- HEPA Cell Specifications (Nuclear Grade) Used in MAGEN
8/18
The basic cell specifications and make up are the same as
that of the non-nuclear grade, with the exception that the
Lydair 3255 nuclear grade media we use has been qualified
and approved by the
U.S. Army Edgewood Research, Development and Engineering
Center (ERDEC)
MIL-F-51079 test reference number PATD-7697 & ASME AG-1
Section FC.
HEPA Cell Specifications: (Non-Nuclear Grade)
- Used in Models
SafeRoom 8/18
01. Media: Water repellent glass micro fiber 99.997%/99.999%
True HEPA cell type (F).
02. Cell Side Material: Fire retardant particleboard.
03. Separators: Aluminum.
04. Bond: Polyurethane foam.
05 Gasket Material: Neoprene (RE43E1) .
06. Gasket Location: Both sides.
07. Factory Test: Certified 99.997% (DOP).
08. UL 866 Label: Required.
HEPA filter cell:
As developed by the Atomic Energy Commission and used in nuclear
power stations, hospitals and bio-containment laboratories.
Guaranteed Performance:
Each HEPA filter is individually tested before it leaves the
factory, Your assurance that it meets rated efficiency. The
penetration and actual airflow rate are indicated on the label.
Each filter is also assigned a serial number and a permanent
record is kept of the materials of contraction and performance.
DOP Test: This has been
the industry standard test method for many years. It is conducted
using a forward light scattering photometer. The HEPA is challenged
with 0.3 micrometer particles of dioctyl-phthalate (DOP).
By measuring the upstream and downstream concentration of
these particles, the HEPA filter cell efficiency can be calculated.
Factory System Test:
Sample system flow measurements are conducted and documented
by a factory technician to insure that the assembled filtration
unit has sufficient air flow and pressure at the output to
attain a pressure reading of 0.04 inch/wg. in a 1,500 ft/3
room.
Documentation: All
SafeRoom Air Systems comes complete with an illustrated owners
manual documenting the installation details in graphic and
text format, all steps are detailed in such a manner that
they could be understood and followed by a non-English reading
person.
Underwriters Laboratories
Classification UL 586: This classification to
insure that each HEPA filter cell is individually tested at
the factory. Additionally, representative HEPA filter cells
are tested by UL to ensure that they provide their rated HEPA
level filtration, after being subjected to the following conditions
of a high moisture environment of (90% R.H.), a high temperature
environment of (371 deg/C), low temperature environment of
(-3 deg/C). UL also subjects the HEPA filter cell to a spot
flame test of (954 deg/C).
Gas Absorption
Cell Specifications: Used in SafeRoom 8/18
01. Cell Side Material: Fire retardant particleboard.
02. Baffles: Aluminum.
03. Bond: Polyurethane glue sealant.
04. Gasket Material: Neoprene (RE43E1) .
05. Gasket Location: exhaust side.
06. Factory Test: certified flow manometer, (See Department
of the U.S. Army Ref. 06-A)
07. Media: Activated coconut shell carbon, (See Department
of the US Army Ref. 07-A)
Department
of the US Army Ref. 06-A: Corps of Engineers requirement
for Class II NBC/CBR Toxic Free Overpressure Systems (TFA),
as outlined in Appendix E, section E-2, par.-1, of ETL 1110-3-498.
24 February 1999 (Carbon Absorber Residence time of 0.25 sec.)- Department of the US Army Ref. 07-A: Corps
of Engineers requirement for Class II NBC/CBR Toxic Free Overpressure
Systems (TFA), as outlined in Appendix E, section E-3, par.-5,
of ETL 1110-3-498. 24 February1999. (ASZM-TEDA Carbon Conforming
to EA-C-1704)
In replying to the many hundreds of people desiring more information,
we have developed some text that includes a discussion of
some the specifications that we meet. Here are two of them:
Discussion number one
There are two basic engineering requirements to filtering
air in a nuclear biological, and chemical Collective Protection
Shelter. First is the proper air overpressure in the room
relative to the outside air pressure to insure that no toxins
migrate into the room through the cracks. Second is the proper
filtration unit to insure that toxic agents are removed from
the incoming airstream.
To insure the satisfactory performance of our system we adhered
to the critical specifications of the Design Of Collective
Protection Shelters To Resist Chemical, Biological and Radiological
(CBR) Agents, Us Army Corps of Engineers ELT 1110-3-498 24
Feb. 1999. The only variant from the specifications is due
to the fact that the SafeRoom is designed for use in a room
of approximately 1500 ft/3 with an air output of 120-74 cfm
offering an overpressure of 0.04-0.02 in/wg. The military
version described in the specifications is for a much larger
area than 1500 ft/3 with an air output of 600 cfm but still
offering only an overpressure of 0.02 in/wg.
By Israeli standards IS4570 the SafeRoom-18 NBC System will
offer life support air supply for up to 17 persons in a closed
shelter. HEPA specifications:
1. Media: Water repellent glass micro fibre 99.97% True HEPA
cell type (A).
