U.S. patent application number 13/232680 was filed with the patent office on 2012-01-05 for biological home defense system.
Invention is credited to Stanley L. Wiener.
Application Number | 20120003919 13/232680 |
Document ID | / |
Family ID | 37892306 |
Filed Date | 2012-01-05 |
United States Patent
Application |
20120003919 |
Kind Code |
A1 |
Wiener; Stanley L. |
January 5, 2012 |
Biological Home Defense System
Abstract
The invention relates to biological home defense systems for use
by populations at risk of widespread biological attack via
biological weapons of mass destruction, especially biological
weapons involving aerosol attacks. The present invention is also
related to methods for using such biological home defense systems
wherein meteorological data is used to issue advisories with regard
to the use of such biological home defense systems to a population
at risk of exposure to biological weapons of mass destruction.
Inventors: |
Wiener; Stanley L.;
(Naperville, IL) |
Family ID: |
37892306 |
Appl. No.: |
13/232680 |
Filed: |
September 14, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12684011 |
Jan 7, 2010 |
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13232680 |
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Current U.S.
Class: |
454/338 |
Current CPC
Class: |
B01D 2257/91 20130101;
B01D 2258/0225 20130101; B01D 46/0091 20130101; B01D 2273/30
20130101; B01D 46/10 20130101; B01D 46/446 20130101 |
Class at
Publication: |
454/338 |
International
Class: |
F24F 7/06 20060101
F24F007/06 |
Claims
1. A biological home defense system for use in existing or new
construction dwelling structures, said system comprising: (1) a
variable speed blower motor to draw air into a safe room from an
adjacent room through a duct passing though a common wall between
the safe room and the adjacent room; (2) at least one filtering
element in communication with the blower motor, whereby air from
the adjacent room passes through the filtering element and then
into the safe room, wherein the filtering element can remove
biological agent particles greater than about 0.3 microns in
diameter from the air; (3) a pressure sensing device whereby air
pressures within the safe room and the adjacent room can be
monitored; (4) a carbon dioxide sensing device wherein the carbon
dioxide levels in the safe room can be monitored; and (5) an
exhaust or removal system by which the carbon dioxide level in the
safe room can maintained below a preset carbon dioxide value; and
(6) a control system; wherein the control system uses air pressure
data to control the variable speed blower motor in order to
maintain a positive air pressure within the safe room above a
preset pressure value; wherein the control system uses the carbon
dioxide level data to operate the exhaust or removal system as
needed in order to maintain the carbon dioxide level within the
safe room below the preset carbon dioxide value; and wherein the
safe room is sealed sufficiently to allow the variable speed blower
motor to operate at a speed whereby the air passing through the
filtering element is efficiently filtered, while maintaining the
positive air pressure above the preset pressure value.
2. The biological home defense system as defined in claim 1,
wherein the safe room is sealed using an epoxy paint to coat the
walls, ceiling, and floor of the safe room.
3. The biological home defense system as defined in claim 1,
wherein the filtering element is a HEPA filter, a filter containing
an electrostatic material, or a combination HEPA and electrostatic
material filter.
4. The biological home defense system as defined in claim 2,
wherein the filtering element is a HEPA filter, a filter containing
an electrostatic material, or a combination HEPA and electrostatic
material filter.
5. The biological home defense system as defined in claim 3,
further comprising a chemical filter through which air can pass to
provide further protection in the case of a chemical attack.
6. The biological home defense system as defined in claim 4,
further comprising a chemical filter through which air can pass to
provide further protection in the case of a chemical attack.
7. A method for protecting a population at risk of exposure to
biological weapons of mass destruction containing biological
agents, said method comprising: (1) making biological home defense
systems and instructions for their use during a biological warfare
attack available to the population; (2) monitoring for biological
warfare attack; (3) in the event of attack or during periods of
high risk of attack, evaluating current and predicted weather
patterns in the geographic areas within, adjacent to, and downwind
of, the biological warfare attack to determine likely distribution
of significant amounts of the biological agents within the
geographic areas; (4) alerting the population and directing the use
of the biological home defense systems within the geographic areas
of likely distribution of the biological agents; (5) reevaluating,
based on current and predicted weather patterns and data regarding
actual distribution of the biological agents within the geographic
areas, updated likely distribution of significant amounts of the
biological agents within the geographic areas over time to provide
updates; (6) reporting the updates to the population with, as
appropriate, instructions for continued use or termination of the
use of the biological home defense systems within the geographic
areas of updated likely distribution of the biological agents or
within new geographic areas of updated likely distribution of the
biological agents; and (7) repeating steps (5) and (6) until no
significant risk of exposure remains; wherein the biological home
defense systems comprise (1) a variable speed blower motor to draw
air into a safe room from an adjacent room through a duct passing
though a common wall between the safe room and the adjacent room;
(2) at least one filtering element in communication with the blower
motor, whereby air from the adjacent room passes through the
filtering element and then into the safe room, wherein the
filtering element can remove biological agent particles greater
than about 0.3 microns in diameter from the air; (3) a pressure
sensing device whereby air pressures within the safe room and the
adjacent room can be monitored; (4) a carbon dioxide sensing device
wherein the carbon dioxide levels in the safe room can be
monitored; (5) an exhaust or removal system by which the carbon
dioxide level in the safe room can maintained below a preset carbon
dioxide value; and (6) a control system; wherein the control system
uses air pressure data to control the variable speed blower motor
in order to maintain a positive air pressure within the safe room
above a preset pressure value; wherein the control system uses the
carbon dioxide level data to operate the exhaust or removal system
as needed in order to maintain the carbon dioxide level within the
safe room below the preset carbon dioxide value; and wherein the
safe room is sealed sufficiently to allow the variable speed blower
motor to operate at a speed whereby the air passing through the
filtering element is efficiently filtered, while maintaining the
positive air pressure above the preset pressure value.
