Information Notice 1996-66, Recent Misadministrations Caused by Incorrect Calibrations of Strontium-90 Eye Applicators: Difference between revisions

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{{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDSWASHINGTON, D.C. 20555December 13, 1996NRC INFORMATION NOTICE 96-66: RECENT MISADMINISTRATIONS CAUSED BYINCORRECT CALIBRATIONS OF STRONTIUM-90EYE APPLICATORS
{{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY
 
COMMISSION
 
===OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS===
WASHINGTON, D.C. 20555 December 13, 1996 NRC INFORMATION
 
NOTICE 96-66: RECENT MISADMINISTRATIONS
 
CAUSED BY INCORRECT
 
CALIBRATIONS
 
OF STRONTIUM-90
 
===EYE APPLICATORS===


==Addressees==
==Addressees==
All U.S. Nuclear Regulatory Commission Medical Use Licensees authorized to usestrontium-90 (Sr-90) eye applicators.
All U.S. Nuclear Regulatory
 
Commission
 
Medical Use Licensees
 
authorized
 
to use strontium-90 (Sr-90) eye applicators.


==Purpose==
==Purpose==
The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to alert addressees to recent misadministrations caused by incorrectsource strength determinations of Sr-90 eye applicators. It is expected thatrecipients will review the information for applicability to their facilitiesand consider actions, as appropriate, to avoid similar problems. However,suggestions contained in this information notice are not NRC requirements;therefore, no specific action nor written response is required.DescriDtion of CircumstancesThe primary causes of two recent events have been problems with calibrationand calculation of the dose rates from Sr-90 applicators. As a result, theadministered doses were not within 20 percent of the prescribed dose.Case 1. In October 1995, during an inspection of a licensee authorized to usea Sr-90 eye applicator in Mayag~ez, Puerto Rico, it was determined that thecalibration record for the licensee's Sr-90 eye applicator was missing. Aprevious owner of the source lost the original calibration certificate, andhis medical physics consultant performed a check of the source strength. Thischeck was performed with an inappropriate measurement instrument and resultedin an incorrect determination of the source strength as 0.24 Gray (Gy)/sec 0(24 rad/sec). The licensee obtained the source in 1994 and relied on theerroneous source strength determination during treatments. Also, the sourcehad not been decay-corrected by either owner since 1990. NRC urged thelicensee to have the eye applicator recalibrated and to be instructed in the D Fc2proper method to calculate the decay of the source.The licensee subsequently had the eye applicator recalibrated by the NationalInstitute of Standards and Technology. The resultant recalibration revealed adose rate of 0.53 Gray (53 rad)/sec rather than the 0.24 Gy (24 rad)/sec usedby the licensee. The licensee had prescribed a total dose of between 10 to25 Gy (1000 to 2500 rad) for approximately9-0709036 f arr&0 C. Dr Ilt, 2a
The U.S. Nuclear Regulatory
 
Commission (NRC) is issuing this information
 
notice to alert addressees
 
to recent misadministrations
 
caused by incorrect source strength determinations
 
of Sr-90 eye applicators.
 
It is expected that recipients
 
will review the information
 
for applicability
 
to their facilities
 
and consider actions, as appropriate, to avoid similar problems.
 
However, suggestions
 
contained
 
in this information
 
notice are not NRC requirements;
therefore, no specific action nor written response is required.DescriDtion
 
of Circumstances
 
The primary causes of two recent events have been problems with calibration
 
and calculation
 
of the dose rates from Sr-90 applicators.
 
As a result, the administered
 
doses were not within 20 percent of the prescribed
 
dose.Case 1. In October 1995, during an inspection
 
of a licensee authorized
 
to use a Sr-90 eye applicator
 
in Mayag~ez, Puerto Rico, it was determined
 
that the calibration
 
record for the licensee's
 
Sr-90 eye applicator
 
was missing. A previous owner of the source lost the original calibration
 
certificate, and his medical physics consultant
 
performed
 
a check of the source strength.
 
This check was performed
 
with an inappropriate
 
measurement
 
instrument
 
and resulted in an incorrect
 
determination
 
of the source strength as 0.24 Gray (Gy)/sec 0 (24 rad/sec).
 
The licensee obtained the source in 1994 and relied on the erroneous
 
source strength determination
 
during treatments.
 
Also, the source had not been decay-corrected
 
by either owner since 1990. NRC urged the licensee to have the eye applicator
 
recalibrated
 
and to be instructed
 
in the D Fc2 proper method to calculate
 
the decay of the source.The licensee subsequently
 
had the eye applicator
 
recalibrated
 
by the National Institute
 
of Standards
 
and Technology.
 
The resultant
 
recalibration
 
revealed a dose rate of 0.53 Gray (53 rad)/sec rather than the 0.24 Gy (24 rad)/sec used by the licensee.
 
The licensee had prescribed
 
a total dose of between 10 to 25 Gy (1000 to 2500 rad) for approximately
 
9-0709036 f arr&0 C. Dr Ilt, 2a
 
IN 96-66 December 13, 1996 70 patients, but actually administered
 
about twice this amount. An NRC medical consultant
 
has reviewed the cases and has recommended
 
that the patients be evaluated
 
for any adverse effects.Case 2. In November 1995, while reviewing
 
treatment
 
records during a routine NRC inspection
 
of a licensee authorized
 
to use a Sr-90 eye applicator
 
in Honolulu, Hawaii, an NRC inspector
 
determined
 
that the licensee had incorrectly
 
calculated
 
the decay of the strength of a Sr-90 eye applicator
 
and subsequently
 
delivered
 
doses 20 percent over the prescribed
 
doses to 16 patients.
 
The root cause of this event was the licensee improperly
 
calculating
 
the decay of the Sr-90 source. Specifically, the licensee linearly decayed the strength of the source instead of logarithmically
 
decaying the source strength of the eye applicator.
 
Before May 1995, a technologist
 
had correctly
 
calculated
 
the decay of the source; however, when this technologist
 
left, the physician
 
incorrectly
 
calculated
 
the source decay based on a linear decay from the previous calculations.
 
In addition, the incorrect
 
half-life
 
of Sr-90 was used in the calculation.
 
Following
 
a correct determination
 
of the source strength, the licensee determined
 
that 17 misadministrations
 
involving
 
16 patients occurred, from May 6, 1995 to November 16, 1995, including
 
one patient who was treated on both eyes. The delivered
 
doses range from 21.1 to 22.7 percent greater than the prescribed
 
dose of 40 Gy (4000 rad).Discussion
 
10 CFR 35.32, *Quality Management
 
Program," requires licensees
 
to develop written procedures
 
to meet five objectives
 
associated
 
with any brachytherapy
 
dose, including
 
assurance
 
that the prescribed
 
dose is the administered
 
dose.A necessary
 
part of this is to ensure that the dose rate emitted from an applicator
 
is correct. If the manufacturer's
 
certificate
 
of calibration
 
or original activity/dose
 
rate name plate is missing, the licensee should arrange with a qualified
 
expert to determine
 
the dose rate from the Sr-90 source.(For additional
 
details, see NRC IN 94-17, NSr-90 Eye Applicators:
Submission
 
of Quality Management
 
Plan, Calibration
 
and Use," dated March 11, 1994.)Failure to implement
 
the Quality Management
 
Rule and make required reports may subject a licensee to orders, civil penalties, and notices of violation.
 
In view of the nature of the cited events, it appears worthwhile
 
to review some of the properties
 
of Sr-90 eye applicators
 
and the related processes
 
for decay correction
 
over time. New Sr-90 eye applicators
 
typically
 
contain a 2 gigabecquerel (GBq) [54 millicurie(mCi)]
source, exhibiting
 
a surface dose rate of about 0.50 Gy (50 rad)/sec.
 
The half-life
 
of the parent Sr-90 is 28.5 yrs [maximum beta energy equal to 0.54 mega-electron
 
volts (MeY)], and the yttrium-90 (Y-90) daughter half-life
 
is 64.2 hrs (beta-max, 2.27 MeV);therefore, both isotopes are in equilibrium
 
on the eye applicator.
 
Since Sr-90 and Y-90 are in equilibrium, emissions
 
from both isotopes must be accounted
 
for in dosimetry
 
calculations.
 
