ML20248A027
| ML20248A027 | |
| Person / Time | |
|---|---|
| Issue date: | 01/26/1996 |
| From: | Steven Baggett, Doug Broaddus NRC |
| To: | |
| Shared Package | |
| ML20248A032 | List: |
| References | |
| SSD, NUDOCS 9805290272 | |
| Download: ML20248A027 (7) | |
Text
_ _ _ _ _ - _ _.. _ - _ _ _ _ _ _ _ _ _ _ - - _ _ _ _ _ _ _ - _ _ -. _ _ _ _ _ _ _ _ _ _
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE NO.: NR-460-S-907-S DATE: January 26, 1996 PAGE 1 OF 6 SEALED SOURCE TYPE:
Beta Gauge Source MODEL:
3L2D MANUFACTURER / DISTRIBUTOR:
3M Health Physics Services 3M Center, Building 224-2E-06 St. Paul, MN' 55144-1000 ISOTOPE:
MAXIMUM ACTIVITY:
Promethium-147 150.0 millicuries (5.550 GBq)
LEAK TEST FREOUENCY:
6 Months PRINCIPAL USE:
(E) Beta Gauges l
CUSTOM SOURCE:
YES X
NO 9805290272 960126
~
- T99*p+T w
_-_____________-____-______-_-________a
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE NO : NR-460-S-907-S DATE: January 26, 1996 PAGE 2 OF G SEALED SOURCE TYPE:
Beta Gauge Source l
DESCRIPTION-The 3L2D is a singly-encapsulated beta source.
Promethium-147 l
(Pm-147) is absorbed into small ceramic particles using a heat treatment to create 3M Brand Radiating Microspheres.
The microspheres are then nickel plated and pressed, using a proprietary process, into an aluminum sheet about 0.050 in.
(0.127 cm) thick, 0.245 in. (0.622 cm) wide, and 1.875 in.
(4.763 cm) long, whose ends are semicircles with a 0.245 in.
(0.622 cm) diameter.
The microspheres are all embedded in the sheet to a depth equivalent (at least) to their diameters, so they will not fall off.
A further protection against loss of containment is 0.001 in. (0.003 cm) thick aluminum foil wrapped around the sheet.
A screen is pressed into the foil on the back side of the sheet to hold the foil together and the assembly is sealed with an epoxy cement.
The sheet is then inserted, microsphere side facing in, into a 1.875 in. (4.763 cm) long, 0.250 in. (0.635 cm) wide, 0.250 in.
(0.635 cm) deep chamber in a stainless steel, source housing.
The ends of the chamber are shaped like half-cylinders with a diameter of 0.250 in. (0.635 cm).
The housing itself is 3.375 in. (8.573 cm) long and 0.380 in. (0.965 cm) wide.
The housing is 0.060 in. (0.152 cm) thick over 0.500 in. (1.270 cm) of length at either end.
A 0.152 in. (0.386 cm) diameter hole is drilled through each end.
A raised area 0.300 in. (0.762 cm) high covering the middle 2.375 in. (6.033 cm) of length contains the source chamber where the source sheet is inserted.
The wall over the top of the chamber is 0.050 in. (0.127 cm) thick, with a hole 1.500 in. (3.810 cm) long and 0.125 in. (0.318 cm) wide whose ends are 0.125 in. (0.318 cm) diameter semicircles in its middle.
The hole serves as a window for the radiation.
After the source sheet is inserted into the housing chamber, a 1.875 in. (4.763 cm) long, 0.245 in. (0.622 cm) wide, and 0.180 in. (0.457 cm) thick, oval plug is inserted into the chamber.
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE NO.: NR-460-S-907-S DATE: January 26, 1996 PAGE 3 OF 6 i
l ERALED SOURCE TYPE:
Beta Gauge Source l
l l
DESCRIPTION: (Continued) l The plug is cemented in place using an epoxy cement, sealing the source sheet inside.
The housing and plug are both made from type 2024-T4 aluminum.
DIAGRAM:
See Attachment 1 LABELING:
The-exterior of the housing is engraved with the following:
XXX millicuries - Pm-147 Serial XXX Model 3L2D Date
. CONDITIONS OF NORMAL USE:
l 3M reported that this source is designed to be used in gauging l
applications, particularly in the gauging of very thin films.
j l
i PROTOTYPE TESTING:
3M reported that no prototype testing was conducted on this source, but relied on the prototype testing information of the previously approved 3M sealed source Model 3L2B which is similar in design and construction to the Model 3L2D source.
i l
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE NO.: NR-460-S-907-S DATE: January'26, 1996 PAGE 4 OF 6 SEALED SOURCE TYPE:
Beta Cauge Source EXTERNAL RADIATION LEVELS:
As referenced in the 1992 Revised Edition of the Health Physics and Radiological Health Handbook, Rules of Thumb, for a point source of beta radiation (neglecting self-and air-absorption) of a given source strength in curies, the dose rate at 0.394 in.