8. The method as defined in claim 7, wherein the safe room is
sealed using an epoxy paint to coat the walls, ceiling, and floor
of the safe room.
9. The method as defined in claim 7, wherein the filtering element
is a HEPA filter, a filter containing an electrostatic material, or
a combination HEPA and electrostatic material filter.
10. The method as defined in claim 8 wherein the filtering element
is a HEPA filter, a filter containing an electrostatic material, or
a combination HEPA and electrostatic material filter.
11. The method as defined in claim 9, wherein the biological home
defense systems further comprise a chemical filter through which
air can pass to provide further protection in the case of a
chemical attack.
12. The method as defined in claim 10, wherein the biological home
defense systems further comprise a chemical filter through which
air can pass to provide further protection in the case of a
chemical attack.
13. A safe room system for use in existing or new construction
structures for individuals with severe respiratory conditions, said
system comprising: (1) a variable speed blower motor to draw air
into a safe room from an adjacent room through a duct passing
though a common wall between the safe room and the adjacent room;
(2) at least one filtering element in communication with the blower
motor, whereby air from the adjacent room passes through the
filtering element and then into the safe room, wherein the
filtering element can remove biological agent particles greater
than about 0.3 microns in diameter from the air; (3) a pressure
sensing device whereby air pressures within the safe room and the
adjacent room can be monitored; and (4) a control system; wherein
the control system uses air pressure data to control the variable
speed blower motor in order to maintain a positive air pressure
within the safe room above a preset pressure value; and wherein the
safe room is sealed sufficiently to allow the variable speed blower
motor to operate at a speed whereby the air passing through the
filtering element is efficiently filtered, while maintaining the
positive air pressure above the preset pressure value.
14. An isolation room system for use in existing or new
construction structures, said system comprising: (1) a variable
speed blower motor to draw air from an isolation room and vent it
outside the structure via a duct passing though a common wall
between the isolation room and the outside; (2) at least one
filtering element in communication with the blower motor, whereby
air from the isolation room passes through the filtering element
and then to the outside, wherein the filtering element can remove
biological agent particles greater than about 0.3 microns in
diameter from the air; and (3) a pressure sensing device whereby
air pressures within the isolation room and the outside and other
rooms in the structure can be monitored; and (4) a control system;
wherein the control system uses air pressure data to control the
variable speed blower motor in order to maintain a negative air
pressure within the isolation room relative to outside and other
rooms in the structure at a preset pressure value; and wherein the
safe room is sealed sufficiently to allow the variable speed blower
motor to operate at a speed whereby the air passing through the
filtering element is efficiently filtered, while maintaining the
negative air pressure at the preset pressure value.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a Continuation of application Ser. No.
12/684,011, filed Jan. 7, 2010, which claims the benefit of U.S.
Provisional Application No. 60/632,314, filed Dec. 1, 2004, which
is incorporated by reference in its entirety herein.
FIELD OF THE INVENTION
[0002] The invention relates to biological home defense systems for
use by populations at risk of widespread biological attack via
biological weapons of mass destruction, especially biological
weapons involving aerosol attacks. The present invention is also
related to methods for using such biological home defense systems
wherein meteorological data is used to issue advisories with regard
to the use of such biological home defense systems to a population
at risk of exposure to biological weapons of mass destruction.
BACKGROUND OF THE INVENTION
[0003] The tragic events of Sep. 11, 2001, and the anthrax exposure
cases thereafter clearly demonstrated the risks of terrorist
attacks on civilian populations anywhere in the world using weapons
of mass destruction. Biological weapons pose a significant threat
to such civilian populations. Although the anthrax exposure shortly
after September 11 appears to be almost exclusively through contact
with contaminated mail, these events highlight the potential risk
from such biological agents. A likely mode of delivery of highly
infectious or toxic agents is by atmospheric release since
potentially large populations could be exposed in a relatively
short time. Aerosol particles in the range of about 0.3 to about 15
microns in diameter could be delivered by rockets, bomblets with
aerosol nozzles, missiles, aircraft equipped with tanks and spray
nozzles (e.g., crop dusting aircraft, helicopters, and the like),
small boats, trucks, or cars equipped with aerosol generators or
from multiple fixed sites in a population-dense area. Delivery to
sites 1 to 50 km upwind of large populations centers (e.g., the
population corridor extending along the east coast from Washington,
D.C., to Boston), could be devastating.