IN 96-66 December 13, 1996 The dose rate (D,) at a time (t) can be calculated
 
from the initial dose rate (De) at the time of the most recent calibration
 
with the following
 
formula: D = D -(e-^t) (FI)where e, the base of the natural logarithm
 
(2.718), is raised to the power -Xt and is referred to as the 'decay factor' (df), where -X --0.693/Tx, T. is the half-life
 
of the isotope, and t is the elapsed time. For Sr-90, TX-28.5 years; therefore, X -(0.693)/(28.5 yrs) = 0.0243 yr'. The values for df can be used to determine
 
the fraction of original activity remaining
 
after t years. These values can then be used to calculate
 
dose rates by using the following
 
formula: D,= Dao df (F2)The fraction of activity remaining
 
after a given number of years from the original measurement
 
date is given in Table 1 (Attachment
 
1).For example An eye applicator
 
calibrated
 
by the manufacturer
 
on January 1, 1978, delivered an initial dose rate ( Do) of 0.75 Gy/sec (75 rad/sec) on contact. If, on January 1, 1996, the eye applicator
 
needs to be used, the elapsed time (in years) since calibration
 
is 18, and from Table 1, df = 0.646 for Sr-90.Using formula F2: D, = bo. df D18yaM -(0.75 Gy/sec)(0.646)
bigyea -0.485 Gy/sec (48.5 rad/sec)
IN 96-66 December 13, 1996 Table I may be extended using formula F1 and the value X -0.0243 yr' for Sr-90. Other values of df that need to be evaluated
 
by licensees
 
will need to be re-calculated
 
by using the appropriate
 
half-life
 
for that isotope.Alternatively, a semi-logarithmic
 
plot of the above data will yield a straight line, which may be extended beyond 25 years.This information
 
notice requires no specific action nor written response.
 
If you have any questions
 
about the information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
regional office.Donald A. Cool, D rector Division of Industrial
 
and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards
 
Technical
 
contacts:
Jose M. Diaz-Velez, RII (404) 331-7438 E-mail: jxd2@nrc.gov
 
Emilio M. Garcia, RIV (510) 975-0239 E-mail: emg@nrc.gov
 
James A. Smith, NMSS (301) 415-7904 E-mail: jas4@nrc.gov
 
Attachments:
1. List of Recently Issued NMSS Information
 
Notices 2. List of Recently Issued NRC Information
 
Notices 42 T7SS I (/4e
 
Attachment
 
I IN 96-66 December 13, 1996 Page 1 of I TABLE 1 FRACTION (EXPRESSED
 
AS DECIMAL) OF ORIGINAL SR-90 ACTIVITY REMAINING
 
AFTER (t) YEARS Years (t) df Years (t) df Years (t) df Years (t) df.25 0.994 6.5 0.854 12.75 0.734 19 0.63.5 0.988 6.75 0.849 13 0.729 19.25 0.626.75 0.982 7 0.844 13.25 0.725 19.5 0.623 1 0.976 7.25 0.838 13.5 0.72 19.75 0.619 1.25 0.97 7.5 0.833 13.75 0.716 20 0.615 1.5 0.964 7.75 0.828 14 0.712 20.25 0.611 1.75 0.958 8 0.823 14.25 0.707 20.5 0.608 2 0.953 8.25 0.818 14.5 0.703 20.75 0.604 2.25 0.947 8.5 0.813 14.75 0.699 21 0.6 2.5 0.941 8.75 0.808 15 0.695 21.25 0.597 2.75 0.935 9 0.804 15.25 0.69 21.5 0.593 3 0.93 9.25 0.799 15.5 0.686 21.75 0.589 3.25 0.924 9.5 0.794 15.75 0.682 22 0.586 3.5 0.918 9.75 0.789 16 0.678 22.25 0.582 3.75 0.913 10 0.784 16.25 0.674 22.5 0.579 4 0.907 10.25 0.78 16.5 0.67 22.75 0.575 4.25 0.902 10.5 0.775 16.75 0.666 23 0.572 4.5 0.896 10.75 0.77 17 0.662 23.25 0.568 4.75 0.891 11 0.765 17.25 0.658 23.5 0.565 5 0.886 11.25 0.761 17.5 0.654 23.75 0.562 5.25 0.88 11.5 0.756 17.75 0.65 24 0.558 5.5 0.875 11.75 0.752 18 0.646 24.25 0.555 5.75 0.87 12 0.747 18.25 0.642 24.5 0.551 6 0.864 12.25 0.743 18.5 0.638 24.75 0.548 6.25 0.859 12.5 0.738 18.75 0.634 25 0.545 Attachment
 
2 IN 96-66 December 13, 1996 Page 1 of I UST OF RECENTLY ISSUED NMSS INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 96-63 96-57 96-54 96-53 96-52 96-51 Potential
 
Safety Issue Regarding
 
the Shipment of Fissile Material Incident-Reporting
 
Require-ments Involving
 
Intakes, During a 24-Hour Period that May Cause a Total Effective
 
===Dose Equivalent===
in Excess of 0.05 Sv (5 rem)Vulnerability
 
of Stainless Steel to Corrosion
 
===When Sensitized===
Retrofit to Amersham 660 Posilock Radiography
 
Camera to Correct Incon-sistency in 10 CFR Part 34 Compatibility
 
Cracked Insertion
 
Rods on Troxler Model 3400 Series Portable Moisture Density Gauges Residual Contamination
 
Remaining
 
in Krypton-85 Handling System After Venting 12/05196 10/30196 10/17/96 10115/96 09/26/96 09/11196 All U.S. Nuclear Regulatory
 
Commission
 
licensees authorized
 
to possess special nuclear material in unsealed quantities
 
greater than a critical mass All U.S. Nuclear Regulatory
 
Commission
 
licensees All material licensees All industrial
 
radiography
 
licensees All U.S. Nuclear Regulatory
 
Commission
 
portable gauge licensees
 
and vendors All material licensees
 
' >Attachment
 
3 IN 96-66 December 13, 1996 Page 1 of I UST OF RECENTLY ISSUED NRC INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 96-65 96-64 96-63 96-62 96-61 96-60 Undetected
 
===Accumulation===
of Gas in Reactor Coolant System and Inaccurate
 
Reactor Water Level Indication
 
During Shutdown Modifications
 
to Con-tainment Blowout Panels Without Appropriate
 
Design Controls Potential
 
Safety Issue Regarding
 
the Shipment of Fissile Material Potential
 
Failure of the Instantaneous
 
Trip Function of General Electric RMS-9 Programmers
 
Failure of a Main Steam Safety Valve to Reseat Caused by an Improperly
 
Installed
 
Release Nut Potential
 
Common-Mode
 
Post-Accident Failure of Residual Heat Removal Heat Exchangers
 
1211 1/96 12/10196 12/05196 11120196 11/20/96 11/14/96 All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear reactors All U.S. Nuclear Regulatory
 
Commission
 
licensees
 
authorized
 
to possess special nuclear material in unsealed quantities
 
greater than a critical mass All holders of OLs and CPs for nuclear power plants All holders of OLs or CPs for nuclear power.reactors All holders of OLs or CPs for nuclear power reactors OL = Operating
 
License CP = Construction
 
Permit
 
IN 96-66.December 13, 1996 Table 1 may be extended using formula FH and the value x -0.0243 yr 1 for Sr-90. Other values of df that need to be evaluated
 
by licensees
 
will need to be re-calculated
 
by using the appropriate
 
half-life
 
for that isotope.Alternatively, a semi-logarithmic
 
plot of the above data will yield a straight line, which may be extended beyond 25 years.This information
 
notice requires no specific action nor written response.
 
If you have any questions
 
about the information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
regional office.Donald A. Cool, Director Division of Industrial
 
and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards
 
Technical
 
contacts: Jose M. Diaz-Velez, RII (404) 331-7438 E-mail: jxd2@nrc.gov
 
Emilio M. Garcia, RIV (510) 975-0239 E-mail: emg@nrc.gov
 
James A. Smith, NMSS (301) 415-7904 E-mail: jas4enrc.gov
 
Attachments:
1. List of Recently 2. List of Recently Issued NMSS Information
 
Notices Issued NRC Information
 
Notices Official Record Copy S:\Jsmith\imns5350.JAS
 
OFC IMAB I E IMAB lIMAB I IMOB I Tech Ed I KANE JASmith SLMerchant
 
LWCamper o JMPiccone
 
o EKraus o DATE 1 11/26/96 11/26/96 1 10/28/96 10/29/96 8/01/96 OFC J JE I OGC I DD/IMNS I D/IMNS I NAME JLiebermano
 
SATreby o FCCombso DACool DATE 08/07/96 1 1/07/96 11/12/96 I 11/29/96-COWVER E = COVER & Attachment
 
N -NO COPY o- See Previous Concurrence
 
eIN 96-##'J November .1996 Table 1 may be extended using formula F1 and the value A = 0.0243 yr" for Sr-90. Other values of df that need to be evaluated
 
by licensees
 
will need to be re-calculated
 
by using the appropriate
 
half-life
 
for that isotope.Alternatively, a semi-logarithmic
 
plot of the above data will yield a straight line, which may extended beyond 25 years.This information
 
notice requires no specific action nor written response.
 
