Text

Revised Proposed Tech Specs Pages Re 971003 Request for Amend to License R-37 & NRC RAI
	ML20199H266
Person / Time
Site:	MIT Nuclear Research Reactor
Issue date:	12/31/1998
From:	; NUCLEAR REACTOR LABORATORY
To:	;
Shared Package
ML20199H226	List: ML20199H220; ML20199H237; ML20199H266;
References
	NUDOCS 9901250155
	Download: ML20199H266 (55)
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6.6 Desi_en and O.peration of the Fission Convener Facility-1 Applicability This specification applies to the operation of the Fission Convener Facility. It does not pertain to the use made of the fission converter beam nor does it apply to the associated medical therapy facility. Use of that facility for the treatment of human patients and/or investigatory studies that involve humans shall be in accordance with the provisions of j TS# 6.5 and its associated quality management program. i i

The provisions of this specification are only applicable if fuel is present in the i fission converter tank.

Orcanization

~

l l

This specification contains five subsections. These are:

1 O 6.6.1 Safety Limits and Limiting Safety System Settings O

6.6.2 Limiting Conditions for Fission Convener Operation 6.6.3 Fission Converter Surveillance Requirements 6.6.4 Fission Convener Design Features 6.6.5 Reponing Requirements l

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\' 9901250155 990114

DR ADOCK 0 6-34 1.

Definiti0m

1. Fission Converter Shutdown !

That condition where the convener control shutter is fully inserted or where the l reactor is in a shutdown condition. The Dssion converter is considered to be operating l

whenever this condition is not met. I t

2. Fission Converter Secured I The overall condition where there is no fuel in the fission converter or where all of ;

the following conditions are satisGed:

.l (a) - The fission converter is shut down, !

(b) The converter control shutter (CCS) control panel key switch is in the off J position and the key is in proper custody, and l t

(c) There is no work in progress within the converter tank involving fuel, !

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t a

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6-35 i t

-_m . __ _ _ _ _ - _ _ _ _ _ . _ _ _ ... _ . _ .- _ . _ _ _ ._ _ _ . _ _ _ _.

I i

~ 6.6.1 Safety Limits and Limiting Safety System Settings l,O '

!V -

l 6.6.1.1 Safety Limits j

! Anolicability .

t This ' specification applies to the interrelated variables associated with fission i l

converter thermal and hydrauli c performance. These variables are the fission converter L

L neutronic power (P), the steady-state average primary coolant outlet temperature (Tout) if p i L under forced convection, the fission convener tank coolant mixing temperature (Tmix) if !

l. -

1 under natural circulation, the fission converter primary coolant flow rate (Wp ), and the l

fission convener primary coolant height above top of the fuel elements in the main tank j i

(H). For forced convection, the fission converter shall contain either ten or eleven fuel elements. For natural convection, the fission converter shall contain eleven fuel elements.

i Obiective To establish limits within which the integrity of the fuel clad is maintained.

Specification

1. For forced convection, the point determined by the true values of P, Wp, and Tout shall not be above the line given in Figurc 6.6.1.1-1 corresponding to the coolant height, H. l 1

2. For natural convection, the coolant height shall be at 2.4 m or higher and the point determined by the tme values of P and Tmix shall not be above the line given in Figure 6.6.1.1-2.

t e !

4 i V i

?

l 6-36

9 ...,, ...., .... . . . . . . . .

8 --

H=2.6 m 4 ,

\. * :

~

H=2.1 m .

7 + '

P (kW) . H=1.6 m Wp(gpm) . > .

6 - c -> v m

()

5 a- --

4 ' ' ' ' ' ' ' '

60 65 70 75 80 85 Tout ( C)

Figure 6.6.1.1-1 Fission Converter Safety Limits for Forced Convection.

(for either ten or eleven fuel elements)

I t

a 6-37

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

l i

40 ,,, ,,,,, ,,,, ,,,, ,,,, ,,,,, ,,,, ,,,, !

i 35 + 4 j +-~

H = 2.4 m 7 30 -

e ,

F a 25 + r 4- -+

+ . j .

c. l -

j .

20 & i 7 ,

15 + +

+ r.

10 40 45 50 55 60 65 70 75 80 l Tmix( C) l 1

j Figure 6.6.1.1-2 Fission Converter Safety Limits for Natural Convection. l (for eleven fuel elements only) ]

l 5

i !

