ML20100K680

From kanterella
Jump to navigation Jump to search

Responds to Request for Addl Info Dtd 960212.Author Will Address Item in Order Listed in Request
ML20100K680
Person / Time
Site: Washington State University
Issue date: 02/23/1996
From: Tripard G
WASHINGTON STATE UNIV., PULLMAN, WA
To: Mendonca M
NRC
References
TAC-M79607, NUDOCS 9603010240
Download: ML20100K680 (15)


Text

..

F

{ WashingtonStateUniversity M Nuclear Radiation Center Pullman, WA 99164-1300 509-335-8641 FAX SO9-335 4433 Friday, February 23,1996 Marvin M. Mendonca Senior Project Manager U.S. Nuclear Regulatory Commission MS OWFN 11-B-20 Washington, D.C. 20555 Ref: Docket 50-27 l

Dear Mr. Mendonca:

This letter is in response to a request for additional information (TAC NO. M79607) dated February 12,1996. I will address each item in the order in which they are listed in the request,

a. Installation of an automatic reactor scram and movement of the bridge as a response to an inadvenent or emergency entry into the treatment room, Answer: Tech. Spec 3.15,5(b) will be changed to read:

(b) The reactor shall scram and the bridge shall move to the retracted position automatically upon opening the treatment room's shield door.

b. Periodic surveillance testing for the automatic scram,  ;

1 Answer: Tech. Spec 3.15,12(c) will be changed to read: '

l (c) Upon opening the treatment room's shield door Operational test j the reactor scrams and the bridge moves to the  ;

i retracted position

c. Periodic surveillance testing for the measurement of the reduction in gamma and neutron dose at

. the irradiation location due to bridge motion.

Answer: Tech. Spec 3.15,14(d) will be added. It will read:

(d) A scram from full power initiated when the reacta 's positioned against the medical facility filter shall be performed every six month . in the event of a design modification. The treatment room radiation moma reading shall not exceed 50 mR/hr, 30 seconds after the scram.  ;

O 010P59 9603010240 960223 7 DR ADOCK 0500 1 )}

i

. -. -- - _ _- -= . - . - - - - .- - . - -, . .-

Funher thought on the radiation safety aspects of this new facility have caused us to propose an additional feature in the interlocks. We would like to include an interlock that we will refer to as a

" medical facility lockdown key." The purpose of this key is to enable someone to enter the medical 1

facility area holding this key with the assurance that no one can turn on the reactor while he/she is in them. 'Ihe lockdown will be located next to the shield door. A person wishing to assure that the mactor can not be turned on simply removes the key from the lock and takes it with him/her. This safety featum could be partly accomplished by leaving the shield door open when working in the medical facility but it would not pmvent a second person from closing the door and then later starting up the reactor. We would therefom like to add the following two items:

Tech. Spec 3.15,5(f) will read: <

(f) A medical facility lockdown near the shield door shall inhibit blade withdrawal when the key is not inserted and turned to the locked position Tech Spec 3.15,12(k) will read:

(k) Medical facility lockdown blade inhibit Operational test We also made the cosmetic change of " certified medical physicist" to " medical use licensee" on page 1 in order to be consistent with earlier terminology.

Please find enclosed the third draft of changes we are proposing to our WSU reactor Technical Specifications in order to provide a medical therapy beam. We have placed side bars next to those items that differ slightly from the second draft.

Sincerely,

/ YY j bd' Gerald E. Tripard Dimetor enclosure: Draft-3 of the Proposed Technical Specification Ganges to Accommodate a Medical Therapy Facility at Washington State University cc: R. H. Filby, WSU J. M. Ryskamp, INEL D.W. Nigg, INEL R.J. Wiersema, Ionix W.R. Rayburn, WSU P.R. Gavin, WSU 1

3.15 GENERATION OF MEDICAL THERAPY FACILITY BEAM FOR HUMAN THERAPY Applicability l This specification applies solely to the generation of the medical therapy facility beam for the treatment of human patients. It does not apply to any other use of the medical therapy facility and/or its beam. Surveillances listed in this specification are only requited if human therapy is  ;

planned for the interval of the surveillance. However,in the event of a hiatus in the scheduled performance of any given surveillance, that surveillance shall be performed prior to the initiation of human therapy during the interval in question.