If you have any questions
 
about the information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
regional office.Donald A. Cool, Director Division of Industrial
 
and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards
 
Contacts: Jose M. Diaz-Velez, RII (404) 331-7438 Internet:
JXD2@NRC.GOV
 
Emilio M. Garcia, RIV (510) 975-0239 Internet:
EMG@NRC.GOV
 
James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV
 
Attachments:
1. Table of decay factors 2. List of Recently Issue(3. List of Recently Issue(fffirial Rernrd COnY Svisr d NMSS Information
 
Notices d NRC Information
 
Notices nith\imns5350JAS
 
OFC IMAB lE IMAB lIMAB lIMOB j Tech Ed NAME JASmi SLM@f@I~nt
 
LWCamper o JMPiccone
 
o EKraus @DATE it /96 i 10/8/ 9 6 10/29/96 8/01/96 OFC OE I OGC DD/IMNS DlIMNS NAME JLieberman@
SATreby @ FCCombs@ _____ __ _ _l DATE 08/07/96 11/07/96 11/12/96 ///t11/96= COVER E = COVER & Attachment
 
N = NO COPY ?--See Previous Concurrence
 
N 96-Il-N ovember 91996 This information
 
notice requires no specific action nor written respons .If you have any questions
 
about the information
 
in this notice, please c tact one of the technical
 
contacts listed below or the appropriate
 
reglo 1 office.Donald A. Cool, Director, Division of Industrial
 
and Medical Nuclear Sa ty Office of Nuclear terial Safety and Safeguards
 
Contacts:
Jose M. Diaz-Velez, RI (404) 331-7438 Internet:
JXD2@NRC.GOV
 
Emilio M. Garcia, RIV (510) 975-0239 Internet:
EMG@NRC.GOV
 
James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV
 
Attachments:
1. Table of decay factors 2. List of Recently Issued NMS Information
 
Notices 3. List of Recently Issued MR Information
 
Notices Official Record Copy 5: \smitinins5350.JAS
 
OFC IMAB I E IMAB//1S IMAB I IMOB I Tech E NAME JASmithm SL e rc nt LWCamper o JMPiccone
 
a EKraus o DATE t/ /14/96 A/ 96 10/28/96 10/29/96 8/01/96 OFC OE l OGC DD/IMNS D/IMNS NAME JLiebermanq/
SATreby o FCCombso DACool DATE 08/07/9 11/07/96 11/12/96 / /96 C = COVER E M OVER h Attachment
 
N a NO COPY o- See Previous Concurrence
 
;. N 96-##a *-i ovember .1996 D 18year " (0.75 Gy/sec)(0.646)
blyrs, 0G 0.485 Gy/sec Table 1 may be extended using formula F1 and the value A 0.0243 yr-.Alternatively, a semi-logarithmic
 
plot of the above dat will yield a straight line, which may extended beyond 20 years.This information
 
notice requires no specific actio nor written response.
 
If you have any questions
 
about the information
 
in t s notice, please contact one of the technical
 
contacts listed below or t appropriate
 
regional office.Donald .Cool. Director Divis on of Industrial
 
and M ical Nuclear Safety Ofice of Nuclear Material Safety and Safeguards
 
Contacts:
Jose M. Diaz-Velez, (404) 331-7438 Internet:JMD2@NRC.
 
V Emilio M. Garci , RIV (510) 975-0239/Internet:EM
 
C.GOV James A. S ,th NMSS (301) 415- 904 Internet- AS4@NRC.GOV
 
Attachments:
1. List of Recent y Issued NMSS Information
 
Notices 2. List of Rece ly Issued NRC Information
 
Notices Official Recordo S:\jsmith\imns5350.JAS
 
OFC IMA E IMAB jI I I MOB I Tech Ed i NAME I ant LWCamper o JMPiccone
 
@ EKraus o DATE / /1196 le /6///96 10/28/96 10/29/96 8/01/96 OFC / OE I OGC DD/IMNS D/IMNS lAM JLiebermano
 
SATreby o FCCombso DACool D0/07/96 11/07/96 11/12/96 / /96 ,COVER E = COVER & Attachment
 
N = NO COPY @- See Previous Concurrence
 
N 96-ft<iovember
 
,1996 D (0.75 Gy/sec)(0.646)
.0.485 Gy/sec Table 1 may be etended using formula F1 and the value X -0.0243 yr 1.Alternatively, a mi-logarithmic
 
plot of the above data will yield a straight line, which may ext nded beyond 20 years.This information
 
noti requires no specific action nor written response.
 
If you have any questions
 
bout the information
 
in this notice, please contact (one of) the technical
 
c tact(s) listed below or the appropriate
 
regional office.Donald A. Cool, Director Division of Industrial
 
and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards
 
Contacts:
Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.GOY
 
Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOV
 
James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV
 
Attachments:
1. List of Recently Issued NMSS Information
 
Notices 2. List of Recently Issued NRC Information
 
Notices Official Record Copy S:\Jsmith\imns5350.JAS
 
\OFC qIMABiLW B IM4AB -IMOB l E\Tech Ed NAME JASm1 i SL chant LWCamper a JMPiccone
 
c EKraus o DATE I I 1/96 _ / j 10/28/96 10/29/96 8/01/96 OFC OE OGC DD/IMNS D/IMNS NAME JLiebermano
 
SATreby a F (Cm DACool DATE 08/07/96 11/07/96 / /96 C a COVER E a CUVLK & Attacnment
 
N = mU LUr1'u- aee rrevmuUs IA0ICUIIrCLM.
 
,N 96-##' "-'-6ctober
 
,1996 ble8.. -(0.75 Gy/sec)(0.646)
l 0.4 y/sec Table 1 may be extended using fo ula F1 and the value X -0.0243 yre.Alternatively, a semi-logarithmic
 
lot of the above data will yield a straight line, which may extended beyond 20 ars.This information
 
notice requires no sp ific action nor written response.
 
If you have any questions
 
about the in frma ion in this notice, please contact (one of) the technical
 
contact(s)
listed elow or the appropriate
 
regional office.Donald A. -ool, Director Division o Industrial
 
and Medical Ntclear Safety Office of N clear Material Safety and Safegu rds Contacts:
Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.
 
GOY Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOV
 
James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC .GOV Attachments:
1. List of Recently Issued NMSS Information
 
Notices 2. List of Recently Issued NRC Information
 
Notices Official Record Copy S:\Jsmithi\mns5350.JAS
 
\OFC IMAB AB IMAB I l IMOB l \l,Tech EdlNAME JASai R SUM nt LWCamper a JMPiccone
 
o EKraus o DATE / -J/ 10/28/96 10/29/96 8/01/96 OFC OE DD/IMNS D/IMNS KANE JLiebermano
 
S ireb NIL FCCombs DACool DATE 08/07/96 l/ /1/96 / /96 / /96 aCOVER E a COVER & Attachment
 
K = ND COPY o- See Previous Concurrence
 
\
C, 6 I< ~N 96-#t 4 October ,1996 We have Dlew. -(0.75 Gy/sec)(0.646)
Table I may be extended using formula FH and the value X -0.0243 yr 1.Alternatively, a semi-icgarithmic
 
plot of the above data will yield a straight line, which may extended be~yond 20 years.This information
 
notice requires no specific action nor written response.
 
If you have any questions
 
about the information
 
in this notice, please contact (one of) the technical
 
contact(s)
listed below or the appropriate
 
regional office.Donald A. Cool, Director Division of Industrial
 
and Medical Nuclear Safety Office cf Nuclear Material and Safrguards
 
Safety Contacts: Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.60V
 
Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOY
 
James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV
 
Attachments:
1. List 2. List Official of Recently of Recently Record CODY Issued NMSS Information
 
