made to think of every conceivable incident that shelterists
could face in the P15 shelter. Many geometrical shapes were experimented with
before finalizing the P15. The P15 includes the fiberglass paraboloid
structure, fiberglass entranceway, fiberglass/composite hatch, MCAS air filter,
125 gallon fiberglass septic tank, 1000 gallon internal water tank, fiberglass
floor, fiberglass counter, fiberglass shower wall, fiberglass battery housing,
toilet, floor, twenty-four 12- volt deep cycle batteries, gray water tank, all
wiring, all plumbing, etc. The P15 requires approximately 1 man-hour to
connect the entranceway to the shelter.
DESIGN
The P15 is a third generation disaster 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 chief engineer of RADIUS ENGINEERING INC., with over 29 years
experience designing “high- tech” disaster 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 P15 was designed using CAD (computer aided
drafting), CAE (computer aided engineering), and FEAM (3-dimensional finite
element analysis and modeling). A shelterist in the P15 under heavy, direct effects
from two 1-MT nuclear weapons, has at least the same probability of survival
(99.7%) as a person living and working in peacetime. The paraboloid shape of
the P15 allows it to be a true pressure vessel for resistance to high external
pressure. The P15 shelter system is a third generation design and is based on
14 years field experience with McCarthy’s successful P10 fiberglass underground
shelter. The P15 is much easier to enter and exit with its offset
entranceway. The hatch at ground level of the P15 is available in several
different levels of threat resistance. The geometry of the P15 allows the
much-preferred offset entranceway. This has the same radiation geometry
shielding as a 90-degree entranceway plus it provides the most efficient escape
for moisture and heat.
SHELTER CONSTRUCTION
The paraboloid shelter and entranceway are made of structural
fiberglass manufactured to The 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 compoundly curved
structure. The 40 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 like steel each passing year 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.
LEACHING SEPTIC TANK
Opposite the two MCAS Air Filters is the 125-gallon fiberglass
leaching septic tank designed into the entranceway. The septic tank has duration
of 3-6 months depending on the number of shelterists and diet. It is pumped
out with an optional manual septic pump from the ground surface by removing the
septic tank access port.
SHELTER FACILITIES
The P15 contains 2253 cubic feet (16,854gal) with headroom from 7’-4”
to 9’-4”. This allows normal living and a very spacious feeling. There is
ample light for reading anywhere in the shelter supplied by a two 6 element
LED white lights located on the shower wall to provide bounced lighting off the
ceiling. Fresh filtered air is brought into the shelter by a 12-volt
40,000-hour air blower designed to operate 24 hours per day for approximately
30 days and supplies many times the breathing volume of air required by
adults. 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 entranceway which is located on the
end of the shelter but very close to the highest point of the ceiling. The
hot, moist, spent air rises up through the entranceway to the vent at the top
of the entranceway where it exits the shelter through the hatch dome at ground
level. This is the most efficient geometry for exhausting spent air,
especially when resisting intruder assaults is a critical part of the hatch
design.
BATTERY
POWER
Twenty-four 115 AH 12-volt deep-cycle sealed batteries are stored
in a fiberglass battery box molded into the fiberglass floor. The normal loss
of battery power is approximately 1.5% per month without any charging.

A 115 volt battery charger/maintainer and timer is used to keep
the batteries charged. A photovoltaic panel (solar panel) can also be used to
maintain the batteries if desired. A 50-foot battery charging cable can also
be connected from the batteries in the shelter to the battery in a car to allow
the car alternator to charge the batteries.
12 VOLT POWER CONSUMPTION
|
Electrical Load
|
Watts/hr
|
Hour/Day
|
Days
|
Total Watts Used
|
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Air Blower (2)
|
16
|
24
|
30
|
11,520
|
|
Light
|
15
|
16
|
30
|
7,200
|
|
Water Pump
|
72
|
42 hrs/1000 gal
|
-----
|
3,096
|
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Scanner
|
6
|
4
|
30
|
720
|
|
HAM-Receive*
|
12
|
1
|
30
|
360
|
|
HAM Transmit
|
120
|
1
|
6
|
720
|
|
UV Light
|
35
|
24
|
2
|
1,680
|
|
Hydraulic Power Unit
Opening hatch 1 cycle (10
sec)
|
746
( 1 HP)
|
1 min
|
---
|
12
|
|
Total Power Consumption
|
|
|
|
25,632
|
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Total Power Available 80%
|
|
|
|
26,496
|
*The scanner and Ham radio
would not normally be used at the same time.