[0004] Aerosol or biological agents, when weaponized, may consists
of one or more pathogenic species and are usually at much higher
concentrations when entering unprotected human airways than when
such pathogens are involved in natural epidemics of the diseases
they cause. Such attacks are predicted to cause a severe spectrum
of diseases with unusually high morality rates. To prevent wide
spread casualties from an aerosol attack, it is imperative that
access of aerosol particles to the airway and conjunctivae of
potential victims be markedly minimized.
[0005] Gas-type masks potentially offer at least initial protection
from such aerosol bioattacks. To be effective, however, the masks
must, in addition to filtering out or otherwise removing the
biological agent, should be readily available, inexpensive, easy to
use by essentially untrained personnel, present relatively small
pressure gradients during breathing, easy to adapt to personnel of
varying ages and/or sizes, lightweight, and comfortable to wear for
prolonged periods of time (including periods of sleep). We recently
described biological defense masks having the desired
characteristics for general civilian population use in U.S. patent
application Ser. No. 10/316,474, filed on Dec. 12, 2002, which is
hereby incorporated by reference.
[0006] Bioshield, a $5.6 billion program was signed into law on
Jul. 21, 2004, by President Bush. This program is designed to help
the government buy and deploy defenses against catastrophic attacks
with biological agents. The plan is to provide for purchase of
smallpox vaccine and a new anthrax vaccine. Terrorists can defeat
this approach this by not using these specific agents. Purchase and
stockpiling of antibiotics is also a futile defense since
terrorists can use antibiotic resistant agents. In brief a medical
treatment defense, when there are high numbers of bioweapon
casualties, is at best a salvage operation and not likely to reduce
deaths by more than a few percent. The use of rapid responders,
stockpiled antibiotics, emergency rooms with added beds and/or
isolation rooms, and initiation of vaccinations after a major
attack provides only limited protection against massive aerosol
release of biological agents of mass destruction. These agents can
be easily imported in baggage or large containers into the US and
may already be hidden somewhere within our borders. Single cities
may be attacked at variable intervals or multiple cities in a
period of a few days. The task of immunizing millions of exposed
persons, or distributing drugs that may not be effective or cause
severe side effects adds to the futility of such an approach. Once
there is a mass outbreak of one or more infectious diseases it is
certain that the medical system of any large city will be
overwhelmed.
[0007] Biological defense masks can provide important initial
protection for the general population in the event of an attack
with weapons of mass destruction. Medical treatment options can
provide limited protection for specific biological agents. There
remains a need for a longer term, more substantial and more general
means of protection for the general population, especially one
which can easily and inexpensively incorporated into dwelling units
or structures, including existing energy-non-efficient and/or
energy-efficient structures as well as new construction. Moreover,
there is a need for methods employing such biological defense
systems in combination with meteorological data whereby advisories
can be issued with regard to the use of such biological defense
systems to a population at risk of exposure to biological weapons
of mass destruction. The present invention provides such biological
defense systems and methods for using them.
SUMMARY OF THE INVENTION
[0008] The invention relates to biological home defense systems for
use by populations at risk of widespread biological attack via
biological weapons of mass destruction, especially biological
weapons involving aerosol attacks. The present invention is also
related to methods for using such biological home defense systems
wherein meteorological data is used to issue advisories with regard
to the beginning and/or termination of use of such biological home
defense systems to a population at risk of exposure to biological
weapons of mass destruction.
[0009] The present invention provides a biological home defense
system for use in existing or new construction dwelling structures,
said system comprising (1) a variable speed blower motor to draw
air into a safe room from an adjacent room through a duct passing
though a common wall between the safe room and the adjacent room;
(2) at least one filtering element in communication with the blower
motor, whereby air from the adjacent room passes through the
filtering element and then into the safe room, wherein the
filtering element can remove biological agent particles greater
than about 0.3 microns in diameter from the air; (3) a pressure
sensing device whereby air pressures within the safe room and the
adjacent room can be monitored; (4) a carbon dioxide sensing device
wherein the carbon dioxide levels in the safe room can be
monitored; (5) an exhaust or removal system by which the carbon
dioxide level in the safe room can maintained below a preset carbon
dioxide value; and (6) a control system; wherein the control system
uses air pressure data to control the variable speed blower motor
in order to maintain a positive air pressure within the safe room
above a preset pressure value; wherein the control system uses the
carbon dioxide level data to operate the exhaust or removal system
as needed in order to maintain the carbon dioxide level within the
safe room below the preset carbon dioxide value; and wherein the
safe room is sealed sufficiently to allow the variable speed blower
motor to operate at a speed whereby the air passing through the
filtering element is efficiently filtered, while maintaining the
positive air pressure above the preset pressure value.