Notices Issued NRC Information
 
Notices SA:smithkimtns535GJAS


IN 96-66December 13, 1996 0 patients, but actually administered about twice this amount. An NRCmedical consultant has reviewed the cases and has recommended that thepatients be evaluated for any adverse effects.Case 2. In November 1995, while reviewing treatment records during a routineNRC inspection of a licensee authorized to use a Sr-90 eye applicator inHonolulu, Hawaii, an NRC inspector determined that the licensee hadincorrectly calculated the decay of the strength of a Sr-90 eye applicator andsubsequently delivered doses 20 percent over the prescribed doses to 16patients. The root cause of this event was the licensee improperlycalculating the decay of the Sr-90 source. Specifically, the licenseelinearly decayed the strength of the source instead of logarithmicallydecaying the source strength of the eye applicator. Before May 1995, atechnologist had correctly calculated the decay of the source; however, whenthis technologist left, the physician incorrectly calculated the source decaybased on a linear decay from the previous calculations. In addition, theincorrect half-life of Sr-90 was used in the calculation.Following a correct determination of the source strength, the licenseedetermined that 17 misadministrations involving 16 patients occurred, fromMay 6, 1995 to November 16, 1995, including one patient who was treated onboth eyes. The delivered doses range from 21.1 to 22.7 percent greater thanthe prescribed dose of 40 Gy (4000 rad).Discussion10 CFR 35.32, *Quality Management Program," requires licensees to developwritten procedures to meet five objectives associated with any brachytherapydose, including assurance that the prescribed dose is the administered dose.A necessary part of this is to ensure that the dose rate emitted from anapplicator is correct. If the manufacturer's certificate of calibration ororiginal activity/dose rate name plate is missing, the licensee should arrangewith a qualified expert to determine the dose rate from the Sr-90 source.(For additional details, see NRC IN 94-17, NSr-90 Eye Applicators: Submissionof Quality Management Plan, Calibration and Use," dated March 11, 1994.)Failure to implement the Quality Management Rule and make required reports maysubject a licensee to orders, civil penalties, and notices of violation.In view of the nature of the cited events, it appears worthwhile to reviewsome of the properties of Sr-90 eye applicators and the related processes fordecay correction over time. New Sr-90 eye applicators typically contain a2 gigabecquerel (GBq) [54 millicurie(mCi)] source, exhibiting a surface doserate of about 0.50 Gy (50 rad)/sec. The half-life of the parent Sr-90 is28.5 yrs [maximum beta energy equal to 0.54 mega-electron volts (MeY)], andthe yttrium-90 (Y-90) daughter half-life is 64.2 hrs (beta-max, 2.27 MeV);therefore, both isotopes are in equilibrium on the eye applicator. SinceSr-90 and Y-90 are in equilibrium, emissions from both isotopes must beaccounted for in dosimetry calculations.
OFC IMAB E IMAB Tech NAME JASmi S on rchant C rer EKraus o DATE It /1 /96 /96 96 /09 /96 8/01/96 OFC OE lOGC lDD/IMNS l D/IMNS l~KANE JLiebermano


IN 96-66December 13, 1996 The dose rate (D,) at a time (t) can be calculated from the initial dose rate(De) at the time of the most recent calibration with the following formula:D = D -(e-^t) (FI)where e, the base of the natural logarithm (2.718), is raised to the power -Xtand is referred to as the 'decay factor' (df), where -X --0.693/Tx, T. isthe half-life of the isotope, and t is the elapsed time. For Sr-90, TX-28.5years; therefore, X -(0.693)/(28.5 yrs) = 0.0243 yr'. The values for df canbe used to determine the fraction of original activity remaining after tyears. These values can then be used to calculate dose rates by using thefollowing formula:D,= Dao df (F2)The fraction of activity remaining after a given number of years from theoriginal measurement date is given in Table 1 (Attachment 1).For exampleAn eye applicator calibrated by the manufacturer on January 1, 1978, deliveredan initial dose rate ( Do) of 0.75 Gy/sec (75 rad/sec) on contact. If, onJanuary 1, 1996, the eye applicator needs to be used, the elapsed time (inyears) since calibration is 18, and from Table 1, df = 0.646 for Sr-90.Using formula F2:D, = bo. dfD18yaM -(0.75 Gy/sec)(0.646)bigyea -0.485 Gy/sec(48.5 rad/sec)
SATreby FCCombs DACool DATE 08/07/96 / /96 I /96 / /96:* COVER E a COVER & Attachment
IN 96-66December 13, 1996 Table I may be extended using formula F1 and the value X -0.0243 yr' forSr-90. Other values of df that need to be evaluated by licensees will need tobe re-calculated by using the appropriate half-life for that isotope.Alternatively, a semi-logarithmic plot of the above data will yield a straightline, which may be extended beyond 25 years.This information notice requires no specific action nor written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below or the appropriate regional office.Donald A. Cool, D rectorDivision of Industrial andMedical Nuclear SafetyOffice of Nuclear Material Safetyand SafeguardsTechnical contacts: Jose M. Diaz-Velez, RII(404) 331-7438E-mail: jxd2@nrc.govEmilio M. Garcia, RIV(510) 975-0239E-mail: emg@nrc.govJames A. Smith, NMSS(301) 415-7904E-mail: jas4@nrc.govAttachments:1. List of Recently Issued NMSS Information Notices2. List of Recently Issued NRC Information Notices42 T7SS I (/4e


Attachment IIN 96-66December 13, 1996Page 1 of ITABLE 1FRACTION (EXPRESSED AS DECIMAL) OF ORIGINALSR-90 ACTIVITY REMAINING AFTER (t) YEARSYears (t) df Years (t) df Years (t) df Years (t) df.25 0.994 6.5 0.854 12.75 0.734 19 0.63.5 0.988 6.75 0.849 13 0.729 19.25 0.626.75 0.982 7 0.844 13.25 0.725 19.5 0.6231 0.976 7.25 0.838 13.5 0.72 19.75 0.6191.25 0.97 7.5 0.833 13.75 0.716 20 0.6151.5 0.964 7.75 0.828 14 0.712 20.25 0.6111.75 0.958 8 0.823 14.25 0.707 20.5 0.6082 0.953 8.25 0.818 14.5 0.703 20.75 0.6042.25 0.947 8.5 0.813 14.75 0.699 21 0.62.5 0.941 8.75 0.808 15 0.695 21.25 0.5972.75 0.935 9 0.804 15.25 0.69 21.5 0.5933 0.93 9.25 0.799 15.5 0.686 21.75 0.5893.25 0.924 9.5 0.794 15.75 0.682 22 0.5863.5 0.918 9.75 0.789 16 0.678 22.25 0.5823.75 0.913 10 0.784 16.25 0.674 22.5 0.5794 0.907 10.25 0.78 16.5 0.67 22.75 0.5754.25 0.902 10.5 0.775 16.75 0.666 23 0.5724.5 0.896 10.75 0.77 17 0.662 23.25 0.5684.75 0.891 11 0.765 17.25 0.658 23.5 0.5655 0.886 11.25 0.761 17.5 0.654 23.75 0.5625.25 0.88 11.5 0.756 17.75 0.65 24 0.5585.5 0.875 11.75 0.752 18 0.646 24.25 0.5555.75 0.87 12 0.747 18.25 0.642 24.5 0.5516 0.864 12.25 0.743 18.5 0.638 24.75 0.5486.25 0.859 12.5 0.738 18.75 0.634 25 0.545 Attachment 2IN 96-66December 13, 1996Page 1 of IUST OF RECENTLY ISSUEDNMSS INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to96-6396-5796-5496-5396-5296-51Potential Safety IssueRegarding the Shipmentof Fissile MaterialIncident-Reporting Require-ments Involving Intakes,During a 24-Hour Periodthat May Cause a TotalEffective Dose Equivalentin Excess of 0.05 Sv (5 rem)Vulnerability of StainlessSteel to Corrosion WhenSensitizedRetrofit to Amersham 660Posilock RadiographyCamera to Correct Incon-sistency in 10 CFR Part 34CompatibilityCracked Insertion Rodson Troxler Model 3400Series Portable MoistureDensity GaugesResidual ContaminationRemaining in Krypton-85Handling System AfterVenting12/0519610/3019610/17/9610115/9609/26/9609/11196All U.S. Nuclear RegulatoryCommission licenseesauthorized to possess specialnuclear material in unsealedquantities greater than acritical massAll U.S. Nuclear RegulatoryCommission licenseesAll material licenseesAll industrial radiographylicenseesAll U.S. Nuclear RegulatoryCommission portable gaugelicensees and vendorsAll material licensees
N = NO COPY e- See Previous Concurrence


' >Attachment 3IN 96-66December 13, 1996Page 1 of IUST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to96-6596-6496-6396-6296-6196-60Undetected Accumulationof Gas in Reactor CoolantSystem and InaccurateReactor Water LevelIndication During ShutdownModifications to Con-tainment Blowout PanelsWithout AppropriateDesign ControlsPotential Safety IssueRegarding the Shipmentof Fissile MaterialPotential Failure of theInstantaneous Trip Functionof General Electric RMS-9ProgrammersFailure of a Main Steam SafetyValve to Reseat Caused by anImproperly Installed ReleaseNutPotential Common-Mode Post-Accident Failure of ResidualHeat Removal Heat Exchangers1211 1/9612/1019612/051961112019611/20/9611/14/96All holders of OLsor CPs for nuclearpower reactorsAll holders of OLsor CPs for nuclearreactorsAll U.S. NuclearRegulatory Commissionlicensees authorizedto possess specialnuclear material inunsealed quantitiesgreater than a criticalmassAll holders of OLsand CPs for nuclearpower plantsAll holders of OLs orCPs for nuclear power.reactorsAll holders of OLs orCPs for nuclear powerreactorsOL = Operating LicenseCP = Construction Permit
A 'IN 96-##August ,1996 This informat n not1ce requires no specific action nor written response.