Obiective To provide for the pmtection of the public health and safety by ensuring that patients are i tmated in accordance with the tmatment plan established by the physician authorized user and that j l

the ALARA principle is observed for all non-therapeutic radiation exposums.  ;

Snecification

1. Patients accepted for treatment shall have been refermd by written directive from a physician authorized user of NRC Medical Use Licensee No. 20-03857-06 or of any other medical use licensee that has been similarly authorized by NRC to utilize the WSU Research Reactor's Medical Therapy Facility beam for neutron capture therapy for humans.
2. All medical treatments, including irradiations and analyses of the neutron capture agents in the patients, are the responsibility of the physician authorized user in charge of the therapy and the medical physicists from the NRC-licensed medical center. Washington State University is only responsible for providing curmnt and accurate beam characteristic parameters to the medical use licensee and for delivery of the desired radiation fluence as i requested in the written directive. Before the start of a therapy, both the medical use licensee and the Director of the Nuclear Radiation Center, or his designate, must agree that the therapy can be initiated. The physician authorized user is responsible for monitoring 1

l the therapy and for directing its termination. However, a radiation therapy can also be  !

terminated at any time if either the physician authorized user or the facility Director, or their designates, judge that the therapy should be terminated.

3. It shall be possible to initiate a scram of the reactor from a control panel located in the medical therapy facility area. In the event that the nvxlical facility scram is inoperable, it i shall be acceptable to use one of the control room scrams via communication with the

, mactor operator as a temporary means of satisfying this provision. Use of this temporary provision is limited to seven consecutive working days.

4. Access to the medical therapy facility shall be controlled by means of the shield door l

located at its entrance.

l S. 'Ihe following features and/or interlocks shall be operable:

(a) An interlock shall prevent moving the bridge from the retracted position unless the medical therapy facility's shield door is closed. ,

t (b) The reactor shall scram and the bridge shall move to the retracted position l l l automatically upon opening the treatment room's shield door.

i (c) 'Ihe bridge shall be designed to move to the retracted position automatically upon  ;

a failure of facility electric power or low voltage on the backup batteries that power the bridge motor.  !

(d) Bridge movemer.t that controls beam delivery shall be designed for manual 3

movement to the retracted position.

, (e) It shall be possible to move the bridge to the retracted position fmm within the l

! medical therapy facility.

l

!- (f) A medical facility lockdown near the shield door shall inhibit blade withdrawal when i i- i j~ the key is not inserted and turned to the locked position.

6. Bridge shall be equipped with a position readout that indicates the status of the bridge. A i

}-

( bridge position readout shall be visible at the medical therapy facility's local control panel, t

] In the event of a bridge position readout malfunction, it shall be acceptable to use an l i

i

}

l 2 i

1 . _ - _ _ _ . _ ___

alternate means of verifying position such as a video camera in the pool room providing a signal to a monitor at the medical therapy facility's local control panel. Use of this alternate means of bridge position verification is limited to seven consecutive working days.

7. The medical therapy facility shall be equipped with a monitor that provides a visual indication of the radiation level within the facility, that indicates both within the facility and at the local control panel, and that provides an audible Jarm both within the facility and at the local controlpanel.

(a) This radiation monitor shall be equipped with a backup power supply such as the reactor emergency power system or a battery.

(b) This radiation monitor shall be checked for proper operation by means of a check sourte on the calendar day of and prior to any patient irradiation.

(c) This radiation monitor shall be calibrated quarterly.