[0010] This invention also provides a method for protecting a
population at risk of exposure to biological weapons of mass
destruction containing biological agents, said method
comprising:
[0011] (1) making biological home defense systems and instructions
for their use during a biological warfare attack available to the
population;
[0012] (2) monitoring for biological warfare attack;
[0013] (3) in the event of attack or during periods of high risk of
attack, evaluating current and predicted weather patterns in the
geographic areas within, adjacent to, and downwind of, the
biological warfare attack to determine likely distribution of
significant amounts of the biological agents within the geographic
areas;
[0014] (4) alerting the population and directing the use of the
biological home defense systems within the geographic areas of
likely distribution of the biological agents;
[0015] (5) reevaluating, based on current and predicted weather
patterns and data regarding actual distribution of the biological
agents within the geographic areas, updated likely distribution of
significant amounts of the biological agents within the geographic
areas over time to provide updates;
[0016] (6) reporting the updates to the population with, as
appropriate, instructions for continued use or termination of the
use of the biological home defense systems within the geographic
areas of updated likely distribution of the biological agents or
within new geographic areas of updated likely distribution of the
biological agents; and
[0017] repeating steps (5) and (6) until no significant risk of
exposure remains;
[0018] wherein the biological defense systems comprise said system
comprising (1) a variable speed blower motor to draw air into a
safe room from an adjacent room through a duct passing though a
common wall between the safe room and the adjacent room; (2) at
least one filtering element in communication with the blower motor,
whereby air from the adjacent room passes through the filtering
element and then into the safe room, wherein the filtering element
can remove biological agent particles greater than about 0.3
microns in diameter from the air; (3) a pressure sensing device
whereby air pressures within the safe room and the adjacent room
can be monitored; (4) a carbon dioxide sensing device wherein the
carbon dioxide levels in the safe room can be monitored; (5) an
exhaust or removal system by which the carbon dioxide level in the
safe room can maintained below a preset carbon dioxide value; and
(6) a control system;
[0019] wherein the control system uses air pressure data to control
the variable speed blower motor in order to maintain a positive air
pressure within the safe room above a preset pressure value;
wherein the control system uses the carbon dioxide level data to
operate the exhaust or removal system as needed in order to
maintain the carbon dioxide level within the safe room below the
preset carbon dioxide value; and wherein the safe room is sealed
sufficiently to allow the variable speed blower motor to operate at
a speed whereby the air passing through the filtering element is
efficiently filtered, while maintaining the positive air pressure
above the preset pressure value.
[0020] Although this invention is mainly intended as a protection
measure against biological weapons of mass destruction containing
biological agents, it may also be used for other proposes. Thus,
for example, the present invention could also to create safe rooms
to benefit individuals with severe asthma, severe upper airway
allergies, and/or similar debilitating or life threatening
respiratory conditions. This invention may also be used to create
isolation rooms in the home and/or in non-public or public
buildings (e.g., hospitals, nursing homes, and the like); the
ability to quickly and inexpensively create such isolation rooms
could be especially useful, for example, in case of an influenza
pandemic.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 illustrates one embodiment of the biological home
defense system of this invention used to install a safe room.
[0022] FIG. 2A illustrates a flowchart for a controller of the
biological home defense system of FIG. 1 under normal operating
conditions.
[0023] FIG. 2B illustrates a flowchart for a controller of the
biological home defense system of FIG. 1 to maintain CO.sub.2
levels in desirable range in the safe room.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] The invention relates to biological home defense systems for
use by populations at risk of widespread biological attack via
biological weapons of mass destruction, especially biological
weapons involving aerosol attacks. The present invention is also
related to methods for using such biological home defense systems
wherein meteorological data is used to issue advisories with regard
to the use of such biological home defense systems to a population
at risk of exposure to biological weapons of mass destruction.
[0025] The present invention uses a relatively small blower motor
that draws filtered air into a designated safe room in civilian
homes, through appropriate filters, at a rate high enough to
maintain a positive air pressure in the room of at least about 0.3
inches water, and preferably about 0.4 to about 0.6 inches water
(typically about 100 to about 125 Pascals). Since it is
characteristic of civilian rooms, especially older existing
structures, to leak air at high rates through porous dry wall and
concrete surfaces, visible cracks should be caulked, doors weather
stripped, windows covered with polyethylene sheets and duct taped
around sheet edges, and all walls, floors, and ceilings painted
with a relatively impermeable paint (e.g., epoxy or similar paint
products). With most leaks sealed in this manner, motors can be run
at low speeds (which allows for efficient operation of filters and
lower power consumption) and positive pressure can be maintained
easily in the room. Airborne viruses, bacteria, toxins, radioactive
particles and war gases cannot enter such a safe room because of
the positive pressure and the efficient sealing of all the room
surfaces by relatively impermeable paint polymers to even small gas
molecules such as nitrogen and oxygen. If these pathogenic agents
cannot enter the safe room, they cannot enter the airways of safe
room occupants and cause illness and death.
[0026] Air from the blower enters a filtering element prior to
entering the breathing space within the safe room. The filtering
element should effectively remove biological agent particles
greater than about 0.3 microns in diameter from the air. Suitable
filtering mediums include, for example, high efficiency particulate
air (HEPA) filters, ultra-low particle air (ULPA) filters, filters
using an electrostatic material such as Advanced Electret Media
(AEM; 3M, Minneapolis, Minn.) as described in U.S. Pat. Nos.