IN 96-66.December 13, 996Table 1 may be extended using formula FH and the value x -0.0243 yr1 forSr-90. Other values of df that need to be evaluated by licensees will need tobe re-calculated by using the appropriate half-life for that isotope.Alternatively, a semi-logarithmic plot of the above data will yield a straightline, which may be extended beyond 25 years.This information notice requires no specific action nor written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below or the appropriate regional office.Donald A. Cool, DirectorDivision of Industrial andMedical Nuclear SafetyOffice of Nuclear Material Safetyand SafeguardsTechnical contacts:Jose M. Diaz-Velez, RII(404) 331-7438E-mail: jxd2@nrc.govEmilio M. Garcia, RIV(510) 975-0239E-mail: emg@nrc.govJames A. Smith, NMSS(301) 415-7904E-mail: jas4enrc.govAttachments:1. List of Recently2. List of RecentlyIssued NMSS Information NoticesIssued NRC Information NoticesOfficial Record Copy S:\Jsmith\imns5350.JASOFC IMAB I E IMAB lIMAB I IMOB I Tech Ed IKANE JASmith SLMerchant LWCamper o JMPiccone o EKraus oDATE 1 11/26/96 11/26/96 1 10/28/96 10/29/96 8/01/96OFC J JE I OGC I DD/IMNS I D/IMNS INAME JLiebermano SATreby o FCCombso DACoolDATE 08/07/96 1 1/07/96 11/12/96 I 11/29/96-COWVER E = COVER & Attachment N -NO COPY o- See Previous Concurrence
If you have any qu tions about the information


eIN 96-##'J November .1996 Table 1 may be extended using formula F1 and the value A = 0.0243 yr" forSr-90. Other values of df that need to be evaluated by licensees will need tobe re-calculated by using the appropriate half-life for that isotope.Alternatively, a semi-logarithmic plot of the above data will yield a straightline, which may extended beyond 25 years.This information notice requires no specific action nor written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below or the appropriate regional office.Donald A. Cool, DirectorDivision of Industrial andMedical Nuclear SafetyOffice of Nuclear Material Safetyand SafeguardsContacts:Jose M. Diaz-Velez, RII(404) 331-7438Internet: JXD2@NRC.GOVEmilio M. Garcia, RIV(510) 975-0239Internet: EMG@NRC.GOVJames A. Smith, NMSS(301) 415-7904Internet:JAS4@NRC.GOVAttachments:1. Table of decay factors2. List of Recently Issue(3. List of Recently Issue(fffirial Rernrd COnY Svisrd NMSS Information Noticesd NRC Information Noticesnith\imns5350JASOFC IMAB lE IMAB lIMAB lIMOB j Tech EdNAME JASmi SLM@f@I~nt LWCamper o JMPiccone o EKraus @DATE it /96 i 10/8/ 9 6 10/29/96 8/01/96OFC OE I OGC DD/IMNS DlIMNSNAME JLieberman@ SATreby @ FCCombs@ _____ __ _ _lDATE 08/07/96 11/07/96 11/12/96 ///t11/96= COVER E = COVER & Attachment N = NO COPY ?--See Previous Concurrence
in this notice, please contact (one of) the techn cal contact(s)
listed below or the appropriate


N 96-Il-N ovember 91996 This information notice requires no specific action nor written respons .Ifyou have any questions about the information in this notice, please c tactone of the technical contacts listed below or the appropriate reglo 1 office.Donald A. Cool, Director,Division of Industrial andMedical Nuclear Sa tyOffice of Nuclear terial Safetyand SafeguardsContacts: Jose M. Diaz-Velez, RI(404) 331-7438Internet: JXD2@NRC.GOVEmilio M. Garcia, RIV(510) 975-0239Internet: EMG@NRC.GOVJames A. Smith, NMSS(301) 415-7904Internet:JAS4@NRC.GOVAttachments:1. Table of decay factors2. List of Recently Issued NMS Information Notices3. List of Recently Issued MR Information NoticesOfficial Record Copy 5: \smitinins5350.JASOFC IMAB I E IMAB//1S IMAB I IMOB I Tech ENAME JASmithm SL e rc nt LWCamper o JMPiccone a EKraus oDATE t/ /14/96 A/ 96 10/28/96 10/29/96 8/01/96OFC OE l OGC DD/IMNS D/IMNSNAME JLiebermanq/ SATreby o FCCombso DACoolDATE 08/07/9 11/07/96 11/12/96 / /96C = COVER E M OVER h Attachment N a NO COPY o- See Previous Concurrence
regional office.Donald A. Cool, Director Division of Industrial


;. N 96-##a *-i ovember .1996 D18year " (0.75 Gy/sec)(0.646)blyrs, 0G 0.485 Gy/secTable 1 may be extended using formula F1 and the value A 0.0243 yr-.Alternatively, a semi-logarithmic plot of the above dat will yield a straightline, which may extended beyond 20 years.This information notice requires no specific actio nor written response. Ifyou have any questions about the information in t s notice, please contactone of the technical contacts listed below or t appropriate regional office.Donald .Cool. DirectorDivis on of Industrial andM ical Nuclear SafetyOfice of Nuclear Material Safetyand SafeguardsContacts: Jose M. Diaz-Velez,(404) 331-7438Internet:JMD2@NRC. VEmilio M. Garci , RIV(510) 975-0239/Internet:EM C.GOVJames A. S ,th NMSS(301) 415- 904Internet- AS4@NRC.GOVAttachments:1. List of Recent y Issued NMSS Information Notices2. List of Rece ly Issued NRC Information NoticesOfficial Recordo S:\jsmith\imns5350.JASOFC IMA E IMAB jI I I MOB I Tech Ed iNAME I ant LWCamper o JMPiccone @ EKraus oDATE / /1196 le /6///96 10/28/96 10/29/96 8/01/96OFC / OE I OGC DD/IMNS D/IMNS lAM JLiebermano SATreby o FCCombso DACoolD0/07/96 11/07/96 11/12/96 / /96,COVER E = COVER & Attachment N = NO COPY @- See Previous Concurrence
and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards


N 96-ft<iovember ,1996 D (0.75 Gy/sec)(0.646).0.485 Gy/secTable 1 may be etended using formula F1 and the value X -0.0243 yr1.Alternatively, a mi-logarithmic plot of the above data will yield a straightline, which may ext nded beyond 20 years.This information noti requires no specific action nor written response. Ifyou have any questions bout the information in this notice, please contact(one of) the technical c tact(s) listed below or the appropriate regionaloffice.Donald A. Cool, DirectorDivision of Industrial andMedical Nuclear SafetyOffice of Nuclear Material Safetyand SafeguardsContacts: Jose M. Diaz-Velez, RII(404) 331-7438Internet:JMD2@NRC.GOYEmilio M. Garcia, RIV(510) 975-0239Internet:EMG@NRC.GOVJames A. Smith, NMSS(301) 415-7904Internet:JAS4@NRC.GOVAttachments:1. List of Recently Issued NMSS Information Notices2. List of Recently Issued NRC Information NoticesOfficial Record Copy S:\Jsmith\imns5350.JAS \OFC qIMABiLW B IM4AB -IMOB l E\Tech EdNAME JASm1 i SL chant LWCamper a JMPiccone c EKraus oDATE I I 1/96 _ / j 10/28/96 10/29/96 8/01/96OFC OE OGC DD/IMNS D/IMNSNAME JLiebermano SATreby a F (Cm DACoolDATE 08/07/96 11/07/96 / /96C a COVER E a CUVLK & Attacnment N = mU LUr1'u- aee rrevmuUs IA0ICUIIrCLM.
Contacts:  
Jose M. Diaz-Velez, RII (404) 331-7438 Emilio M. Garcia, RIV (510) 975-0239 James A. Smith, NMSS (301) 415-7904 Attachments:
1. List of Recently Issued NMSS Information