I !

t I

l I

l i

i 4

6-38 I

t

Basis

(

V) in the MITR SAR it is noted that critical heat flux is a conservative limit beyond which fuel damage may occur from overheating. In addition, the onset of multichannel Cow instability (OFI) can lower the burnout heat flux. However, OFI is a complicated !

phenomenon and the effects of I; eat flux spatial distributions are not taken into account in the correlations developed for OFl. Onset of significant voiding (OSV), on the other hand, :

can be more accurately predicted for various heat Dux spatial distributions. OSV describes the condition where the bubbles grow larger on a heated surface and detach regularly to the main flow stream. It has been obsentd experimentally that OSV occurs before OFl.

]

Therefore, OSV is conservatively assumed as the criterion for the safety limits of the fission convener.

OSV was calculated in the Fission Convener Safety Evaluation Repon (SER) for the hot channel. Uncenainties because of depanure from nominal design specifications, ;

I

,n measurement errors, and use of empirical correlations are taken into account in these 1

V calculations. The safety limits were evaluated based on the limiting core operating conditions described in TS# 6.6.2.1. Figure 6.6.1.1-1 shows the calculated fission convener safety limits for forced convection for three coolant heights: 2.6 m, 2.1 m, and 1.6 m above the top of the fuel elements. This figure is applicable to either ten or eleven ;

i fuel elements. '

l The purpose of allowing fission convener operation at low power in the absence of I forced convection is to facilitate activities such as flux measurements in the fueled region.

Natural circulation is achieved by removing the inlet pipes, which are used for forced convection, from the downcomers. Calculations show that the natural circulation is suf6cient to dissipate the energy that is generated provided that the limit on the fission converter tank coolant mixing temperature is not exceeded. OSV for natural circulation was calculated for a coolant height of 2.4 m. This coolant height corresponds to the top of the downcomers. The result for eleven elements is shown in Figure 6.6.1.1-2.

6-39

)

6.6.1.2 Limiting Safety System Settings (LSSS)

Applicability This specification applies to the setpoints for the safety channels monitoring the fission convener neutronic power (P), the steady-state average primary coolant outlet i l

temperature (Tout)if under forced convection, the fission converter tank coolant mixing temperature (Tmix) if under natural circulation, the fission converter primary coolant flow rate (W p), and the fission convener primary coolant height above top of fuel elements in the main tank (H). For forced convection, the fission converter shall contain either ten or '

eleven fuel elements. For natural convection, the fission converter shall contain eleven fuel elements.

Ob_iective .

To assure that automatic protective actions will prevent the onset of nucleate boiling in the fission converter fueled region and will thus prevent operating conditions from I

exceeding the safety limit.

i Snecification ;

1. The measured values of the limiting safety system settings on P, Wp, Toui, and H l

- for fission convener operation with forced convection shall be as follows:

Variable Limitine Safety System Setting l P 300 kW (max) !

Wp 45 gpm (min) i Tout 60 *C (max) !

H 2.1 m above top of fuel elements (min) l.. I b]

i 6-40 i l

l 1

f

2. The fission convener may be operated at power levels up to 20 kW in the absence !

p ;

V of forced convection, provided that the inlet pipes are removed so as to allow l 1

natural circulation. The measured values of the limiting safety system settings on P, Tmix, and H for fission converter operation with natural circulation shall then be ;

as follows:

Variable Limitine Safety System Setting P 20 kW (max)

Tmix 60 C(max)

H 2.4 m above top of fuel elements (min)

Basis The limiting safety system settings (LSSS) are established to allow a sufficient margin between normal operating conditions and the safety limits, so that automatic shut v down actions will ensure that the fission converter is maintained in a safe condition during normal operation. Onset of nucleate boiling (ONB)is chosen as the criterion for the LSSS derivation. ONB (also called incipient boiling) defines the condition where bubbles first stan to form on the heated surface. Because most of the liquid is still subcooled, the bubbles do not detach but grow and collapse while attached to the wall. LSSS are chosen so that boiling will not occur anywhere in the fueled region as long as the limits are not i

exceeded.

The ONB is calculated in the Fission Convener SER for the hot channel.

Uncertainties because of depanure from nominal design specification, measurement errors,

)

and the use of empirical correlations are taken into account in these calculations. The LSSS were evaluated based on the limiting core operating conditions described in TS# 6.6.2.1.

Figure 6.6.1.2-1 shows the result of the fission converter LSSS calculations for a o primary coolant flow rate of 45 gpm and a coolant height of 2.1 m for operation with I )

v 6-41

1 forced convection. The LSSS temperature calculated for 300 kW is 63 C, and hence a f

primary coolant outlet temperature setting of 60cC is conservative.