5,472,481, 5,350,620, and 5,411,576 (which are hereby incorporated
by reference), and the like so long as they exclude particles
having a diameter of greater than about 0.3 microns (and more
preferably greater than about 0.2 microns) without exhibiting
excess pressure gradients during use. Generally, HEPA filters are
preferred.
[0027] After being filtered, the air passes into the breathing
space of the safe room. Air pressure sensors are used to monitor
the air pressure inside the safe room and compare it to the
pressure outside the safe room to insure a positive pressure above
a preset level within the safe room. Data from the air pressure
sensor is communicated to a controller which, in turn, can vary the
speed of the variable air blower to maintain the desired positive
air pressure in the safe room. Generally, a positive air pressure
of at least about 0.3 inches water, and preferably about 0.4 to
about 0.6 inches water (typically about 100 to about 125 Pascals),
is maintained in the room. A carbon dioxide sensor (e.g., an infra
red CO.sub.2 sensor) is also connected to the controller to
maintain the carbon dioxide levels within the safe room to
acceptable levels. When the carbon dioxide in the safe room exceeds
a predetermined level (generally a carbon dioxide level of about
0.3 percent), the controller will be activated to lower the carbon
dioxide level. For example, the controller could activate a damper
in an exhaust port whereby carbon dioxide rich air could be
expelled outside the safe room; preferably, the controller would
simultaneously speed up the variable speed motor to force the
carbon dioxide rich air out more quickly. Once the carbon dioxide
level is reduced to an acceptable level within the safe room, the
controller would act to close the damper while simultaneously
reducing the speed of the variable speed motor to a level to
maintain the desired positive pressure within the safe room.
Alternatively, a carbon dioxide scrubber system using hydroxides or
other absorbents could be used to reduce the carbon dioxide levels;
in this case, the control would divert at least a portion of the
inside air though the scrubber until acceptable carbon dioxide
levels are obtained. Preferably, the carbon dioxide system
comprises the exhaust system alone or in combination with the
carbon dioxide scrubber.
[0028] A schematic of the system (not to scale) is shown in FIG. 1.
A sealable inlet opening 10 in the wall of the safe room allows air
from an adjacent room to be drawn through tubing 12 by variable
speed blower 14. The air from the variable speed blower 14 passes
through tube 16, through particulate filtering element 18, and into
the breathing space in the safe room (indicated by arrow 20).
Although not shown in FIG. 1, a optional war or chemical gas filter
could be combined with particulate filtering element 18 to provide
protection against combined biological and chemical attacks or
chemical only attacks. The controller 28, preferably of a
programable type, collects air pressure data from air pressure
sensor 26 via line 24 and carbon dioxide data from carbon dioxide
sensor 30 via line 32 and uses this data to control the speed of
the variable speed blower 14 via line 22 and, thus, the conditions
within the safe room.
[0029] During normal operation, the controller 28 uses the pressure
data from air pressure sensor 26 to maintain a positive air
pressure within the safe room of a predetermined level by
controlling the speed of the variable speed motor 14. Generally, a
positive air pressure of at least about 0.3 inches water, and
preferably about 0.4 to about 0.6 inches water (typically about 100
to about 125 Pascals), is maintained in the room. When abnormal
carbon dioxide levels are detected via carbon dioxide sensor 30,
the controller activates a damper (not shown) in exhaust port 36
whereby carbon dioxide rich air can be expelled outside the safe
room (as shown by arrow 38); preferably, the controller would
simultaneously speed up the variable speed motor to force the
carbon dioxide rich air out more quickly. Once the carbon dioxide
sensor 32 detects safe carbon dioxide levels, the controller 28
will shut the exhaust port 36 and return control of the speed of
variable speed blower 18 to the air pressure sensor (to maintain a
positive air pressure of the desired magnitude in the safe
room).
[0030] The safe room in FIG. 1 shows a window 50 and a door 52. As
noted above, these would normally be sealed to limit air entry
around these elements. Normally, plastic film would be used to seal
such windows (with duct tape used to seal the edges of the plastic
film) and weather stripping used to seal the door. Likewise,
caulking can be used to seal visible cracks in walls as well as to
seal around electrical outlets, intersections of walls, walls and
floor, and walls a ceiling. It has generally been found that such
sealing techniques, although helpful, are not sufficient,
especially in older homes or apartments, to allow maintenance of
the desired positive air pressure without running the variable
speed blower at such a high rate that the efficiency of the
filtering elements is significantly compromised. Coating all walls,
floors, and ceilings with a relatively impermeable paint (e.g.,
epoxy or similar paint products) in combination with these just
mentioned sealing techniques has been found to be effective. With
most leaks sealed in this manner, motors can be run at low speeds
(which allows for efficient operation of filters and lower power
consumption) and positive pressure can be maintained easily in the
room.