(d) The audible alarm shall be set at or below 50 mR/hr. This monitor and/or its alarm may be disabled once the medical therapy room has been searched and secured, such as is done immediately prior to initiation of patient therapy. If this is done, the monitor and/or its alarm shall be interlocked so that they become functional upon opening of the medical therapy facility shield door.

l (e) In the event that this monitor is inoperable, personnel entering the medical therapy 1

j facility shall use either portable survey instruments or audible alarm personal dosimeters as a temporary means of satisfying this provision. These instruments / dosimeters shall be in calibration as defined by the WSU Research l

! Reactor's radiation protection program and shall be source-checked daily prior to use

on any day that they are used to satisfy this provision. Use of these instruments / dosimeters as a temporary means of satisfying this provision is limited to
seven consecutive working days.
8. An intercom or other means of two-way communication shall be operable both between the medical therapy facility control panel and the reactor control room, and also between the a

3 i

medical therapy facility control panel and the interior of the facility. This latter is for the monitoring of patients. i

9. It shall be possible for personnel monitoring a patient to open the mulical therapy facility l shield door manually.  !
10. It shall be possible to observe the patient by means of two independent closed-circuit TV cameras. Both cameras providing patient visualization shall be operable at the outset of any 1 patient irradiation. Should either fail during the irradiation, the treatment may be continued at the disemtion of the physician' authorized user. Adequate lighting to permit such viewing i

shall be assured by the provision of emergency lighting.

I 1. The total radiation fluence delivered by the medical therapy facility beam as measured by on-line beam monitors shall not exceed that prescribed in the patient treatment plan by more than 20%. The tmatment is normally delivered in fractions in accordance with standard practice for human therapy. The 20% criterion applies to the sum of the radiation fluences l associated with all fractions in a given tmatment plan. A criterion of 30% applies to the 4 1

difference between the administemd and pmscribed fluence for any given week (seven consecutive days). Finally,if the treatment consists of three or fewer fractions, then a criterion of 10% shall apply.

12. The following interlocks or channels shall be tested at least monthly and prior to treatment of human patients if the interlock or channel has been repaired or deenergized:

Interlock or Channel Surveillance l

a) Medical therapy facility scram Scram test j i

i b) Bridge will not move from the retracted Operational test position w. iield dooris closed c) - Upon oputing the treatment room's shield Operational test door the reactor scrams and the bridge moves to the retracted position d) The bridge moves toward the retracted Operational test 4

l

- . . . ~ , . _ . . - - . . . . - - _ . _ , . , , _ ~ . ~. _. _ ,

I l

position on loss of electrical power j and low voltage on the bridge motor batteries e) Manual movement of bridge Operational test f) Bridge can be moved manually Operational test from within the facility g) Bridge position indicator and status Operational test lights h) Radiation monitor alarm Operational test i) Radiation monitor and/or alarm Operational test enabled upon opening of shield door j) Intercoms Operational test I

k) Medical facility lockdown blade inhibit Operational test In addition to the above, the medical therapy facility scram shall be tested prior to reactor l

startup if the reactor has been shut down for more than sixteen hours. I l

13. Manual operation of the medical therapy facility's shield door in which the door is opened i fully shall be verified semi-annually. )
14. Use of the medical therapy facility beam shall be subject to the following:

a) A calibration check of the beam and a functional check of the beam monitors that are described in provision 11 of this specification shall be made weekly for any week

that the beam will be used for human therapy. These checks shall be made prior to any pa
ient irradiation for a given week. In addition, a calibration check shall be performed prior to any patierit irradiation in the event that any component of a given l

beam design has been replaced. Fmally, a calibration and a functional check shall be performed prior to any patient irradiation in the event of a design modification, b) A characterization of the beam shall be performed every six months for any six-month interval that the beam will be used for human therapy. This six-month 5

characterization shall be made prior to any patient irradiation for a given six-month interval. A characterization shall also be performed prior to any patient irradiation in the event of a design modification. As part of the characterization process, the proper response of the beam monitors that are described in provision 11 of this specification shall be verified.

c) A calibration of the beam monitors that are described in provision 11 of this specification shall be performed at least once every two years for any two-year interval that the beam will be used for human therapy. The two-year calibration shall be made prior to any patient irradiation during any given two-year interval. ,

d) A scram from full power initiated when the reactor is positioned against the medical facility filter shall be performed every six months or in the event of a design modification. De treatment room radiation monitor reading shall not exceed 50 mR/hr,30 seconds after the scram.