,N 96-##' "-'-6ctober ,1996 ble8.. -(0.75 Gy/sec)(0.646)l 0.4 y/secTable 1 may be extended using fo ula F1 and the value X -0.0243 yre.Alternatively, a semi-logarithmic lot of the above data will yield a straightline, which may extended beyond 20 ars.This information notice requires no sp ific action nor written response. Ifyou have any questions about the in frma ion in this notice, please contact(one of) the technical contact(s) listed elow or the appropriate regionaloffice.Donald A. -ool, DirectorDivision o Industrial andMedical Ntclear SafetyOffice of N clear Material Safetyand Safegu rdsContacts: Jose M. Diaz-Velez, RII(404) 331-7438Internet:JMD2@NRC. GOYEmilio M. Garcia, RIV(510) 975-0239Internet:EMG@NRC.GOVJames A. Smith, NMSS(301) 415-7904Internet:JAS4@NRC .GOVAttachments:1. List of Recently Issued NMSS Information Notices2. List of Recently Issued NRC Information NoticesOfficial Record Copy S:\Jsmithi\mns5350.JAS \OFC IMAB AB IMAB I l IMOB l \l,Tech EdlNAME JASai R SUM nt LWCamper a JMPiccone o EKraus oDATE / -J/ 10/28/96 10/29/96 8/01/96OFC OE DD/IMNS D/IMNSKANE JLiebermano S ireb NIL FCCombs DACoolDATE 08/07/96 l/ /1/96 / /96 / /96aCOVER E a COVER & Attachment K = ND COPY o- See Previous Concurrence \
Notices 2. List of Recently Issued NRC Information
C, 6 I< ~N 96-#t4 October ,1996 We have Dlew. -(0.75 Gy/sec)(0.646)Table I may be extended using formula FH and the value X -0.0243 yr1.Alternatively, a semi-icgarithmic plot of the above data will yield a straightline, which may extended be~yond 20 years.This information notice requires no specific action nor written response. Ifyou have any questions about the information in this notice, please contact(one of) the technical contact(s) listed below or the appropriate regionaloffice.Donald A. Cool, DirectorDivision of Industrial andMedical Nuclear SafetyOffice cf Nuclear Materialand SafrguardsSafetyContacts:Jose M. Diaz-Velez, RII(404) 331-7438Internet:JMD2@NRC.60VEmilio M. Garcia, RIV(510) 975-0239Internet:EMG@NRC.GOYJames A. Smith, NMSS(301) 415-7904Internet:JAS4@NRC.GOVAttachments:1. List2. ListOfficialof Recentlyof RecentlyRecord CODYIssued NMSS Information NoticesIssued NRC Information NoticesSA:smithkimtns535GJASOFC IMAB E IMAB TechNAME JASmi S on rchant C rer EKraus oDATE It /1 /96 /96 96 /09 /96 8/01/96OFC OE lOGC lDD/IMNS l D/IMNS l~KANE JLiebermano SATreby FCCombs DACoolDATE 08/07/96 / /96 I /96 / /96:* COVER E a COVER & Attachment N = NO COPY e- See Previous Concurrence


A 'IN 96-##August ,1996 This informat n not1ce requires no specific action nor written response. Ifyou have any qu tions about the information in this notice, please contact(one of) the techn cal contact(s) listed below or the appropriate regionaloffice.Donald A. Cool, DirectorDivision of Industrial andMedical Nuclear SafetyOffice of Nuclear Material Safetyand SafeguardsContacts: Jose M. Diaz-Velez, RII(404) 331-7438Emilio M. Garcia, RIV(510) 975-0239James A. Smith, NMSS(301) 415-7904Attachments:1. List of Recently Issued NMSS Information Notices2. List of Recently Issued NRC Information NoticesOfficial Record Copy G:\imns5350.JAS , )OFC IMAB l E I OGC lTech EdNAME JASmi'W per SATreby EKraus aDATE *in /96 __ /________ \___96 / /96 8/01/96OFC \ lI I DD/IMNS l D/IMNS lNAME Q jeerman FCCombs DACoolDATE ___9_ / /96: w COVER 'E i. COVER & Attachment N = NO COPY o- See Previous Concurrence
Notices Official Record Copy G:\imns5350.JAS , )OFC IMAB l E I OGC lTech Ed NAME JASmi'W per SATreby EKraus a DATE *in /96 __ /________  
\___96 / /96 8/01/96 OFC \ lI I DD/IMNS l D/IMNS lNAME Q jeerman FCCombs DACool DATE ___9_ / /96: w COVER 'E i. COVER & Attachment


}}
N = NO COPY o- See Previous Concurrence}}


{{Information notice-Nav}}
{{Information notice-Nav}}

Revision as of 14:08, 31 August 2018

Recent Misadministrations Caused by Incorrect Calibrations of Strontium-90 Eye Applicators
ML031050494
Person / Time
Site: Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant  Entergy icon.png
Issue date: 12/13/1996
From: Cool D A
NRC/NMSS/IMNS
To:
References
IN-96-066, NUDOCS 9612090360
Download: ML031050494 (15)
v • d • e


UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS

WASHINGTON, D.C. 20555 December 13, 1996 NRC INFORMATION

NOTICE 96-66: RECENT MISADMINISTRATIONS

CAUSED BY INCORRECT

CALIBRATIONS

OF STRONTIUM-90

EYE APPLICATORS

Addressees

All U.S. Nuclear Regulatory

Commission

Medical Use Licensees

authorized

to use strontium-90 (Sr-90) eye applicators.

Purpose

The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to alert addressees

to recent misadministrations

caused by incorrect source strength determinations

of Sr-90 eye applicators.

It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, as appropriate, to avoid similar problems.

However, suggestions

contained

in this information

notice are not NRC requirements;

therefore, no specific action nor written response is required.DescriDtion

of Circumstances

The primary causes of two recent events have been problems with calibration

and calculation

of the dose rates from Sr-90 applicators.

As a result, the administered

doses were not within 20 percent of the prescribed

dose.Case 1. In October 1995, during an inspection

of a licensee authorized

to use a Sr-90 eye applicator

in Mayag~ez, Puerto Rico, it was determined

that the calibration

record for the licensee's

Sr-90 eye applicator

was missing. A previous owner of the source lost the original calibration

certificate, and his medical physics consultant

performed

a check of the source strength.

This check was performed

with an inappropriate

measurement

instrument

and resulted in an incorrect

determination

of the source strength as 0.24 Gray (Gy)/sec 0 (24 rad/sec).

The licensee obtained the source in 1994 and relied on the erroneous

source strength determination

during treatments.

Also, the source had not been decay-corrected

by either owner since 1990. NRC urged the licensee to have the eye applicator

recalibrated

and to be instructed

in the D Fc2 proper method to calculate

the decay of the source.The licensee subsequently

had the eye applicator

recalibrated

by the National Institute

of Standards

and Technology.

The resultant

recalibration

revealed a dose rate of 0.53 Gray (53 rad)/sec rather than the 0.24 Gy (24 rad)/sec used by the licensee.

The licensee had prescribed

a total dose of between 10 to 25 Gy (1000 to 2500 rad) for approximately

9-0709036 f arr&0 C. Dr Ilt, 2a

IN 96-66 December 13, 1996 70 patients, but actually administered

about twice this amount. An NRC medical consultant

has reviewed the cases and has recommended

that the patients be evaluated

for any adverse effects.Case 2. In November 1995, while reviewing

treatment

records during a routine NRC inspection

of a licensee authorized

to use a Sr-90 eye applicator

in Honolulu, Hawaii, an NRC inspector

determined

that the licensee had incorrectly

calculated

the decay of the strength of a Sr-90 eye applicator

and subsequently

delivered

doses 20 percent over the prescribed

doses to 16 patients.

The root cause of this event was the licensee improperly

calculating

the decay of the Sr-90 source. Specifically, the licensee linearly decayed the strength of the source instead of logarithmically

decaying the source strength of the eye applicator.

Before May 1995, a technologist

had correctly

calculated

the decay of the source; however, when this technologist

left, the physician

incorrectly

calculated

the source decay based on a linear decay from the previous calculations.

In addition, the incorrect

half-life

of Sr-90 was used in the calculation.

Following

a correct determination

of the source strength, the licensee determined

that 17 misadministrations

involving

16 patients occurred, from May 6, 1995 to November 16, 1995, including

one patient who was treated on both eyes. The delivered

doses range from 21.1 to 22.7 percent greater than the prescribed

dose of 40 Gy (4000 rad).Discussion

10 CFR 35.32, *Quality Management

Program," requires licensees

to develop written procedures

to meet five objectives

associated

with any brachytherapy

dose, including

assurance

that the prescribed

dose is the administered

dose.A necessary

part of this is to ensure that the dose rate emitted from an applicator

is correct. If the manufacturer's

certificate

of calibration

or original activity/dose

rate name plate is missing, the licensee should arrange with a qualified

expert to determine

the dose rate from the Sr-90 source.(For additional

details, see NRC IN 94-17, NSr-90 Eye Applicators:

Submission

of Quality Management

Plan, Calibration

and Use," dated March 11, 1994.)Failure to implement

the Quality Management

Rule and make required reports may subject a licensee to orders, civil penalties, and notices of violation.

In view of the nature of the cited events, it appears worthwhile

to review some of the properties

of Sr-90 eye applicators

and the related processes

for decay correction

over time. New Sr-90 eye applicators

typically

contain a 2 gigabecquerel (GBq) [54 millicurie(mCi)]

source, exhibiting

a surface dose rate of about 0.50 Gy (50 rad)/sec.

The half-life

of the parent Sr-90 is 28.5 yrs [maximum beta energy equal to 0.54 mega-electron

volts (MeY)], and the yttrium-90 (Y-90) daughter half-life

is 64.2 hrs (beta-max, 2.27 MeV);therefore, both isotopes are in equilibrium

on the eye applicator.

Since Sr-90 and Y-90 are in equilibrium, emissions

from both isotopes must be accounted

for in dosimetry

calculations.