[0031] As noted above, FIG. 1 is not to scale. The actual system
can be relatively small in size and can, if desired, be placed in a
cabinet or other furniture unit. The holes through the walls to
allow air from an adjacent room to be filter and used to provide a
positive pressure in the safe room can, of course, be covered by
grills or other attractive coverings when not in use. Thus, the
room does not need to look like a safe room and can be used for
other purposes. Only in the event of an attack would the safe room
need to be operated. Because of the small size, relatively small
cost, and the ability to use the room for other purposes, the
present safe room system can be easily installed in both
new-construction or existing homes, apartments, and the like.
[0032] FIG. 2 provides flow charts illustrating controller programs
for operating the safe room. FIG. 2A illustrates normal operation
whereby the speed of the blower is controlled to obtain the desired
positive air pressure in the safe room. FIG. 2B illustrates
monitoring and control of the carbon dioxide levels in the safe
room. Preferably controller 28 is programmable to allow easy
control of the safe room using these, or similar, programming
techniques.
[0033] Using an approximately 50 to 60 year old civilian, frame
construction single family house near the Notre Dame campus, a
positive pressure safe room supplied with HEPA and activated carbon
(preferably ASZM TEDA carbon filters) filtered air was evaluated.
Initially the civilian residential room selected for study leaked
air diffusely, not only around portals (door and windows) but
diffusely through dry wall surfaces on the floor, ceiling, and
walls. Caulking and sealing the door, windows, electric plugs,
vents and wall floor seams did not significantly reduce the leaks.
The blower motor had to run at 500 cfm or higher to maintain a
positive pressure of only 0.1-0.2 inches water. Painting the walls,
ceiling, and floor with an epoxy paint (Sherwin Williams EPO paint;
approximately 10-17 mils thick) significantly reduced leakage. With
the addition of the paint, a positive pressure of about 0.4 to
about 0.5 inches water could be easily maintained by operating the
blower at only about 70 to about 90 cfm. This positive air pressure
is sufficient to prevent particles or gas from entering the room
through cracks or through the walls while allowing a sufficiently
slow blower speed to operate the filter efficiently. The easily
maintained pressure of 0.4-0.5 inches water (100-125 Pascals) has
no adverse effects on human beings. A differential pressure monitor
that compared safe room pressure to that of the adjacent room was
used. The pressure remained constant at about 0.5 inches water for
hours and was kept constant by a Nimbus Smart Fan motor controller.
Pressure and CO.sub.2 were monitored constantly. The CO.sub.2 level
was kept below 0.3 percent. If CO.sub.2 exceeded 0.3 percent, a
damper was opened and air allowed to leave the room until the high
CO.sub.2 was normalized. The filter element consisted of 31 square
feet of pleated HEPA, a 1 inch thick layer of activated carbon, and
an electrostatic prefilter. The HEPA filter protect against
pathogenic bacteria, toxins, and/or viruses on particles by
removing the particles from the air stream. War or chemical gases
(as well as CO.sub.2) can be removed by the optional activated
carbon filter. Preferably a panel of multiple (e.g., 4 to 6) deep
cycle marine batteries can back up the electrical ac motor. This
would be used if there were a power outage. For example, using 6
such batteries in a 1400 cubic foot room could provide power for
about 15 hours to run the motor.
[0034] In addition to sealing obvious leaks around the room
(including windows and doors), room preparation should be include
painting all wall, floor, and ceiling surfaces with a 10-16 mil
layer of suitable epoxy or other suitable paint. This seals out
pathogens and markedly slows egress of air from the room allowing
the motor to operate under 80-90 cfm. This also reduces battery
drain and prolongs the backup power life of the battery pack and
allows maintenance of filter efficiency in removing gases and
pathogenic particles.
[0035] The present biodefense home system of the present invention
is especially adapted for use with biomask disclosed in U.S. patent
application Ser. No. 10/316,474 and an integrated defense system
coordinated by the federal government or other responsible
authority. Once a signal of danger is give, the biomask is used to
allow individuals to travel to the safe room. The integrated
defense system would also provide information during the attack and
give the clear signal when it is safe to exit the safe room. The
integrated defense system would rely on boundary layer meteorology,
air sampling, and testing; to provide the populations of cities and
their suburbs with real time signals for use of masks and safe
rooms.
[0036] In one embodiment, the system uses a Fantech FKD10x1 blower
motor (EBM, Germany), flexible tubing from the wall of an adjacent
room to the blower, and HEPA filters downstream from the motor and
when needed a 1 inch thick 11 inch long hollow cylinder, internal
diameter 8 inches, containing ASZM TEDA carbon. A Nimbus controller
attaches to the motor and the keeps room pressure constantly at 0.5
inches water and the CO.sub.2 sensor (Telaire) is attached to a 3''
wall exhaust damper and a recirculation port upstream from the
blower motor and opens this as well as the damper when CO.sub.2
exceeds a predetermined value (generally about 0.3 percent) and
closes them when it is less than another predetermined value
(generally about 0.2 percent). Preferably, operation is automatic
once the appropriate parameters are inputted. If desired, displays
and alarms can be incorporated into the system to indicate normal
and abnormal operation.