15. Maintenance, repair, and modification of the medical therapy facility shall be performed under the supervision of a senior reactor operator who is licensed by the U.S. Nuclear Regulatory Commission to operate the WSU Research Reactor. The ' medical therapy I facility' includes the beam, bridge moving system, beam monitoring equipment, medical therapy facility shielding, shield door, and patient viewing equipment. All modifications will be reviewed pursuant to the requirements of 10 CFR 50.59. The operating couch,  :

i patient positioning equipment, medical instruments, and other equipment used for the direct medical support of the patient are not considered part of the medical therapy facility for  !

purposes of this provision, except insofar as radiation safety (i.e., activation and/or contandnation)is concerned.

16. Personnel who are not licensed to operate the WSU Research Reactor but who are responsible for either the medical therapy or the beam's design including construction

, and/or modification may operate the controls for the medical therapy facility beam provided that: .

6

-. ,i

~ - _ _ . - -. . - - . - - . . . - - . _ - --

(a) Training has been providal and proficiency satisfactorily demonstrated on the design of the facility, its controls, and the use of those controls. Proficiency shall be demonstrated annually.

(b) Instructions are posted at the medical therapy facility's local control panel that specify the procedure to be followed:

(i) to ensure that only the patient is in the treatment room before turning the primary beam of radiation on to begin a treatment; (ii) if the operator is unable to turn the primary beam of radiation off with controls outside the medical therapy facility, or if any other abnormal condition occurs. A directive shall be included with these instructions to notify the reactor console operator in the event of any abnormality.

(c) In the event that bridge movement affects reactivity, personnel who are not licensed on the WSU Research Reactor but who have been trained under this provision may initiate bridge movement provided that verbal permission is requested and received from the reactor console operator immediately prior to such action. Emergency l

l closures are e.n exception and may be made without first requesting permission.

l l Records of the training provided under subparagraph (a) above shall be retained in l

accordance with the WSU Research Reactor's training program or at least for three years.

A list of personnel so qualified shall be maintained in the reactor control room.

17. Events defined as ' recordable' under definition 8 of this specification shall be recorded and i
- the record maintained for five years. Events defined as 'misadminstrations' under i

definition 9 of this specification shall be reported to the U.S. Nuclear Regulatory l

Commission (24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> verbal,15 day written report). The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> verbal repons will be i I

made to the Regional Administrator, Region IV, or his designate. The 15 day written repons will be sent to the NRC Document Control Desk with a copy to the Regional Administration, Region IV or his designate. ,

7

p _ _ .. _ _ . _ _ _ _ _ . _ _ . _ _ . . _ _ _ . . _ _ _ _ - . _ .

1 i

18. The requirements of the Quality Management Program (QMP) for the Generation of Medical Therapy Facility Beam for Human Therapy at Washington State University i i

, _ Research Reactor shall be observed for any human therapy. (Holg: The presence of this j commitment to observe the QMP in these specifications does not preclude modifying the QMP as provided in that document. Any such modifications are not considered to be a change to the WSU Reactor Technical Specifications.)

Definitions

1. The medical therapy facility is equipped with a bridge moving system that is used to control beam delivery. Bridge movement analyses shall be documented through the standard safety review process including, where appropriate, an S AR revision and submission to NRC under 10 CFR 50.59.
2. The term ' calibration check' refers to the process of checking the beam intensity and quality  ;

via- r more of the following: foil activation; use of a fission chamber, use of an ion chamber, or an equivalent process. De purpose of a calibration check is to ensure that the l beam has not changed in a significant way (e.g., energy spectrum or intensity) from the beam that was characterized. j

3. The term ' functional check of the beam monitors' shall consist of verifying that system l l

output is consistent (i 19%) with previously measured values upon normalization to a common reactor neutronic power level.