For fission converter operation with natural circulation, calculations have shown that the prediction of ONB coincides with that of OSV because of the low flow rate.

Therefore, a 5 C margin is added to the safety limit curve to establish the LSSS. This 5 C margin corresponds to about 6 minutes of heat up time in the mixing area with the fission converter at 20 kW and thus provide adequate response time for corrective actions. The l resulting LSSS curve is shown in Figure- 6.6.1.2-2. The LSSS for fission converter operation with natural circulation is conservatively determined for a maximum power of 20 kW and a maximum coolant mixing temperature of 60 C with a coolant height of 2.4 m.

450 ,,,, ,,,, ,,,, ,,,,, ,,,, ,,,,

n 400 H = 2.1 m )

Wp = 45 gpm

()

350 S . .

6 - .

a. . .

300 250 200 '- ;

45 50 55 60 65 70 75 l l

Tout ( C) l Figure 6.6.1.2-1 Calculated Results for the Fission Converter LSSS for Operation ;

with Forced Convection. (for either ten or eleven fuel elements) 6-42

I t

I e

4 1

P i

40 ,,, ,,,, ,,,, , ,, ,,,, ,,,, ,,,, ..., i 35 4

}

H = 2.4 m -i .

. i 30 = + 4

-t F

. )

n .

g l . \

u 25 .

4- -. i

c. : i l

20 - +

t.

l

. . i

. 1

. j 15 + 4 -4 + 1

. 3 10 35 40 45 50 55 60 65 70 75 ;

i l

Tmix( C)

Figure 6.6.1.2-2 Fission Converter LSSS for Operation with Natural Convection

. (for eleven fuel elements only) 6-43

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l, 6.6.2 Limiting Conditions for Fission Converter Operation l 6.6.2.1 Limiting Operating Conditions for the Fueled Region f

Applicability This specification applies to the fission converter core operating conditions. The variables used to define the core operating conditions are:

Fp the fraction of the total power deposited in the fueled region (both fuel and coolant), ,

Fcli the ratio of the maximum power deposited in the hottest fuel plate to the average power per fuel plate, Fr the ratio of the primary coolant flow that goes through the fueled region to the total primary coolant flow, and dr the ratio of the minimum flow to the average flow in the coolant O

v channels. l Obiective To assure that the operating parameters are maintained within the bounds that are used to establish the safety limits and the limiting safety system settings of the fission 1

converter. !

Specification

1. Fpx F lic s 1.53

2. Ffx dr 2 0.80

3. After each change in loading of the fueled region which might increase the hot l channel factor, an evaluation will be made to ensure that item (1) above is satisfied.

A record of these evaluations shall be approved by two licensed SROs.

'o s

6-44

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4. All positions in the fueled region are filled with either a fuel element or another !

approved unit. TS# 6.6.2.1 (1) and (2), the safety limits, and the LSSS shall be re-evaluated for:

l l a. forced convection with other than ten or eleven fuel elements in the fueled i i

l region, and !

I

b. natural convection with other than eleven fuel elements in the fueled region. l

5. The maximum fuel burnup shall be limited in accordance with TS# 3.11(2e).

! 6. The maximum allowed value of kerr for the fueled region shall not exceed 0.90. i i

7. Fuel elements contained in the fueled region of the fission converter shall be l oriented so that the plates are " edge on" towards the MITR core.

1

8. The fission convener tank lid shall be in place and scaled for operation greater than

! 20 kW. I 1

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Basis I O

l The fission power deposition factor (Fp ), the hot channel factor (FH c), the fueled l region coolant Dow distribution factor (Fr), and the channel flow disparity factor (df) are al]

! dependent on the fission converter fueled region design. The specifications j (TS# 6.6.2.l(1) and (2)) that describe the limits on these factors are conservatively j detennined for the fission converter design and provide reasonable margin for deviations.

l These factors form the basis for the thermal-hydraulic limits calculations and they should be verified during initial startup of the fission converter.

l Safety limits and limiting safety system settings of the fission converter described in TS# 6.6.1 am derived based on eleven fuel elements in the fueled region. Calculations showed that the same SL and LSSS curves (Figures 6.6.1.1-1 and 6.6.1.2-1) can be used J for forced convection operation with ten fuel elements. However, there is a significant j effect on the SL and LSSS curves for natural convection operation with other than eleven i i

iO i 6-45

l fuel elements. Therefore, these limits shall be re-evaluated for natural convection operation O

V if other than eleven fuel elements are to be used.

