ORDELA MODEL 8210A FRISCH-GRID LARGE-AREA IONIZATION CHAMBER WITH ORDELA MODEL

Description

NICE ITEM HERE 1 ORDELA MODEL 8210A FRISCH-GRID LARGE AREA IONIZATION CHAMBER AND 1 ORDELA MODEL 8200A-AGM AUTOMATIC GAS MANAGEMENT CONTROLLER. UNITS COME WITH EVERYTHING SHOWN MANUALS SOFTWARE DISK 10 SEALED SAMPLE TRAYS. SELLING AS/IS AS I HAVE ONLY TESTED THE AUTOMATIC GAS MANAGEMENT CONTROLLER TO POWER ON WHICH IT DOES AND CAN BE SEEN DOING SO IN PHOTOS. I DO NOT HAVE THE CAPABILITIES NOR THE KNOWLEDGE TO TEST ANY FURTHER. BOTH UNIT ARE SUPER CLEAN UNITS. IONIZATION CHAMBER IS WELL OVER 100LBS SO WILL BE SHIPPING UNITS FREIGHT FOR A FLAT FEE OF 0.00 CAREFULLY PACKED AND FASTENED TO A PALLET AND INSURED TO A COMMERCIAL ADDRESSEE. PLEASE VIEW ALL PHOTOS AND IF YOU HAVE ANY QUESTIONS PLEASE DONT HESITATE TO ASK.
SPECIFICATIONS:
ACTIVE SAMPLE AREA:
25 cm. diameter (20 cm. x 25.4 cm. with planchet removed)
ENERGY RESOLUTION:
<50 keV FWHM
230
Th, 4.7 MeV
THERMAL NOISE:
30 keV FWHM
ALPHA EFFICIENCY:
>45% for a weightless, 5 cm. diameter sample
BETA EFFICIENCY:
Insensitive to beta and gamma radiation
BACKGROUND:
<3.0 x 10
-
5
cpm/cm
2
/100 keV (
0.002 cpm/cm
2
);
4 to 10 MeV
COUNTING GAS:
Ar
-
CH
4
(
P
-
10
), at <200 kPa absolute pressure
BIAS VOLTAGE:
Requires 3 kV at 100 μA; SHV
-
type connector
PREAMPLIFIER POWER:
+12 V at 20 ma; standard 9
-
pin D
-
type connector
COUNTER CONSTRUCTION:
BODY MATERIAL:
Nickel
-
plated steel
COUNTER VOLUME:
App
roximately 24 L; (35 cm. diameter, 25 cm. deep)
OVERALL DIMENSIONS:
44 cm. diameter, 40 cm. high
WEIGHT:
110 lbs. (net), 130
lbs (shipping)
Standard accessories, delivered with the Model 8210A are: (1) One low
-
noise preamplifier (ORDELA Model
QS
-
11), a
high
-
voltage filter and distribution network, and (2) 3
-
m
-
long (10 ft.) cables (BNC type for signal
and SHV type for high volta
ge) for interconnection of the Model 8210A with a standard amplifier and the
high
-
voltage power supply.
OPTIONAL ACCESSOR
IES
:
P
RESSURE/VACUUM CUTOF
F
SENSOR SWITCH
:
Disables high
voltage when vacuum is applied to
prevent damage to preamplifier FET.
Functio
ns with high voltage supplies that
require a short to ground to disable bias
voltage.
ORDELA Model 8208A
-
AMP/HV
Rack
-
mount (sta
ndard, 19” width) or
standalone, spectroscopy grade amplifier and high voltage power supply for the Frisch
-
grid.
Disable functio
n
works with OPTIONAL
PRESSURE/VACUUM CUTO
FF SENSOR
SWITCH
to protect preamplifier.
AMPLIFIER:
Continuously variable gain, x
13 to x45; integral nonlinearity, 0.05%.
HIGH VOLTAGE
:
Continuously variable from 0 to 3000 V, 0 to 1 mA; 6 mV peak
-
to
-
pe
ak ripple, 0.02% stability per 8 hours.