4. The term ' characterization' refers to the process of obtaining the dose-versus-depth profile in phantoms. The dose-versus depth profile from the surface of the phantom to a depth at l least equivalent to the total thickness of the body part to be tirated on a central axis is l

\

l deemed adequate for a characterization. Fast neutron, thermal neutron, and gamma ray components are determined in a characterization and monitors are normalized by this l l characterization.

l 5

l

. i 8

- . . .. - .- ~ ~ _ - . _ _. . - _ _ -. - ..- -

i

. I

, 4

5. The term ' calibration of the beam monitors' refers to the process whereby the beam monitors that are described in provision 11 of this specification are calibrated against instruments that measure dese including a tissue equivalent chamber and a graphite or magnesium wall ionization chamber ( or the equivalent to any of these three) that have in  ;

turn been calibrated by a secondary calibration laboratory.

6. The term ' design modification' as applied to the medical therapy facility beam refers (a) to a change that is shown to alter the dose-versus-depth profile of the fast neutrons, thermal s

neutrons, or gamma rays in the beam as sensed by the calibration check and (b) to a change that has the potential to incmase significantly the amount of activation products in the ,

medical therapy facility when the beam is to be used for the treatment of human patients. ,

7. The term ' radiation fluence' means the total fluence of neutrons and gamma radiation that is j emitted in the medical therapy facility beam. The determination of the ratios of gamma, fast .

l neutron, and thermal neutron fluences is part of the beam characterization. Knowledge of I

these ratios allows the total radiation fluence to be monitored by the on-line detectors, which are neutron sensitive. Compliance with the limits specified on radiation fluence by this specification is determined by reference to the fluence monitored by these detectors. i 11 . The term 'mcordable event' means the administration of:

i (a) A radiation treatment without a written directive; or

(b) A radiation treatment where a written directive is mquired without reporting to the medical use licensee in writing each fluence given within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the treatment; l or (c) A treatment delivery for which the administered radiation fluence for any given fraction is 15% greater than prescribed.
9. The term ' misadministration' means the administration of a radiation therapy:

(a) Involving the wrong patient, wrong mode of treatment, or wrong tmatment site; or (b) When the delivery is not in accordance with provision 11 of this specification.

l 9

I

10. The term ' written directive' means an order in writing for a specific patient, dated and signed by a physician authorized user prior to the administration of radiation and which specifies the treatment site, the total adiation fluence, radiation fluence per fraction, and overall tmatment period.

I 1. The term ' human therapy' means radiation treatments that are of direct therapeutic benefit to the patient and/or part of investigatory studies that involve humans.

12. He term ' physician authorized user' means a medical physician approved for neutron capture therapy by an NRC-approved medical use licensee.
13. The term ' certified medical physicist' means a medical physicist certified in either radiological physics or therapeutic radiation physics by the American Board of Radiology, or in therapeutic radiation physics by the American Board of Medical Physics and who also has specific training in neutron dosimetry and neutron beam capture therapy.

Basis The stipulation that patients only be accepted from NRC Medical Use Licensee No. 20-03857-06 or from any other medical use licensee that has been similarly authorized by NRC to utilize the WSU Research Reactor's Medical Therapy Facility beam for human therapy, ensures that medical criteria imposed by NRC on such licensees for the use of the WSU Research Reactor's medical therapy facility beam for human therapy will be fulfilled. The second provision delineates the division of msponsibilities between Washington State University and the medical licensee that refers the patient. Also, it establishes administrative authority and protocol for initiating and terminating a radiation therapy.

The requirement that it be possible to initiate a scram from a control panel located in the medical therapy facility area assures the attending physician and/or medical physicist of the capability to terminate the tmatment immediately should the need arise. The provision that access to the medical therapy facility be limited to a single door ensures that there will be no inadvertent entries. The various interlocks for the bridge movement system that controls beam delivery ensure 10

, e.