The maximum fuel burnup density is chosen in accordance with TS# 3.11(2e).

This limit was developed based on the MITR fuel design.

The effective multiplication factor (kerr) for the fission convener was calculated in the SER for different combinations of coolant and fuel element U-235 content using the Monte Carlo N-Panicle (MCNP) code. The kerr values calculated for a D2 0 cooled system are 0.268 for partially spent MITR-II fuel and 0.344 for fresh MITR-II fuel. For an H2O cooled system, the kerr calculated values are 0.514 and 0.618 for panially spent and fresh MITR-II fuel, respectively. Because the kert predicted is much smaller than unity, a criticality accident is not credible. The criterion of a kertless than 0.90 was chosen because i

it is in accordance with TS# 3.10 (4) for fuel storage locations.

Calculations show that the power peaking in the hot channel would be unacceptable g if the elements were to be rotated so that fuel plates were facing the MITR. Therefore, administrative procedures will be used to ensure that fuel elements are loaded with an

" edge-on" orientation.

Operation of the fission converter without the top shield lid in place is allowed for power levels up to 20 kW. Calculations in the fission converter SER have shown that the estimated dose rate at that power level is 450 mR/h at the coolant surface with a coolant height of 2.4 m. This dose rate is not in excess of those occasionally encountered during certain maintenance operations, and it has been demonstrated that administrative actions can provide adequate controls under such conditions. Adequate controls will be instituted during such experiments to prevent excessive personnel exposure.

A 6-46

l' 6.6.2.2 Mil 3imum Allowed Reactivity Addition from the Converter Control Shutter

rN Applicability This specification applies to the reactivity worth of the converter control shutter.

Obiective l i

To ensure that the integrity of the MITR fuel is maintained during operation of the fission converter.

i Snecification l

1. The reactivity wonh of the converter control shutter shall be determined in the initial startup testing of the fission convener and verified annually thereafter.

2. The reactivity wonh of the converter control shutter shall be in accordance with TS# 6.1. ;

em Basis MITR Technical Specifications provide several approaches for limiting the reactivity associated with an experimental facility. MITR Technical Specification 6.1 imposes limits depending on whether the experiment is classified as moveable, non-secured, or secured.

Accordingly, this approach is used for the fission converter. The reactor's routine controls can be used to negate any reactivity insenion that results from opening of the convener control shutter, provided that the reactivity is less than the limit specified for a movable experiment.

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L., 6.6.2.3 Fission Converter Fuel Element Security. Storage. and Handling I

Anolicability - 1 I

This specification applies to the security, storage, and handling of the fission convener fuel elements.

Obiective To assure that the fueled elements will be properly stored and handled in a manner to protect the safety of reactor personnel.

Specification

1. All fuel elements used in the fission converter fueled region shall be maintained self-protecting. Calculations or measurements documenting self-protection shall be approved by two licensed SROs.

2. Fission converter fuel elements shall be stored in accordance with the provisions of TS# 3.10(1) and either (2) or (3) as applicable.

3. Prior to transferring an irradiated element from the fission converter tank to the transfer cask, the operating history for the element shall be in compliance with any one of the following three requirements:

(a) Continuous operation at.or below 50 kW for the four days prior to refueling. 1 (b) A maximum operating time of 4.8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months per day at or below 250 kW during i

the four days prior to refueling.

(c) A maximum bumup of 436 kWh per fuel element during the four days prior ,

to refueling.

a f

u 6-48

1 Basis TS# 3.10(4) specifies that prior to transferring an irradiated element, that fuel element shall not have been operated in the reactor core at a power level above 100 kW for atleast four days. This requirement can not be translated directly to the fission convener because of the different numbers of elements in the reactor core and in the fission convener. Altematively, an equivalent power history is used for the fission converter.

A study was conducted in the SER to calculate the fuel plate temperature during fuel element removal. It was assumed that the fission converter was operated continuously at its maximum operating power of 250 kW until four days prior to removal of the fuel element. During those four days, operation was as described in the speci0 cation. It was also assumed that all heat transfer was by radiation alone during the fuel transfer. The maximum clad temperature was calculated to be 313 C which is well below the Al-6061 softening temperature of 450 C.