OPERATING TEMP
:
0 to 50° C.
SHIPPING WEIGHT:
6.8 kg
APPLICATIONS:
♦
Site Assessment/ Evaluation:
NO
chemical treatment of any kind required to
RAPIDLY
screen soil and other sample
s for
radionuclide contamination!
♦
Air Monitoring:
Monitor remediation projects in near
-
real
time!
Achieve Lower Limits of Det
ection (
LLD
)
of
4 x
10
-
2
Bq/m
3
(10
-
12
μ
Ci/mL) with only 10
minute count time (
0.4 m
3
/min.
or 14 cfm)!
♦
Soils:
Achieve an LLD
=
1.5 Bq/g
(40 pCi/g) with
100 mg soil samples,
10 minute preparation
time
, and only a
10 minute count time!
Resolution about
95 keV FWHM
for
239
Pu!
♦
Water Analysis:
Directly
spray water samples of 5
-
15 mL onto
the 25 cm diameter planchet, dry, and
count!
Boil larger volumes
and count on the Frisch
-
grid
to
increase sensitivity
!
♦
Smears, Swipes:
Don't cut your 20 x 25 cm fi
lter papers any
more! No compromise counting;
assay
whole
samples without cutting into non
-
homogeneous
pieces! Simultaneously
screen multiple samples
with the large, 507 cm
2
counting area.
♦
Mobile Laboratories:
Developed for the mobile laboratory
with
rugged
construction, yet light weight (110 lbs.) compared
to gas
-
flow proportional counters.
Equally at
home in the analytica
l laboratory!
DESCRIPTION:
The
ORDELA
Model
8210A
is a
large
-
area
, gridded
ionization chamber designed for
rapid
, direct alph
a
spectrometry of environmental soil, water, air filter, and
smear samples
1
. The 44 cm diameter x 40 cm high
cylindrical spectro
meter is made of mild
-
steel and
completely nickel
-
plated
for low
-
background
environmental counting and ease of decontamination.
Also, the Frisch
-
grid, anode, and supporting structure are
attached to the top and
disassemble as a unit
for
maintenance and dec
ontamination.
Alpha resolution of <50 keV FWHM is possible on low
-
mass samples as large as 25 cm in diameter.
Sample
preparatio
n is
easy
,
quick
, and
does not require time
-
and labor
-
intensive radiochemistry
or special laboratory
equipment. Soil samples a
re finely
ground
,
mixed
with
solution,
sprayed
onto 25 cm diameter, mirror
-
finish
stainless steel planchets, and
dried
under hea
t lamps.
Samples are then placed in the sliding tray assembly and
inserted into the chamber via a horizontal access port.
Alpha energy spectra are measured by
any
standard
multichannel analyzer (MCA).
Water samples
of from 5
-
to 15
-
mL can be
directl
y sprayed
onto the planchets and
counted
.
Air filter samples
and
smears
, up to 25 cm in
diameter, may be
directly counted
with
no sample
preparation
and without introducing inconsistencies due
to trimming of the samples.
Rectangular 20 cm x 25 cm
filter
papers
may also be counted by removing the 25 cm
diameter planchet and placing the filter directly onto the
horizontal sample tr
ay.
Short assay times
are possible
due to the
high counting efficiency
and
low backgrounds
of the model 8210A.
The real benefi
t of the 8210A is its performance!
Spectrometric soil measurements of
plutonium
and
americium
contamination are made at sensiti
vity levels of
7 pCi/g
in only
60
minutes! Here, the Frisch
-
grid
spectrometer is capable of
monitoring airborne
transuranic con
centrations
,
in near real
-
time!
Technicians can rapidly analyze soil, smear, and air filter
samples.
Rugged
construction of th
e model 8210A makes it an
ideal
analytical instrument both for
mobile laboratories
and for
benchtop use
in standard environmen
t
al counting
laboratories. An "O" ring
-
sealed, horizontal access port
allows
easy sample insertion/extraction
by a sliding tray
assembly.