~

that exposure levels in the medical therapy facility will be minimal prior to entry by personnel who are attending the patient. The bridge position indicator and status lights serve to notify personnel of the beam's status. The provision for a radiation monitor ensums that personnel will have information available on radiation levels in the medical therapy facility prior to entry. The purpose ,

1 of this monitor's audible alarm is to alert personnel to the presence of elevated radiation levels, j such as exist when the shuners that control beam delivery are open. This monitor and/or its alarm {

4 may be disabled once the medical therapy facility has been searched and secured so that it will (1) not disturb a l tient and (2) not distract attending personnel. The monitor and/or its alami are interlocked with the shield door so that they are made functional upon opening that door, and hence prior to any possible entry to the medical therapy facility. One intercom provides a means for the  :

prompt exchange of information between medical personnel and the reactor operator (s). The second intercom is for monitoring the patient.

The provision for manual operation of the medical therapy facility's shield door ensures

~

access to any patient in the event of a loss of electrical power. The presence of the closed-circuit TV cameras provide the attending physician authorized user and/or medical physicist with the opportunity to monitor the patient visually as well as through the use of various instruments. The

. viewing window will function even during an electric power failure because of the provision for emergency lighting.

The specification that the total radiation fluence for a therapy (i.e., the radiation fluences for the sum of all fractions specified in a given treatment plan) not exceed that prescribed in the patient treatment plan by 20% establishes a trigger limit on the delivered fluence above which the NRC has to be notified of a misadministration. The 20% criterion is based on the definition of misadministration (clause 4(iv)) as given in 10 CFR 35.2. The criterion that the diffen nce between the administered and prescribed fluence for any seven consecutive days is set at 30%.

This is also in accordance with the definition of misadministration (clause 4(iii)) as given in 10 l i

CFR 35.2. Finally, if a treatment involves three or fewer fractions, then a more stnngent entenon, 10%, applies to the difference between the total radiation fluence for a therapy and that prescribed 11

in the treatment plan (10 CFR 35.2(4ii)). The surveillance requirements for beam calibration checks and characterizations provide a mechanism for ensuring that the medical therapy facility and  ;

. its beam will perform as originally designed. Similarly, the surveillance requirements on the beam monitors ensure that these instruments are calibrated by a means traceable to the National Institute of Standards and Technology. The chambers specified (tissue-equivalent, and graphite or magnesium-wall) were chosen because they measum dose as opposed to fluence.

The specifications on maintenance and repair of the medical therapy facility ensures that all such activities are performed under the supervision of personnel cognizant of quality assurance and j other requirements such as radiation safety. The provision on the training and proficiency of non.

licensed personnel ensures that all such personnel will receive instruction equivalent to that given to licensed reactor operators as regards use of the medical therapy facility beam. (Note: Licensed reactor operators may, of course, operate the medical therapy facility beam.) Also, this provision provides for the posting of instructions to be followed in the event cf an abnormality.

The specification on ' recordable events' and 'misadministrations' provides for the documentation and reporting to the U.S. Nuclear Regulatory Commission of improper events regarding the generation and use of the medical therapy facility beam. The requirement that the Quality Management Program (QMP) be observed ensures that radiation treatments provided by the medical therapy facility beam will be administered as directed by the physician authorized user.

References 6.5-1 MITR Staff," Safety Analysis Report for the MIT Research Reactor (MITR-II)," Report i No. MITNE-115,22 Oct.1970, Section 10.1.3. l l

6.5-2 Choi, R.J.," Development and Characterization of an Epithermal Beam for Boron Neutron l l

Capture Therapy at the MITR-II Research Reactor," Ph.D. Thesis, Nuclear Engineering Depanment, Massachusetts Institute of Technology, April 1991, 12

4-3 -

STATE OF WASHINGTON )

)

) ss

)

COUNTY OF WHITMAN )

. On this day personally appeared before me be d #ffAte [

to me known to be the individual described in and who executed the written instrument and acknowledge that HE/$M- signed the s'ame AS HIS/ W free and voluntary act and' deed for the uses and purposes herein mentioned.

"GIVEN UNDER MY HAND AND OFFICIAL SEAL, the d -

$ day of 0bw /

, /99d .

f ,om s 7 f4.sssss 'to .& m, x f4 Nftyy Public in~ and for the State of E IY Mmel dm .

l l%.?2*i 'W

,,, s. -

Residing at #b~

i L._._, '

i 4

1 8

i 1

.