(1.0 cm) is approximately equal to 200.0 R/hr per mci (54.0 Gy/hr per MBq).
The variation with energy is small over a wide range.
Based upon this, beta dose rates were calculated for a 150.0 mci (5.550 GBq) Pm-147 sealed source ad 0.394 in. (1.0 cm) to be approximately 30,000 R/hr (300 Gy/hr).
These calculations are based upon the neglect of self-and air-absorption.
Also, the absorption due to the shielding material was not taken into consideration.
With the inclusion of the aluminum shielding and air-absorption, it is estimated that external radiation levels at 11.81 in, and 39.37 in. (30.00 cm and 100.0 cm) would be negligible given that the range in aluminum of beta particles from Pm-147 is approximately 0.002 in.
(0.005 cm) and less than 12.00 in. (30.48 cm) in air.
- Likewise, the dose rate at 0.394 in. (1.0 cm) calculated above would be expected to be significantly reduced.
OUALITY ASSURANCE AND CONTROL:
The following quality control procedures were followed during production of this source:
- 1. The aluminum sheet was smear tested after the microspheres were pressed into it.
- 2. The completed source was smear tested immediately after fabrication.
- 3. The completed source was smear tested again immediately l
prior to shipment.
I LIMITATIONS AND/OR OTHER CONSIDERATIONS OF USE:
This source may be used only by persons specifically licensed by the NRC or an Agreement State.
I a
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE NO.: NR-460-S-907-S DATE: January 26, 1996 PAGE 5 OF 6 SEALED SOURCE TYPE:
Beta Gauge Source LIMITATIONS AND/OR OTHER CONSIDERATIONS OF USE: (continued)
Handling, storage, use, transfer, and disposal:
to be determined by the licensing authority.
This source shall be leak tested at intervals not to exceed 6 months using techniques capable of detecting 0.005 microcurie (185.0 Bq) of removable contamination.
This registration sheet and the information contained within the references shall not be changed without the written consent of the NRC.
SAFETY ANALYSIS
SUMMARY
The Model 3L2D source is not a current product manufactured or distributed by 3M Health Physics Services.
However, 3M Health Physics Services will continue to receive 3L2D sources for disposal.
Based on our review of the Model 3L2D source, and the information and test data cited below, we continue tc conclude that this source is acceptable for specific licensing purposes.
Furthermore, we continue to conclude that the Model 3L2D source would be expected to maintain its containment integrity for normal conditions of use and accidental conditions which might occur during uses specified in this certificate.
REFERENCES:
The following supporting documents for the Model 3L2D sealed source are hereby incorporated by reference and are made a part of this registry document:
3M Health Physics Services' letters dated August 6,
- 1991, January 12, 1968, March 15, 1965, and January 13, 1965, with enclosures thereto.
REGISTRY.OF. RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED = SOURCE NO.: NR-460-S-907-S DATE: January 26, 1996 EAGE'6 OF 6 SEALED SOURCE TYPE:
Beta Gauge Source ISSUING AGENCY:
U.S. Nuclear Regulatory Commission Ib Date:
January 26. 1996 Reviewer:
Mvm Ddligl s A.
Broaddus Date:
January 26. 1996 Concurrence:
"Stev W (,
Baggett I
REGISTRY OF RADIOACTIVE SEALED SOURCES AND DEVICES SAFETY EVALUATION OF SEALED SOURCE.
NO.: NR-460-S-907-S DATE: January 26, 1996 ATTACHMENT 1
- 24(152)
.I25 ACTIVE. AREA i
. DRILL 2 HOLES
<f
,______4_____.______,
_gc
._3 3
3 I
i w _i _.._ L _ _
l' t
'l-
.j i
I
{
l I
}
r 1.500 ACTIVE AREA
.19 -j L
- 3. 0 0 0 - - - -
- --- -M
. d,
. _... _ 3, 3 7 5 _ _. _. _
- -.001*THK. ALVMINUM WINDOW
- 9..
o
,~
- -}'
- f <, i.i I
i
'l l'
1 T 1(
i i
/
.o l-B AC R P LU G -
O EPOX'T IN PLACE.
N CT E. :
0 \\5 0 M c. P M - 147 C ONT A I N E.D LN D M SRAt40 R AOI AT LN G mig R O SP H E RP.5 M AT 'L.
ALUM)NUM l
USED ON I
N ON/.15.19 %
nu y,
meus ie uscarsanocu.moanacono na v.
cM.
manamm ene, s.orie man
,,,, = H U LLE. AR P R0 05 PaoJ-oms.o macwi=so o.= =
GB
- Ol ]su eo5 ocu.s2
,1 PM- \\4 t 5 o URC,E.
~ ~ ~ " ". ' ".. *,...ro c.v m soy
..o..
m c.e.,e,-
3M MODE.L No. 3 L P_ D l.
e.....o....
. m MINNESOTA MINING & MANUFACTURING CO.
A i921-555 o..
= =. =.
_ _... _ _