IN 96-66 December 13, 1996 The dose rate (D,) at a time (t) can be calculated

from the initial dose rate (De) at the time of the most recent calibration

with the following

formula: D = D -(e-^t) (FI)where e, the base of the natural logarithm

(2.718), is raised to the power -Xt and is referred to as the 'decay factor' (df), where -X --0.693/Tx, T. is the half-life

of the isotope, and t is the elapsed time. For Sr-90, TX-28.5 years; therefore, X -(0.693)/(28.5 yrs) = 0.0243 yr'. The values for df can be used to determine

the fraction of original activity remaining

after t years. These values can then be used to calculate

dose rates by using the following

formula: D,= Dao df (F2)The fraction of activity remaining

after a given number of years from the original measurement

date is given in Table 1 (Attachment

1).For example An eye applicator

calibrated

by the manufacturer

on January 1, 1978, delivered an initial dose rate ( Do) of 0.75 Gy/sec (75 rad/sec) on contact. If, on January 1, 1996, the eye applicator

needs to be used, the elapsed time (in years) since calibration

is 18, and from Table 1, df = 0.646 for Sr-90.Using formula F2: D, = bo. df D18yaM -(0.75 Gy/sec)(0.646)

bigyea -0.485 Gy/sec (48.5 rad/sec)

IN 96-66 December 13, 1996 Table I may be extended using formula F1 and the value X -0.0243 yr' for Sr-90. Other values of df that need to be evaluated

by licensees

will need to be re-calculated

by using the appropriate

half-life

for that isotope.Alternatively, a semi-logarithmic

plot of the above data will yield a straight line, which may be extended beyond 25 years.This information

notice requires no specific action nor written response.

If you have any questions

about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

regional office.Donald A. Cool, D rector Division of Industrial

and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards

Technical

contacts:

Jose M. Diaz-Velez, RII (404) 331-7438 E-mail: jxd2@nrc.gov

Emilio M. Garcia, RIV (510) 975-0239 E-mail: emg@nrc.gov

James A. Smith, NMSS (301) 415-7904 E-mail: jas4@nrc.gov

Attachments:

1. List of Recently Issued NMSS Information

Notices 2. List of Recently Issued NRC Information

Notices 42 T7SS I (/4e

Attachment

I IN 96-66 December 13, 1996 Page 1 of I TABLE 1 FRACTION (EXPRESSED

AS DECIMAL) OF ORIGINAL SR-90 ACTIVITY REMAINING

AFTER (t) YEARS Years (t) df Years (t) df Years (t) df Years (t) df.25 0.994 6.5 0.854 12.75 0.734 19 0.63.5 0.988 6.75 0.849 13 0.729 19.25 0.626.75 0.982 7 0.844 13.25 0.725 19.5 0.623 1 0.976 7.25 0.838 13.5 0.72 19.75 0.619 1.25 0.97 7.5 0.833 13.75 0.716 20 0.615 1.5 0.964 7.75 0.828 14 0.712 20.25 0.611 1.75 0.958 8 0.823 14.25 0.707 20.5 0.608 2 0.953 8.25 0.818 14.5 0.703 20.75 0.604 2.25 0.947 8.5 0.813 14.75 0.699 21 0.6 2.5 0.941 8.75 0.808 15 0.695 21.25 0.597 2.75 0.935 9 0.804 15.25 0.69 21.5 0.593 3 0.93 9.25 0.799 15.5 0.686 21.75 0.589 3.25 0.924 9.5 0.794 15.75 0.682 22 0.586 3.5 0.918 9.75 0.789 16 0.678 22.25 0.582 3.75 0.913 10 0.784 16.25 0.674 22.5 0.579 4 0.907 10.25 0.78 16.5 0.67 22.75 0.575 4.25 0.902 10.5 0.775 16.75 0.666 23 0.572 4.5 0.896 10.75 0.77 17 0.662 23.25 0.568 4.75 0.891 11 0.765 17.25 0.658 23.5 0.565 5 0.886 11.25 0.761 17.5 0.654 23.75 0.562 5.25 0.88 11.5 0.756 17.75 0.65 24 0.558 5.5 0.875 11.75 0.752 18 0.646 24.25 0.555 5.75 0.87 12 0.747 18.25 0.642 24.5 0.551 6 0.864 12.25 0.743 18.5 0.638 24.75 0.548 6.25 0.859 12.5 0.738 18.75 0.634 25 0.545 Attachment

2 IN 96-66 December 13, 1996 Page 1 of I UST OF RECENTLY ISSUED NMSS INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 96-63 96-57 96-54 96-53 96-52 96-51 Potential

Safety Issue Regarding

the Shipment of Fissile Material Incident-Reporting

Require-ments Involving

Intakes, During a 24-Hour Period that May Cause a Total Effective

Dose Equivalent

in Excess of 0.05 Sv (5 rem)Vulnerability

of Stainless Steel to Corrosion

When Sensitized

Retrofit to Amersham 660 Posilock Radiography

Camera to Correct Incon-sistency in 10 CFR Part 34 Compatibility

Cracked Insertion

Rods on Troxler Model 3400 Series Portable Moisture Density Gauges Residual Contamination

Remaining

in Krypton-85 Handling System After Venting 12/05196 10/30196 10/17/96 10115/96 09/26/96 09/11196 All U.S. Nuclear Regulatory

Commission

licensees authorized

to possess special nuclear material in unsealed quantities

greater than a critical mass All U.S. Nuclear Regulatory

Commission

licensees All material licensees All industrial

radiography

licensees All U.S. Nuclear Regulatory

Commission

portable gauge licensees

and vendors All material licensees

' >Attachment

3 IN 96-66 December 13, 1996 Page 1 of I UST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 96-65 96-64 96-63 96-62 96-61 96-60 Undetected

Accumulation

of Gas in Reactor Coolant System and Inaccurate

Reactor Water Level Indication

During Shutdown Modifications

to Con-tainment Blowout Panels Without Appropriate

Design Controls Potential

Safety Issue Regarding

the Shipment of Fissile Material Potential

Failure of the Instantaneous

Trip Function of General Electric RMS-9 Programmers

Failure of a Main Steam Safety Valve to Reseat Caused by an Improperly

Installed

Release Nut Potential

Common-Mode

Post-Accident Failure of Residual Heat Removal Heat Exchangers

1211 1/96 12/10196 12/05196 11120196 11/20/96 11/14/96 All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear reactors All U.S. Nuclear Regulatory

Commission

licensees

authorized

to possess special nuclear material in unsealed quantities

greater than a critical mass All holders of OLs and CPs for nuclear power plants All holders of OLs or CPs for nuclear power.reactors All holders of OLs or CPs for nuclear power reactors OL = Operating

License CP = Construction

Permit

IN 96-66.December 13, 1996 Table 1 may be extended using formula FH and the value x -0.0243 yr 1 for Sr-90. Other values of df that need to be evaluated

by licensees

will need to be re-calculated

by using the appropriate

half-life

for that isotope.Alternatively, a semi-logarithmic

plot of the above data will yield a straight line, which may be extended beyond 25 years.This information

notice requires no specific action nor written response.

If you have any questions

about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

regional office.Donald A. Cool, Director Division of Industrial

and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards

Technical

contacts: Jose M. Diaz-Velez, RII (404) 331-7438 E-mail: jxd2@nrc.gov

Emilio M. Garcia, RIV (510) 975-0239 E-mail: emg@nrc.gov

James A. Smith, NMSS (301) 415-7904 E-mail: jas4enrc.gov

Attachments:

1. List of Recently 2. List of Recently Issued NMSS Information

Notices Issued NRC Information

Notices Official Record Copy S:\Jsmith\imns5350.JAS

OFC IMAB I E IMAB lIMAB I IMOB I Tech Ed I KANE JASmith SLMerchant

LWCamper o JMPiccone

o EKraus o DATE 1 11/26/96 11/26/96 1 10/28/96 10/29/96 8/01/96 OFC J JE I OGC I DD/IMNS I D/IMNS I NAME JLiebermano

SATreby o FCCombso DACool DATE 08/07/96 1 1/07/96 11/12/96 I 11/29/96-COWVER E = COVER & Attachment

N -NO COPY o- See Previous Concurrence

eIN 96-##'J November .1996 Table 1 may be extended using formula F1 and the value A = 0.0243 yr" for Sr-90. Other values of df that need to be evaluated

by licensees

will need to be re-calculated

by using the appropriate

half-life

for that isotope.Alternatively, a semi-logarithmic

plot of the above data will yield a straight line, which may extended beyond 25 years.This information

notice requires no specific action nor written response.