AIR FILTRATION
1. Contaminated air enters the air intake
hole on the elliptical hatch dome. It then travels around under the hatch dome
where the air velocity slows allowing rain and heavy particles to fall out.
2. Contaminated air then travels into the
vertical pipe under the hatch dome and past the ball valve.
3. The contaminated air then travels into the
stainless steel micronic washable screen/pre-filter removing more of the heavier particles.

4.
The air then
travels into the Gas Agent Test Housing where the air can be tested using the
M256A chemical agent test kit. A 4 inch white pipe plug is removed to insert
the test kit.

HEPA/Filter
Sleeve
5.
The contaminated air
then travels into the core of the HEPA/Carbon filter designed to remove 99.99%
of particles that are 0.3 u (microns) and larger. This is where the carriers of
biological warfare agents are removed. The photo at left shows the HEPA/Carbon
sleeve.
6.
The air then travels
into the activated carbon layer to remove the radioactive iodine gas.
7.
The next layer is made
of Whetlerite/TEDA carbon to remove any chemical warfare agents.
Ultraviolet Bulb Over View Port

8.
The air then passes
through a filter fabric to remove any carbon fines.
9.
The last stage of
filtration after the filter sleeve is the ultraviolet light chamber were
viruses and bacteria are exposed to more than 11,000 microwatts seconds/cm2
killing all airborne viruses and bacteria.
10.
The filtered air then
enters the air blower centrifugal reverse curve motorized impeller and into the
shelter.
11.
As the air blower
pumps filtered air into the shelter, the shelter is slightly pressurized. This
positive pressure plus the heat generated in the shelter from body heat,
cooking, and showering, forces the spent air to the highest point in shelter
near the top of the entranceway.
12.
At the top of the
entranceway is the air outlet screen where the spent air passes through and up
the air pipe and out of the elliptical hatch dome air outlet hole. Some air
will pass through and around the hatch cover base because the hatch cover is
not intended to be air-tight.
13.
As the air passes around
the underside of the hatch dome is equilibrates with the outside air. This
results in little or no thermal signature because there is little difference
between the spent air and ambient air.
Air Outlet
The spent air containing carbon dioxide, heat, moisture,
and odors exits the shelter at the highest point just under the hatch dome.
The air outlet housing contains a stainless steel micronic screen to prevent
bees and even tiny ants from entering the shelter. The air outlet housing can
be closed by inserting a 4 inch diameter plastic pipe plug.
The P15 Owner’s Manual details specific safe
procedures for replacing contaminated HEPA filters. Both air inlet and air
outlet have shut-off valves and washable stainless micronic screens accessible
from inside the shelter.
SEISMIC JOINT
This triple axis seismic joint allows the entranceway free and
independent movement from the main shelter. The entranceway is located within
the frost line, while the shelter is well below the frost line. This creates
tremendous stresses during winter months when the entranceway is forced up 0.5
- 1.25 inches due to frozen ground. The seismic joint removes these stresses
by allowing vertical movement of the entranceway and also allows the top of the
entranceway to move laterally to maintain structural integrity during rolling
ground motion from severe ground shock. The entranceway can also move in
translation or sideways 1 inch.
STORAGE
There are 37 cubic feet of storage (276 gal.) under the floor.
In addition there are 300 cubic feet of storage under the upper deck that allow
forty-four – 5-gallon food tanks to fit under the upper deck. A 30-gallon
aluminum alcohol tank is used for cooking. The 5 gallon food tanks are used to
store grain, powdered milk, salt, sugar, beans, TVP, honey, etc. and hold approximately 2000 lbs. of food, forming a 1 year food supply for five people. The food
supply can be extended with the purchase of more food tanks. The material and
thickness of these food tanks allows the much preferred carbon dioxide packing
of food as opposed to the nitrogen packing of food. The 30-gallon aluminum
methanol tank was sized to boil all the water in the 1000-gallon water tank
plus all the food in 44 of the 5-gallon food tanks. Storage is more easily
managed with the optional Moon Shelves which runs around the perimeter
of the shelter and provide an additional 13 ft3.
