ML20009D200
| ML20009D200 | |
| Person / Time | |
|---|---|
| Site: | 07105958 |
| Issue date: | 04/30/1981 |
| From: | Farkas S ENERGY, DEPT. OF, IDAHO OPERATIONS OFFICE |
| To: | |
| Shared Package | |
| ML20009D196 | List: |
| References | |
| NUDOCS 8107230274 | |
| Download: ML20009D200 (3) | |
Text
r U.S. DEPARTMENT OF ENERGY IDAHO OPERATIONS OFFICE SAFETY EVALUATION KRYPTON SHIPPING CONTAINER USA /5958/ BL( DOE-ID)
APRIL 1981
SUMMARY
Processing Plant (ICPP)pany, Inc (ENIC0), operator of the Idaho Chem' cal Exxon Nuclear Idaho Com at the Idaho National Engineering Laboratory (INEL) submitted ENIC0 Report 1069, Addendun to ICP-1077 Safety Analysis Report for Packaging (SARP) Krypton Shipping Container USA /5958/BL(DOE-ID),
January 1981. This report was prepared by ENICO to justify the usage of as alternative gas cylinder (DOT Specification 3AA) and high-temperature valve (NUPR0 Bellows Valve - Series "T").
In addition, preshipment heliun and krypton leakage tests were included.
The Idaho Operations Office (ID) perf'ormed a comprehensive review of the subject Addendum, discussed Addendum details with ENICO tecnnical, operatio,ns, safety, and quality assurance personnel, and observed the performance of the various leak tests.
The ID staff has determined that the alternate cylinder ind valve provide a comparable degree of containment to the assembly (DOT
.ipecification 3A and Kerotest Valve) authorized by the original Certificate of Compliance. In addition, the implementation of the preshipment heliun and krypton gas leakage tests on each cylinder / valve assembly used, assures that krypton shipments meet the packaging requirements established in ERDAM 0529, " Safety Standards for the Packaging of Fissile and Other Radioactive Materials," (D0E Order 5480),10 CFR Part 71, " Packaging of Radioactive Materials for Transport and Transportation of Radioactive Materials Under Certain Conditions," and 49 CFR Parts 170-189, " Hazardous Materials Regulations of the Department of Transportation (00T)."
. Revision 1 to the Certificate of Compliance for USA /5958/BL(00E-ID) has been issued by the DOE Idaho Operations Office, 550 Second Street, Idaho Falls, Idaho, 83401.
PRIMARY CONTAINER The D0T Specification 3AA Cylinder has the same physical dimensions as the DOT Specification 3A Cylinder and provides the equivalent degree of containment of the radioactive materials. The only difference between the two cylinders is the added manufacturer's certification of construction materials and quality control measures specific for the DOT Specification 3 AA cylinder.
I CLOSURE VALVE In order to provide an alternate valve to the Kerotest Valve previously approved, ENICO selected the NUPRO high-temperature valve (Series "T").
The NUPR0 Valve (Series "T") is an all-steel valve with a metal to metal 1925 r
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seal at the recommended torque of 50 in. lbs.
In order to preclude leakage between the bonnet and the valve body, a torque value of 450-550 in-lbs. is applied to the one inch joining nut on the TAG series.
The bonnet is welded to the valve body in the TAW series.
Because the NUPRO Valve is constructed of a variety of steel parts with different coefficients of expansion, ENIC0 conducted a series of tests to demonstrate that under established container loading and transport conditions, the valve would retain the radioactive gas.
In these tests four NUPRO Valves, fitted to cylinders pressurized with helim (raaging from 1 atm to 55 atm), were subjected to a varigty of heat transients ranging from g
ambient temperature (25 C) to 200 C and monitored for gas leakage through the valves.
heat transients, gas leakage between 8 x 10-g (cm /sec abd 3m3ss spectrom When measured with a heli m detect during thg/sec was observed. By assning the maximum cylinder logding x kO-cm (74,000 curies of krypton 85) and the maximm leak rate (3 x 10- cm /sec) for the duration of one week, the total leak was conservatively estimated to be approximately 0.03 curies of krypton 85. These tests demonstrated that the NUPRO Valve provides adequate retention of the primary container contents and the leak rate is well within that specified in ANSI Standard N14.5. As an added precaution, a brass cap is attached to the outlet prior to shipment. This provides an additional barrier to the gas that may leak through the valve seat.
This leakage rate presents a minimal radiological hazard to shipment handlers, carrier personnel, and the general public.
LEAK TEST OF CYLINDER / VALVE ASSEMBLY In addition to the leak test performed specifically for the closure valve, a leak test of the entire primary containment system was performed.
In this case a helim-pressurized cylinder (1 atm), at anbient temperature, was placed within an evacuated (0.2 microns) steel chamber.
The chanber atmosphere was tested (over a period of several hours) with the use of the helim detector previously described.
In this configuration, leaks past the valve stem, closure plug, and fitting between the va linder were checked for leak tightness (i.e., less than 1 x 10-}ve and cy/sec.).
atm -cm Test results demonstrated that the cylinder / valve assemblies were leak tight.
Cylinder / valve assemblies that fail to pass this test will not be used by ENICO for off-site krypton shipments.
KRYPTON 85 PRESHIPMENT CHECK WITH CONSTANT AIR MONITOR (CAM)
Field tests were conducted by ENICO to determine the feasibility of using a standard Constant Air Monitor (CAM) to monitor the leak rate from a cylinder loagedwithKrypton85. With a calculated minime sensitivity of 1.4 x 10 counts per minute per uCi/sec, the CAM registejed a rise of 100 uCi/sec) of krypton counts per minute when a known quantity (7.2 x 10 was released into the CAM detection chanber.
Based on calculations contained in ANSI Standard N14.5, " Anerican National Standard for Leakage Test On Packages for Shipment of Radioactive Materials,"
ENICO nas established a CAM response (rise) of 3800 counts per minute.as a criteritan for krypton shipments. This figure translates into a gas leak rate of 0.278 uCi/sec.
At this rate approximately 0.18 Ci would be released from the Krypton Shipping Container in one week (the amount of time required to ship the Krypton Shipping Container from the ICPP to Oak Ridge, Tennessee, the usual consignee fo-the Krypton 85 shipments). The dose rate on the exterior surface of a standard transport trailer would build up to 0.06 mrem /hr (an insignificant contribution above normal background).
CONCLUSIONS It is the opinion of ID that the use of the alternate gas cylinder (DOT Specification 3AA) and valve (NUPR0 Valve - Series "T") is acceptable and offers the same degree of safety to the DOT Specification 3A cylinder and Kerotest Valve authorized in the original Certificate of Compliance issued in August 1975.
We believe that the tests performed on the NUPR0 Valve demonstrate that the valve is generically adequate to provide the required containment.
In addition, if each cylinder / valve assembly passes the high pressure ambient heliun leak test as well a; the krypton leakage test, shipments in the Krypton Shipping Container should be in compliance with DOE, 00T, and Nuclear Regulatory Commission (NRC) regulations for the shipment of radio-active materials.
Accordingly, Revision 1 to the Certificate of Compliance for the Krypton Shipping Container - USA /5958/BL(D0E-ID) has been issued by ID with the appropriate nunber of copies distributed to ENIC0, registered users of this container, and 00E Headquarters (for subsequent transmittal to D0T and NRC.)
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S. W. Farkas, Health Physicist Radiological Safety Branch Operational Safety Division l
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