If you have any questions

about the information

in this notice, please contact one of the technical

contacts listed below or the appropriate

regional office.Donald A. Cool, Director Division of Industrial

and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards

Contacts: Jose M. Diaz-Velez, RII (404) 331-7438 Internet:

JXD2@NRC.GOV

Emilio M. Garcia, RIV (510) 975-0239 Internet:

EMG@NRC.GOV

James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV

Attachments:

1. Table of decay factors 2. List of Recently Issue(3. List of Recently Issue(fffirial Rernrd COnY Svisr d NMSS Information

Notices d NRC Information

Notices nith\imns5350JAS

OFC IMAB lE IMAB lIMAB lIMOB j Tech Ed NAME JASmi SLM@f@I~nt

LWCamper o JMPiccone

o EKraus @DATE it /96 i 10/8/ 9 6 10/29/96 8/01/96 OFC OE I OGC DD/IMNS DlIMNS NAME JLieberman@

SATreby @ FCCombs@ _____ __ _ _l DATE 08/07/96 11/07/96 11/12/96 ///t11/96= COVER E = COVER & Attachment

N = NO COPY ?--See Previous Concurrence

N 96-Il-N ovember 91996 This information

notice requires no specific action nor written respons .If you have any questions

about the information

in this notice, please c tact one of the technical

contacts listed below or the appropriate

reglo 1 office.Donald A. Cool, Director, Division of Industrial

and Medical Nuclear Sa ty Office of Nuclear terial Safety and Safeguards

Contacts:

Jose M. Diaz-Velez, RI (404) 331-7438 Internet:

JXD2@NRC.GOV

Emilio M. Garcia, RIV (510) 975-0239 Internet:

EMG@NRC.GOV

James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV

Attachments:

1. Table of decay factors 2. List of Recently Issued NMS Information

Notices 3. List of Recently Issued MR Information

Notices Official Record Copy 5: \smitinins5350.JAS

OFC IMAB I E IMAB//1S IMAB I IMOB I Tech E NAME JASmithm SL e rc nt LWCamper o JMPiccone

a EKraus o DATE t/ /14/96 A/ 96 10/28/96 10/29/96 8/01/96 OFC OE l OGC DD/IMNS D/IMNS NAME JLiebermanq/

SATreby o FCCombso DACool DATE 08/07/9 11/07/96 11/12/96 / /96 C = COVER E M OVER h Attachment

N a NO COPY o- See Previous Concurrence

. N 96-##a *-i ovember .1996 D 18year " (0.75 Gy/sec)(0.646)

blyrs, 0G 0.485 Gy/sec Table 1 may be extended using formula F1 and the value A 0.0243 yr-.Alternatively, a semi-logarithmic

plot of the above dat will yield a straight line, which may extended beyond 20 years.This information

notice requires no specific actio nor written response.

If you have any questions

about the information

in t s notice, please contact one of the technical

contacts listed below or t appropriate

regional office.Donald .Cool. Director Divis on of Industrial

and M ical Nuclear Safety Ofice of Nuclear Material Safety and Safeguards

Contacts:

Jose M. Diaz-Velez, (404) 331-7438 Internet:JMD2@NRC.

V Emilio M. Garci , RIV (510) 975-0239/Internet:EM

C.GOV James A. S ,th NMSS (301) 415- 904 Internet- AS4@NRC.GOV

Attachments:

1. List of Recent y Issued NMSS Information

Notices 2. List of Rece ly Issued NRC Information

Notices Official Recordo S:\jsmith\imns5350.JAS

OFC IMA E IMAB jI I I MOB I Tech Ed i NAME I ant LWCamper o JMPiccone

@ EKraus o DATE / /1196 le /6///96 10/28/96 10/29/96 8/01/96 OFC / OE I OGC DD/IMNS D/IMNS lAM JLiebermano

SATreby o FCCombso DACool D0/07/96 11/07/96 11/12/96 / /96 ,COVER E = COVER & Attachment

N = NO COPY @- See Previous Concurrence

N 96-ft<iovember

,1996 D (0.75 Gy/sec)(0.646)

.0.485 Gy/sec Table 1 may be etended using formula F1 and the value X -0.0243 yr 1.Alternatively, a mi-logarithmic

plot of the above data will yield a straight line, which may ext nded beyond 20 years.This information

noti requires no specific action nor written response.

If you have any questions

bout the information

in this notice, please contact (one of) the technical

c tact(s) listed below or the appropriate

regional office.Donald A. Cool, Director Division of Industrial

and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards

Contacts:

Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.GOY

Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOV

James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV

Attachments:

1. List of Recently Issued NMSS Information

Notices 2. List of Recently Issued NRC Information

Notices Official Record Copy S:\Jsmith\imns5350.JAS

\OFC qIMABiLW B IM4AB -IMOB l E\Tech Ed NAME JASm1 i SL chant LWCamper a JMPiccone

c EKraus o DATE I I 1/96 _ / j 10/28/96 10/29/96 8/01/96 OFC OE OGC DD/IMNS D/IMNS NAME JLiebermano

SATreby a F (Cm DACool DATE 08/07/96 11/07/96 / /96 C a COVER E a CUVLK & Attacnment

N = mU LUr1'u- aee rrevmuUs IA0ICUIIrCLM.

,N 96-##' "-'-6ctober

,1996 ble8.. -(0.75 Gy/sec)(0.646)

l 0.4 y/sec Table 1 may be extended using fo ula F1 and the value X -0.0243 yre.Alternatively, a semi-logarithmic

lot of the above data will yield a straight line, which may extended beyond 20 ars.This information

notice requires no sp ific action nor written response.

If you have any questions

about the in frma ion in this notice, please contact (one of) the technical

contact(s)

listed elow or the appropriate

regional office.Donald A. -ool, Director Division o Industrial

and Medical Ntclear Safety Office of N clear Material Safety and Safegu rds Contacts:

Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.

GOY Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOV

James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC .GOV Attachments:

1. List of Recently Issued NMSS Information

Notices 2. List of Recently Issued NRC Information

Notices Official Record Copy S:\Jsmithi\mns5350.JAS

\OFC IMAB AB IMAB I l IMOB l \l,Tech EdlNAME JASai R SUM nt LWCamper a JMPiccone

o EKraus o DATE / -J/ 10/28/96 10/29/96 8/01/96 OFC OE DD/IMNS D/IMNS KANE JLiebermano

S ireb NIL FCCombs DACool DATE 08/07/96 l/ /1/96 / /96 / /96 aCOVER E a COVER & Attachment

K = ND COPY o- See Previous Concurrence

\

C, 6 I< ~N 96-#t 4 October ,1996 We have Dlew. -(0.75 Gy/sec)(0.646)

Table I may be extended using formula FH and the value X -0.0243 yr 1.Alternatively, a semi-icgarithmic

plot of the above data will yield a straight line, which may extended be~yond 20 years.This information

notice requires no specific action nor written response.

If you have any questions

about the information

in this notice, please contact (one of) the technical

contact(s)

listed below or the appropriate

regional office.Donald A. Cool, Director Division of Industrial

and Medical Nuclear Safety Office cf Nuclear Material and Safrguards

Safety Contacts: Jose M. Diaz-Velez, RII (404) 331-7438 Internet:JMD2@NRC.60V

Emilio M. Garcia, RIV (510) 975-0239 Internet:EMG@NRC.GOY

James A. Smith, NMSS (301) 415-7904 Internet:JAS4@NRC.GOV

Attachments:

1. List 2. List Official of Recently of Recently Record CODY Issued NMSS Information

Notices Issued NRC Information

Notices SA:smithkimtns535GJAS

OFC IMAB E IMAB Tech NAME JASmi S on rchant C rer EKraus o DATE It /1 /96 /96 96 /09 /96 8/01/96 OFC OE lOGC lDD/IMNS l D/IMNS l~KANE JLiebermano

SATreby FCCombs DACool DATE 08/07/96 / /96 I /96 / /96:* COVER E a COVER & Attachment

N = NO COPY e- See Previous Concurrence

A 'IN 96-##August ,1996 This informat n not1ce requires no specific action nor written response.

If you have any qu tions about the information

in this notice, please contact (one of) the techn cal contact(s)

listed below or the appropriate

regional office.Donald A. Cool, Director Division of Industrial

and Medical Nuclear Safety Office of Nuclear Material Safety and Safeguards

Contacts:

Jose M. Diaz-Velez, RII (404) 331-7438 Emilio M. Garcia, RIV (510) 975-0239 James A. Smith, NMSS (301) 415-7904 Attachments:

1. List of Recently Issued NMSS Information

Notices 2. List of Recently Issued NRC Information

Notices Official Record Copy G:\imns5350.JAS , )OFC IMAB l E I OGC lTech Ed NAME JASmi'W per SATreby EKraus a DATE *in /96 __ /________

\___96 / /96 8/01/96 OFC \ lI I DD/IMNS l D/IMNS lNAME Q jeerman FCCombs DACool DATE ___9_ / /96: w COVER 'E i. COVER & Attachment

N = NO COPY o- See Previous Concurrence


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