[0037] In another embodiment, the biological home defense system
employs a centrifugal blower (generally about 25 lbs), a flexible,
gas/particle impermeable tubing 10'' diameter, 2-4 feet long with
an attached metal gasket with rubber or plastic seal at one end
that passes through a wall to an adjacent residential room. The non
gasket end attaches to the intake port of the centrifugal blower
motor and this is held in place by a tightened sealing ring. A
hollow plastic or metal cylinder housing of 10'' diameter and
height of 24'' is used to contain a 10'' diameter electrostatic
filter above which is placed a 10'' diameter HEPA pleated filter
(filter area of about 31 ft.sup.2). The top 12 inches of the
housing has a 1 1/12 inch thick circular layer of TEDA ASZM carbon
(internal diameter of about 7-8 inches). The top cap of the upper
housing may be removed leaving a clear path for HEPA filtered air
to enter the room in the absence of war gases. The motor controller
and power cord are attached to the controller or control box of the
motor. The motor controller contains a differential pressure
sensor; and motor speed is maintained at a flow rate that keeps the
room at positive pressure of about 0.4 to about 0.5 inches water. A
Nimbus Smart Fan motor controller can be used for this purpose. A
CO.sub.2 sensor having a LCD (Telaire or Honeywell) is used to
control an exhaust damper and/or a CO.sub.2 scrubber system. These
exhaust or removal systems are activated if room CO.sub.2 increases
above about 0.3 percent and deactivated as it drops below about 0.2
percent. This prevents CO.sub.2 buildup in the partially sealed
room and allows excess CO.sub.2 to escape preventing any even
remote risk of asphyxia.
[0038] Although not shown in the figures and as indicated in the
discussion above, the biological defense systems of this invention
may also have an optional chemical filter to provide protection
against combined biological and chemical attacks or chemical only
attacks. Such optional chemical filters could employ, for example,
activated carbon absorbent or other chemical absorbents.
[0039] Generally, the filtering element used will not allow
particles greater than about 0.3 microns to pass through. Suitable
filtering mediums include, for example, HEPA filters, ultra-low
particulate air (ULPA) filters, filters using an electrostatic
material such as Advanced Electret Media (3M, Minneapolis, Minn.)
as described in U.S. Pat. Nos. 5,472,481, 5,350,620, and 5,411,576
(which are hereby incorporated by reference), and the like so long
as they exclude particles having a diameter of greater than about
0.3 microns (preferably greater than about 0.2 microns) without
exhibiting excess pressure gradients during use. Even more
preferably, a HEPA or ULPA filter combined with an electrostatic
material filter can be used to provide increased protection.
[0040] As noted above, a leaky old room in a private home was
converted to into a non-leaky, positive pressure, safe room. We
produced the positive pressure room by using potentially
contaminated air from an adjacent unsealed room brought in by a
Fantech FKD blower motor. This air was filtered through 31 ft2 of
HEPA (for bioweapons) and TEDA ASZM carbon filters (for war gases).
The filtered air was brought in to the safe room at a rate that
exceeded the maximal leak rate of the prepared sealed safe room.
This created a positive pressure of 0.4-0.5 inches water (100-125
Pascals); such a pressure made the room impenetrable to bioagents
and war gases. Because of room pretreatment to reduce leaks, the
blower motor could operate at a very low air flow rate of 70 to 80
cfm. This pretreatment designed for very leaky residential rooms
consisted of sealing vents, use of caulking about windows and
doors, plugging electrical outlets, covering windows with
polyethylene sheets sealed along the edges with duct tape, and
painting all six room surfaces with epoxy or other suitable paint.
A motor controller was combined with a differential pressure
manometer to maintain enough filtered air flow to keep the room at
any positive pressure desired. An infra red CO.sub.2 sensor was a
safety feature that opened a damper to allow controlled outflow
from the room if CO.sub.2 levels rose above 0.3 percent. The blower
would respond temporarily to the open damper by speeding up until
the CO.sub.2 level was below 0.2 percent when the damper would
close. This safe room system measures positive pressure
continuously and uses it to control motor speed to maintain
whatever constant positive pressure is desired. This safe room
systems measures CO.sub.2 levels and uses this measurement to open
a damper to exhaust CO.sub.2 air. It could also control a
recirculation pathway that is connected to the air flow system,
upstream from the motor, which uses calcium hydroxide to
CO.sub.2.
[0041] The biological warfare masks of our previous invention and
the safe rooms provided by the present invention are ideally suited
for use in a general method for protecting civilian populations.
Moreover, the biological warfare systems of this invention are
ideally suited for use in a method for protecting a population at
risk of exposure to biological weapons of mass destruction
containing biological agents, said method comprising: (1) making
biological defense systems and instructions for their use during a
biological warfare attack available to the population; (2)
monitoring for biological warfare attack; (3) in the event of
attack or during periods of high potential of attack, evaluating
current and predicted weather patterns in the geographic areas
within, adjacent to, and downwind of, the biological warfare attack
to determine likely distribution of significant amounts of the
biological agents within the geographic areas; (4) alerting the
population and directing the use of the biological defense systems
within the geographic areas of likely distribution of the
biological agents; (5) reevaluating, based on current and predicted
weather patterns and data regarding actual distribution of the
biological agents within the geographic areas, updated likely
distribution of significant amounts of the biological agents within
the geographic areas over time to provide updates; (6) reporting
the updates to the population with, as appropriate, instructions
for continued use or termination of the use of the biological
defense systems within the geographic areas of updated likely
distribution of the biological agents or within new geographic
areas of updated likely distribution of the biological agents; and
(7) repeating steps (5) and (6) until no significant risk of
exposure remains.