I O

i 6-49

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

e 6.6.2.4 Dalli2 Concentration and Recombiner Operation -

i Aoplicability This specification applies to the D2or H gas 2 concentration in the helium cover gas !

blanket over the Hssion converter tank, and to the operation of the recombiner system. In the event that the fission converter is operated without its top shield lid, this specification is not applicable.

i Objective To prevent a flammable concentration of either D 2 or H2gas in the helium blanket. .

l l

Sneci6 cation

1. The D2concentration in the helium blanket shall not exceed 6 volume percent if D 20 is used as the primary coolant in the fission converter.

O 2. The H2concentration in the helium blanket shall not exceed 6 volume percent if H 2O is used as the primary coolant in the Gssion convener.

3. The recombiner shall be operated for a minimum of 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months per month in any month during which the Ession converter was operated.

4. In the event that the recombiner is not operable, fission converter operation may be continued provided that D2 /H2 samples are taken weekly, and that the D2/H2 l concentration in the helium blanket does not exceed 2 volume percent. !

l Basis Recombination of the disassociated D 2 /H2 and O 2 is accomplished by circulating the helium from above the fission convener tank through a recombiner.

O 6-50

The concentration limit of D 2 /ll2in helium blanket is obtained from TS# 3.3(1), in which the concentration is conservatively determined from extrapolation of flammability limits.

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6-51

l 6.6.2.5 Fission Convener Safety System O Aoplicability This specification applies to the operability of the fission convener safety channels.

Obiective To assure that adequate automatic protective actions are provided by the safety channels during operation of the fission converter.

i Snecification

1. The Ession converter shall not be operated unless the safety channels listed in Table 6.6.2.5-1 are operable.

2. Emergency power with the capacity to operate the equipment listed in Table 6.6.2.5-2 of this specification shall be available whenever the fission converter is operating and shall be capable of operation for at least one hour following a loss of normal power to the facility.

3. There shall be an alarm at 110% orless of the fission convener's nominal operating power for fission converter operation using forced convection. The fission converter's nominal operating pmver shall be determined in accordance with TS#

6.6.4.8. This alarrn shall not exceed 275 kW.

4.. There shall be a reactor scram at the reactor power corresponding to the fission converter power 20 kW or less for fission converter operation using natural convection.

F 6-52

l

, Basis

! The parameters listed in Table 6.6.2.5-1 are monitored by the fission converter safety system. This system automatically initiates converter control shutter closure and/or a j reactor scram to assure that the LSSS and safety limits are not exceeded.

The use of emergency power is not essential for the fission convener because loss l of power automatically scrams the reactor and thus the fission converter. Both the mechanical and water shutters close by gravity upon power failure. Nevertheless, the information supplied to the reactor operator and fission converter user that the fission l

convener is shut down will assure personnel radiation safety. The choice of a minimum of one hour is based on TS# 3.7(3).

i For forced convection cooling, protection against a fission converter overpower l condition is provided by an alarm at i10% of nominal operating power and an automatic CCS closure at the over-power setpoint 275 kW. A reactor scram on fission converter 1

G overpower is not needed because the reactor itself will have aheady scrammed on high I (b power. For natural convection cooling, protection against a fission converter overpower condition is provided by a reactor scram at the reactor power corresponding to the fission converter power 20 kW or less for fission converter operation using natural convection.

e This different approach is necessary because an overpower condition can occur on the fission converter during natural convection cooling even though the reactor itself is operating within its licensed operating power.

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6-53

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l Table 6.6.2.5-1 Minimum Required Safety Channels for Fission Converter Operation !

Channel Automatic Action Setpoint Min. No. 1 Range Required Operation with Forced Convection Flow Primary Flow Rate Reactor Scram

and 2 45 gpm 1 Converter Control Shutter Closure Power Reactor Scram ** and 5 300 kW l Converter Control Shutter Closure Outlet Temperature Converter Control Shutter Closure s 60 C 1 Coolant Level Reactor Scram

and 2 2.1 m 1 Converter Control Shutter Closure Manual Reactor Minor Scram Reactor Scram

N/A 1 from the Fission Converter

/O Medical Control Panel

%)

Operation without Forced Convection Flow Power Converter Control Shutter Closure s 20 kW l Outlet Temperature Converter Control Shutter Closure s60 C 1 Coolant Level Reactor Scram

and 2 2.4 m 1 Converter Control Shutter Closure Manual Reactor Minor Scram Reactor Scram

N/A 1 from the Fission Converter Medical Control Panel Not required if fission converter is in either a shutdown or a secured condition.