WATER
STORAGE
The P15’s
1000 gallon fiberglass tank is located under the floor. The tank can be
accessed by a manway on the shelter floor. The volume in the tank is
determined by a dip stick in the center of the floor which is used in
conjunction with the graph below. The water tank is filled by placing a garden
hose into the manway and filling the tank and adding hypochlorite during
filling. The water tank is emptied each year by turning the 3-way valve to change
the flow to the outlet port where a garden house is used to transfer the water
up to the ground surface.

MULTIPLE SHELTERS
Multiple P15’s can be connected together using “T connectors” and
seismic joints. This is usually limited to 10 shelters.
HATCH
DOME


The elliptical hatch dome at ground level is
aerodynamically smooth. The 24 x 26 -inch manhole allows very large people
with a 75-inch+ waist to enter the shelter quickly. The hatch dome contains the
recessed hatch cover that slides open and is designed for severe impact of high
speed flying debris. The angle of incidence of the hatch dome is only 30
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 30 to 350 mph depending on the hatch class. Some debris,
depending on the size, shape, angle of incidence, and mass, may cosmetically
damage the hatch dome. This can be easily repaired with fiberglass repair kits
available at marine and automotive supply stores.
|
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
CompositeTM” which is a
structural fire-and bullet-resistant laminate developed by Radius Engineering
Inc. The hatch dome is also designed to protect the shelter from a fire reaching
1700oF for one hour while maintaining its structural
integrity in compliance to ASTM E119. This design and material makes the P15
very stealthy. It produces little or no thermal signature, little or no
metallic signature, and little or no radar signature. When the shelter is
installed, all that can be seen is the dark army-green hatch dome at ground
level. This makes it almost impossible to be detected by modern target
acquisition equipment. It is designed to resist 350-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.
The hatch dome and hatch cover are manufactured
according to The National Institute of Justice NIJ standards from Class 0
(standard on P15) up to Class IV to resist penetration by various threats. The
material and thickness vary as the threat level increases. The classes listed
below are based on resisting 90% of all of the bullet types at various
velocities listed known as (V-90). The barrel length, feet per second (fps)
or meters per second (mps) for the test are noted.
|
NIJ
Threat
Level
|
Hatch
Material
(V-90)
|
Threat/Bullet
Type
|
Barrel
Length
(inches)
|
fps
|
mps
|
|
Class
0
|
Structural
Fiberglass-self-extinguishing (standard)
|
Light
Hammer and hatchet assaults, 3 in. dia. Hail @ 87-mph vertical, 150-mph
horizontal
2
x 4 stud @ 30-mph
|
NA
|
NA
|
NA
|
|
Class
I
|
Combat
Composite
self-extinguishing
|
.22 Cal. 40 Gr. LR
.25 Cal Auto 71 Gr. FMJ
.32 Cal. Auto 71 Gr. FMJ
.380
Cal. Auto 88 Gr. JHP
.38
Cal Special Lead 158 Gr. RN
.38
Cal Special 158 Gr. SWC
2
x 4 stud @ 70-mph
|
6
2
4
4
6
6
--
|
1050
810
905
990
850
850
|
320
247
276
302
259
259
|
|
Class
II
|
Combat
Composite
self-extinguishing
|
.41
Mag. 210 Gr. JSP
.44
Mag. 240 Gr. JSP
.44
Mag. 240 Gr. Lead SWC
.357
Mag. 125 Gr. JHP
.357
Mag. 110 Gr. JHP
.357
Mag. 158 Gr. JSP
.357
Mag. 158 Gr. Hornady
19mm
175 Gr. Silvertip
9mm 124 Gr. FMJ
9mm 115 Gr. Silvertip
2
x4 stud @ 100-mph
|
4
4
4
4
4
6
6
5
5
5
--
|
1300
1180
1200
1450
1550
1395
1445
1225
1175
1170
|
397
360
366
442
473
425
441
372
358
355
|
Class III
|
Combat Composite
self-extinguishing
|
7.62
NATO Ball 150 Gr. M-80 steel Jack
7.62
NATO Ball 150 Gr. m-80 FMJ
30.06
PSP 180 Gr.