[0042] This biological defense system is designed to be available
to an at-risk population. Although any population may be considered
at-risk of a terrorist attack, large population centers (i.e.,
major cities) are more likely to be targeted. The systems may be
distributed by local, state, or national governments or may be made
available to the general public through retail outlets. The method
also involves monitoring (preferably continuous monitoring) for
such biological warfare attack. Once such an attack is detected or
if the risk of such attack is high, weather conditions and patterns
in the vicinity of the target area are to be evaluated in order to
determine the likely geographic distribution of biological agents
from such an attack and the areas of potentially significant
exposure. Especially important weather conditions to be considered
are temperature inversions and wind conditions (especially
conditions involving low or no winds). Temperature inversions and
low ground wind speeds will tend to keep the biological agent cloud
intact, close to the ground, and delay its dispersion, thereby
increasing the risk of exposure to the population in the area. On
the other hand, high wind speed and the absence of temperature
inversions will tend to disperse the biological agent cloud and
reduce the risk of significant exposure.
[0043] Once the areas of potentially significant exposure have been
determined, instructions and warnings to the affected population
should be issued. Such instructions, which can be issued through
local TV and radio outlets, local emergency broadcast or other
warning systems, National Oceanic and Atmospheric Administration
(NOAA) weather radio, should include directions on when and how to
use biological defense masks and the biological home defense
systems as well as other information (e.g., protect food and water
supplies from contact with outside air, and the like). Evaluation
should continue to provide updated assessments for the areas at
risk in the initial attack as well as to issue new warnings to
other areas that may be later threatened by the attack (or other
attacks that may follow). The continued evaluation can also
incorporate data from measurements of actual exposure to the
biological warfare agent (in addition to data regarding actual and
expected weather conditions). Actual exposure data could be
generated, for example, using specific biochemical or biological
tests (e.g., PCR and the like). Generally, safe room usage should
continue until an "all-clear" message is issued. Such an
"all-clear" message can generally be issued about 1 to 2 hours
after the temperature inversion has lifted, the wind speed
increased significantly, or actual biochemical exposure data
indicates the threat has passed.
[0044] As noted above, the present invention can also be used to
create safe rooms to benefit individuals with severe asthma, severe
upper airway allergies, and/or similar debilitating or life
threatening respiratory conditions. This invention may also be used
to create isolation rooms in the home and/or in non-public or
public buildings (e.g., hospitals, nursing homes, and the like);
the ability to quickly and inexpensively create such isolation
rooms could be especially useful, for example, in case of an
influenza pandemic.
[0045] For a safe room designed for respiratory or similar
conditions, air entering the room can be limited to air from
outside the dwelling or an adjacent room that is blown into the
room by the motor and passes through the filter-containing housing
to enter the room; preferably a HEPA filter is used. In such
applications, a chemical filter will typically not be needed;
typically, the CO.sub.2 indicator or the wall damper for removal of
CO.sub.2 will not be required in this modification. Moreover,
sealing room surfaces will not be needed unless wall penetration by
allergens is a problem. If the room surfaces are sealed, then the
CO.sub.2 indicator and the wall damper to control CO.sub.2 levels
should be used.
[0046] A modification of the above described hardware can be used
to create an isolation room for family members who are ill with
pandemic influenza (such as avian H5N1) or highly contagious
diseases treated in the home to protect well family members and
visiting friends. The chemical filter will typically be unnecessary
and can be removed. A flexible air-impermeable duct can connected
to the open end of the filter (preferably HEPA) housing. This duct
will be connected distally to an outside adjacent wall or window
gasket so that air will be blown through the motor from the sick
room, through the filter, and then vented to the exterior of the
home to avoid contaminating the outside environment. The motor
controller should maintain a slight negative room pressure
(typically about 0.2 to about 0.3 inches water gauge (Wg)) relative
to other rooms in the house and the outside air. In the event of
pandemic avian influenza there may be thousands of ill persons that
will be turned away from hospitals with limited numbers of
isolation rooms (typically 3-4 per hospital). In the home, use of
HEPA nose mouth covering disposable masks can be used to protect
the well persons who enter the room. Additionally disposable gowns
and gloves can also be used by those nursing the ill patient(s).
Such simple technology should prevent viral contamination of the
entire home and should result in reduction of family morbidity and
mortality. This hardware can also be used by hospitals to rapidly
and inexpensively increase their numbers of isolation rooms.
Sealing of walls might be required in some leaky isolation rooms
with porous dry wall or concrete plaster surfaces to allow
attainment of negative isolation room pressures.
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