2. Cell side material: Fire retardant particleboard.
3. Separators: Aluminum.
4. Bond: Polyurethane foam.
5 Gasket materials: Neoprene (RE43E1).
6 Gasket location: Both sides.
7. Factory test: Certified 99.997% (DOP).
8. UL 586 label: Required.
HEPA filter cell: Was developed by the Atomic Energy Commission
and is used today in nuclear power stations, hospitals and
bio-containment laboratories. HEPA Guaranteed Performance
Documentation: Each HEPA filter is individually tested before
it leaves the factory, your assurance that it meets rated
efficiency. The penetration and actual airflow rate are indicated
on the label. Each filter is also assigned a serial number
and a permanent record is kept of the materials of contraction
and performance.
HEPA DOP Test: This has been the industry standard test method
for many years. It is conducted using a forward light scattering
photometer. The HEPA is challenged with 0.3 micrometer particles
of dioctyl-phthalate (DOP). By measuring the upstream and
downstream concentration of these particles, the HEPA filter
cell efficiency can be calculated. HEPA Underwriters Laboratories
Classification UL 586: This classification to insure that
each HEPA filter cell is individually tested at the factory.
Additionally, representative HEPA filter cells are tested
by UL to ensure that they provide their rated HEPA level filtration,
after being subjected to the following conditions of a high
moisture environment of (90% R.H.), a high temperature environment
of (371 deg/C), low temperature environment of (-3 deg/C).
UL also subjects the HEPA filter cell to a spot flame test
of (954 deg/C). Carbon war gas adsorber specifications: NUK-TK
ASZM-TEDA nuclear grade coconut shell blended carbon 5.4 kg.
Activity for CCL (ASTM D-3467) Moisture content (ASTM D-2867)
Hardness (ASTM D-3802) Bulk density (ASTM D-2854) Ash content
(ASTM D-2866) pH aqueous ext. (ASTM D-3838) Impregnate 2.1%
Potassium iodide 3.1% TEDA Radioiodine removal efficiency
ASTM D-3803 War gases: Hydrogen cyanide, Phosgene, Mustard
gas, Sarin, Racin, VX.
Blower specifications: The blower module including all electrical
circuitry is self contained. This feature is to accommodate
different electrical supply voltages such as a battery back-up.
110 volt AC 60 hertz 1.6 amp 250 cfm. 220 volt AC 50 hertz
0.3 amp 200 cfm. 12 volt DC 11.5 amp at 250 cfm. System air
output: 102 m3/hr at 1.5 SP 1.50 inch/wc
Discussion number two
The SafeRoom System is a portable positive pressure emergency
air filtration system designed to offer protection in the
event of a nuclear, biological or chemical attack.
The SafeRoom 18 has an air output of 120 cfm when configured
for nuclear and biological protection and 60 cfm configured
for full NBC protection with the gas adsorber installed. This
is sufficient air supply for 17 persons, assuming the lower
air output of 60 cfm and the higher of the two ASHARE requirements
of 5 cfm per person as sited below in the FUNDAMENTALS ASHRAE
standard.
The system works by drawing outside air through its filter
banks and introducing it into the shelter area creating a
slight overpressure. This overpressure is to keep any unfiltered
air from migrating back into the shelter area through the
cracks. The shelter must have an exhaust vent on an opposite
wall of the intake vent so that air change can take place
and Co2 build up does not become a problem. The desired overpressure
is .02 in/wg and may be measured with the air flow meter provided
with our test kit.
The SafeRoom 18 NBC unit was designed for use in a shelter
area of about 1500 Ft/3 but can be used in larger shelters
providing that the airflow and overpressure requirements are
meet. Because the amount of overpressure in the shelter and
airflow rates produced by the unit are a direct function of
the shelter construction or room tightness and is beyond our
control, we make no claims as to its suitability in any particular
installation other than the output a airflow of the unit itself.
In order to insure sufficient airflow rate and overpressure
state in a particular installation the guidelines specified
in the SafeRoom installation manual and instructions must
be followed.
For added safety we recommend the adherence to local building
code as well as the installation of a good Co2 monitor/alarm.
ASHRAE HANDBOOK 1985 FUNDAMENTALS VOLUME Section IV Load and
Energy Calculations Ch. 22 Ventilation and Infiltration (TC
4.3, Ventilation Requirements and Infiltration) Page 22.1
Minimum Outdoor Air Supply Rates: ASHARE Ventilation Standard
62-1981,1 defines minimum outdoor air supply rates for various
types of occupancy. These rates have been arrived at through
a consensus of experts working in the field. A minimum rate
of 5 cfm per person for sedentary activity and normal diet
holds the Co2 level in a space 0.25% under steady state conditions.
While normal healthy people tolerate 0.5% Co2 without undesirable
symptoms and nuclear submarines sometimes operate with 1%
Co2 in the atmosphere, a level of 0.25% provides a safety
factor for increased activity, unusual occupancy load or reduced
ventilation. ASHRAE HANDBOOK 1982 APPLICATIONS Environmental
Control for Survival 11.1-11.24 Page 11.4 Vitiation Factors:
Carbon dioxide concentration should not exceed 3% by volume
and preferably should be maintained below 0.5%. For a sedentary
man, 3 cfm (1.4 l/s) per person of fresh air will maintain
a Co2 concentration of 0.5%.
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