P
-
10
(Ar
-
CH
4
) counting gas, at
up to 200
kPa
(two atmospheres) absolute pressure, is used for the Model
8210A.
The 82
10A
includes
a low
-
noise preamplifier, and a high
voltage filtering and biasing circuit. An
ORDELA
Model
8200A
-
AMP/HV
spectrosco
py grade amplifier and high
voltage bias supply, or equivalent, a
vacuum pump
, a
source of
P
-
10 gas with pressure regulators
, an
d
any
MCA
are additional instruments and equipment required
for operation of the 8210A.
Completely integrated systems are avail
able from
ORDELA
, Inc. Optimized and calibrated at our factory in
Oak Ridge, Tennessee, these complete systems minimize
install
ation time in your laboratory.
For
Simple
Alpha Spectrometry
1
Sill, Claude W.,
Health Physics Journal
, Vol. 69, No. 1, July, 1995, pp. 21
-
33.
Theory of Operation
The Frisch
-
grid counter operates by placing a sample on a
25 cm diameter, mirror
-
finish stainless steel pla
nchet and
inserting it inside the counter through the front
-
loading
access door. The chamber is evacuated and refilled with P
-
10 (Ar
-
CH
4
) counting gas, normally at more than
atmospheric pressure. Bias voltage is applied and amplifier
gain and MCA convers
ion gain are set to monitor selected
nuclides.
An alpha particle emitted from a source travels
in an approximately straight lin
e, producing
ionized particles and losing energy at a rate of
about 26 eV per electron/ion pair produced.
The length of the ioni
zation path depends upon
the counter gas pressure and the initial energy
of the alpha particle; e.g. a 10 MeV alpha
particle in
P
-
10 gas at 80 kPa (gauge) has a
range of about 4.1 cm. (1.6"). The sample
planchet is properly sized such that all alpha
emissi
ons will be contained within the active
volume of the counter. (
See figure at right for
cut
-
away view.
)
The high voltage bias cr
eates an electrostatic
field. The free electrons created by the
ionization process migrate toward the grid. As
they approach, th
ey are affected by the higher
electrostatic gradient between the Frisch
-
grid
and the anode, which reaches through the mesh
of th
e grid. Thus,
all
electrons are channeled
through the grid and collected on the anode.
Upon collection of these electrons, a cha
rge is
induced on the anode. Since the Frisch
-
grid
effectively normalizes the travel distance of all
electrons, the induced char
ge pulses have
magnitudes that are proportional to the number
of collected electrons, independent of their origin.
♦
Air Monitori
ng:
Achieve an
LLD
(Lower Limits of Detection) of up to
1 x
10
-
2
Bq/m
3
(10
-
12
μ
Ci/mL
) for 10 minute air samples taken
at
0.4 m
3
/
min.
(14 cfm)! Without waiting for decay of radon
daughters, obtain
resolutions
in the range of
75
-
100 keV
FWHM
for
whole
,
20
-
x 25 cm
air filter samples on
surface
-
loading filter media
! Monitor remediation
projects in near
-
real time!
♦
Soils:
RAPID
alpha
assay and screening. With 30 minute sample
preparation (and
NO
chemical procedures) achieve an
LLD
of
1.5 Bq/g
(or 40 pCi/g) fo
r 100 mg soil samples with
only
a 10 minute count time!
♦
Water Analysis:
Directly
spray water samples of 5
-
15 mL onto the 25 c
m
diameter planchet, dry, and count! Reduce larger volumes of
water by
simply boiling
and counting on the model 8210A
to
increas
e sensitivity
!
♦
Smears, Swipes:
No compromise counting;
assay whole samples without the
need to cut into non
-
homogeneous pieces!
Simultaneously
screen multiple samples with the extra large,
507 cm
2
sample counting area.
♦
Mobile Laboratories:
Rugged constru
ction, yet lighter than
(110 lbs.) even
portable gas
-
flow proportional counters. Well
-
suited for the
rigors of mobile laboratori
es, the Frisch
-
grid is equally at
home in the analytical laboratory!