.30
Carbine 110 Gr. FMJ
12-Gauge
Rifled Slug
.223
(5.56mm) 55 Gr. FMC
7.62
x 39 Ball
2
x4 stud @ 200-mph
|
28
28
24
18
18
20
22
22
22
--
|
2750
2750
2750
1950
1550
3075
2400
|
838
838
824
595
473
938
732
|
|
Class
IV
|
Combat
Composite
self-extinguishing
|
30.06
A.P. M-2
7.62
mm NATO A.P. 308 Win
SS
109 FN NATO .223 (5.56mm)
7.62
x 39 Russian/Chinese A.P.I.
2
x4 stud @ 350-mph
|
26
24
20
22
--
|
2850
2750
3090
2550
|
868
838
942
778
|
Hatch Cover interior and
Exterior Lock
The P15 hatch slides open and closed hydraulically powered by a 12 volt hydraulic power unit located on the moon shelf in the
shelter. The hatch slides and locks wherever it stops. The remote radio
controlled transmitter has a button to slide the hatch closed and open. When
inside the shelter, the hatch can be closed by standing on the floor and
activating the transmitter. This allows submarine type entry without human power
to move the 200 lb hatch cover. The hatch cover is recessed in the hatch dome
and protected from flying debris for 320 degrees. The hatch cover is designed
to resist 5300 lbs. of uplifting force caused by the negative pressure of a
tornado or explosion and 42,080 lbs of overpressure. The average time it takes
for untrained or inexperienced people to enter the shelter is approximately
8-10 seconds per person.
SHELTER DEFENSE
The
P15 is not impenetrable but is difficult to break into while shelterists are
inside.
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INTRUDER
ASSAULT
|
P15
RESISTANCE
|
|
1.
Intruder trying to break into
hatch using sledgehammer, hatchets, and guns.
|
Class
0 Hatch resists light hammer and hatchet assaults
Class
I -IV Hatch resists all assaults
|
|
2.
Intruder trying to clog the air
intake/outlet to suffocate the shelterists thus forcing them outside.
|
Shelterists
can open up hatch and reach over to unclog air intake or wait in safety in
the shelter for many hours in sealed shelter atmosphere while the intruder is
exposed to the outside danger.
|
|
3.
Intruder trying to suffocate
shelterists by creating fire on top of the hatch thus forcing the shelterists
outside.
|
All
classes of the hatch are resistant to fire and the shelterists can breath
normally inside the shelter based on sealed shelter atmosphere.
|
|
4.
An intruder trying to run over
the shelter or hatch with an automobile or truck.
|
If
this vehicle becomes a threat, the Emergency Acme Jack rod can be used.
|
|
5.
An intruder trying to drown
shelterists by forcing water into the air inlet/out.
|
The
air inlet on the hatch dome are baffled to prevent this type of assault.
|
|
6.
An intruder trying to attach rope
onto the hatch or air manifolds to damage or pull out of ground.
|
The
hatch dome is a smooth design with no projections to easily attach to.
|
- An
intruder using a cutting torch to cut the hatch open.
|
The
hatch is impervious to a cutting torch.
|
|
All
attacks above
|
Release
of tear gas through hatch. Details are reviewed in Owner’s Manual.
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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.
OVERPRESSURE
CHOKING
The P15 does not use blast
valves. Instead, it uses the “overpressure choking” which has no moving parts.
The inlet air valve and outlet air valve are sized to prevent excessive
pressure from developing inside the shelter. This is a combination of what is
known as the Ideal Gas Law combined with Bernoulli's Law. These two theories
combined state that two volumes of air (outside air volume and shelter air
volume) with differing pressure will reach equilibrium or
"equilibrate" over a period of time. This period of time depends on
the level of overpressure, volume of the shelter, diameter and length of the
air inlet and outlet pipe, resistance of air filter, and duration of the
overpressure which is very short and constantly decreasing. Simply stated; the
air inlet and outlet are sized so that there is not enough time for the two
volumes of air to equilibrate. The outside pressure at maximum duration is
simply not able to equilibrate through a 3-inch diameter air inlet and outlet
within the overpressure duration.
PLUMBING SYSTEM
The water supply
system is based on a 12-volt high pressure automatically regulated water pump
and stainless steel pressure tank to maintain system pressure. The pump
produces enough pressure to force the water through the 0.3 micron absolute
ceramic water filter and supplies approximately 0.5 gallons per minute at the
sink faucet and shower head in the bathroom. Two of the fourteen batteries will
supply enough power to pump 1000 gallons of filtered water to the shelter. The fiberglass counter contains a stainless steel sink where
dishes and clothes are washed. The sink d
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