| These
replacement filters are of the highest quality. They are
all easily replaced by using simple hand tools (two Crescent
wrenches) and a suitable receptacle such as a plastic bag
to place to old filter in. For more information about how
to replace the filters, please see the Safe Cell manual.
All
of these filters come with the Safe
Cell:
Pre-filters
The pre-filters are designed to extend the life of the HEPA
filter by trapping both large and small particles. The first
filter is the roughing filter with an average efficiency
of 25 to 30 percent when tested in accordance with ASHRAE
52.1. The roughing filter extends the life of the intermediate
filter or pre-filter and reduces its change frequency. The
second filter is the intermediate filter with an average
efficiency of 80 to 85 percent when tested in accordance
with ASHRAE 52.1.
The
HEPA filter
The nuclear grade HEPA filter is a special filter we have
made just for our application.Each HEPA filter is individually
tested to MIL-STD-282 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 an individual serial number.
Every
HEPA filter is individually DOP tested: 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.
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).
- Media:
Water repellant glass micro fiber 99.97% True HEPA cell
type (A)
-
Cell Side Material: Fire retardant particle board
-
Separators: Aluminum
Bond: Polyurethane foam
-
Gasket Material: Neoprene (RE43E1)
-
Gasket Location: Both sides
-
Factory Test: Certified 99.97% (DOP)
-
UL 866 Label: Required:
Carbon
adsorber
The nuclear grade war gas adsorber is a block sieve adsorption
filter cell consisting of two containment medias and a center
block of blended granual nuclear grade war gas carbon and
ASZM-TEDA.
This
special blend of two kinds of activated carbon adsorbs warfare
gases and radioactive iodine in order to meet the requirements
of US Army Corps of Engineers ETL
1110-3-498 standard for war gas removal.
Carbon
blend specifications:
-
Activated impregnated NUK-TK TEDA Nuclear grade TEDA for
removal of radio active iodine
-
ASZM-TEDA copper-silver-zinc-molylebeunm-triethylenediamine
Critical
standards that we meet or exceed:
- ASTM
D 2854-1996: industry standard test method for apparent
density of activated carbon
-
ASTM D 2867-1999: industry standard test method for moisture
in activated carbon
-
ASTM D 3802-1997: industry standard test method for ball-pan
hardness of activated carbon
-
ASTM D 3467: activity for CCL - 60% minimum
-
ASTM D 2862/D5158: particle size: 4X8 Mesh U.S.
-
ASTM D 3838: pH aqueous extract - 9.2 minimum
- ASTM
D 3466: ignition temperature 330C
-
ASTM D 3803: radioactive iodine removal
-
Impregnated with 2.1 Potassium iodide, 3.1% TEDA
-
EA C 1704-1992: chemical research development and engineering
center purchase
How
long will a set of filters last?
That's
sort of a loaded question. Room air filter manufactures
can know with some certainty what their filters will be
challenged with. With NBC filters, the challenge is unknown.
We saw on 9-11-2001 a few inches of fine dust on the streets
of New York. Any particulate filter will quickly clog if
it is fed that amount of dust. On the other end of the spectrum,
a light dusting of fallout won't do much to the filter.
In fact, particulate filters (pre-filters and the HEPA)
actually filter better as they load up. The particulates
that they catch act to increase the area of the filter.
The down side is that as the filter loads up, it puts out
less airflow.
The carbon adsorber is a different situation. It does not
adsorb gases better as it loads up. It uses a process called
adsorption to attract and hold gas particles on the surface
of the carbon. It does not care what kind of gas it is adsorbing
- that is why we like to see the filter buttoned up with
the shipping caps until it is needed. Water vapor is a true
gas that loves to adsorb to the carbon graduals. And when
the carbon loads up, the only feedback is that the carbon
adsorber increases in weight very slightly. If you had a
very accurate scale, you could measure the adsorber before
and after and tell if it's had it's life used up.
We tell people that our filters will last "one event."
That is, if you have a mushroom cloud on the horizon or
a nuclear plant releasing radiation upwind, that is an event.
When you receive the all clear, then it is time to take
the entire Safe Cell off the wall, take it outside, remove
the old filters, and install new ones. Notify your local
hazmat team about the contaminated filters.
When the headlines for the Japanese nuclear release started
to generate interest in NBC filters, we were out of replacement
filters within a couple of days. It's surprising the number
of people who don't purchase a spare filter set with their
Safe Cell. Our HEPA's are a month out from the manufacturer
and our carbon that we have blended just is also a month
out.
We
keep more than adequate stock of them for normal sales,
but we cannot anticipate the demand when there is a nuclear
event. The best way to ensure you have replacement
filters is to order them when you order your Safe Cell. |