For natural convection operation only and not required if fission converter is in either a shutdown or a secured condition.

O 6-54

f rn i I

G Table 6.6.2.5-2 Minimum Equipment to be Supplied by Emergency Power

1. Fission converter medical therapy room radiation monitor.

2. Intercom between the fission convener medical therapy room and its associated medical control panel area.

3. Intercom between the fission converter medical control panel area and the reactor control room.

4. Emergency lighting of the fission convener medical therapy room and its associated medical control panel area.

5. Outlet temperature and coolant level channels listed in

( Table 6.6.2.5-1.

f*)

U 6-55

6.6.2.6 Fission Converter Primary Coolant Ouality Reauirements

\

Applicability This specification applies to the pH, conductivity, and activity of the fission convener primary coolant.

Obiective I

g To control corrosion-of the fission converter fuel and primary coolant loop

,y structure, and activation of impurities and leakage of fission products in the fission converter primary coolrrct. !

l Snecification

1. The pH of the fission converter primary coolant shall be kept between 5.5 and 7.5, except as noted .in provision (4) below.

2. The conductivity of the fission converter primary coolant shall be kept less than 5 pmho/cm at 20 C, except as noted in provision (4) below.

3. Any gross -y sample activity that exceeds the average of the previous monthly values (normalized by power) by a factor of three or more shall be investigated to determine the cause.

L 4. Operation of the fission convener with the pH or conductivity outside the limits 1

given in (1) and (2) above is permitted provided:

a. the pH is between 5.0 and 8.0,

[ b. any increase in conductivity is not the result of a chloride ion concentration in excess of 5 ppm,

c. sampling of the fission converter coolant is done at least once every eight l hours, and !

l

! d. the pH band specified in provision (1) is re-established within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months .

, Otherwise, the fission convener shall not be operated.

6-56 i

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Basis :

V The purpose of pH monitoring is to ensure corrosion on the fission conver1er fuel {

and the primary coolant loop structure is maintained within an acceptable limit. The fission l

converter fuel cladding and the fission converter tank are made of aluminum alloy. A l l

portion of the primary coolant loop is constructed of stainless steel. Lower pH will reduce

{

aluminum alloy corrosion and oxide film formation on the fuel surface and higher pH is favored to control stainless steel corrosion. Thus a pH range between 5.5 and 7.5 is l

selected for the fission converter primary coolant. i l

Electrical conductivity is also monitored to control purity of the fission converter l

primary coolant. A conductivity limit of 5 pmho/cm has been traditionally adopted by research reactors.

The criterion that gross -y activity three times in excess of the average value be investigated is in accordance with industry practice for the detection of incipient fuel failure.

~

In order for this criterion to be applied with a consistent basis, only samples that have similar power histories should be compared. l l

Operation with out-of-specification chemistry is acceptable for short intervals. The important factors are pH and the absence of a high chloride concentration. A high conductivity by itselfis not of concern.

l l

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O 6-57 1

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l. 6.6.3 Fission Converter Surveillance Reauirements l l ~ rQ v

Applicability This specification applies to the surveillance of safety systems whose operation is important to fission converter safety. !

l Obiective ;

To assure the reliability of the instrumentation important for safe operation of the ;

i L

fission converter. ;

1 i

Specification .

1. The following instruments or channels for the fission convener safety system will be tested at least monthly and each time before startup of the reactor if the reactor has been shut down more than 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months and if the fission converter facility will be l C

\

used within that reactor operating period. The monthly requirement may be omitted if the fission converter facility will not be used during that month.

Instrument. Channel. or Interlock Functional Test Primary coolant flow Automatic converter control shutter closure and reactor scram Power level Automatic converter control shutter closure i Primary coolant outlet temperature Automatic converter control shutter closure Fission converter tank coolant level Automatic converter control shutter closure j and reactor scram

2. The following instmments used in the fission converter facility shall be calibrated L

and trip points verified when initially installed, any time the instrument has been repaired, and at least annually:

6-58

l l

l a. Neutron flux level channel,

b. Primary coolant flow channel,

c. Primary coolant outlet temperature channel, and

d. Fission converter tank coolant level channel.

3. The neutron flux level channel and a fission converter primary system heat balance 1

shall be checked against each other at least annually and when design changes in the reactor and/or the fission converter are made that may affect the r xisting calibration result.

4. The pH and gross -y activity of the fission converter primary coolant shall be determined at least monthly. The conductivity of the fission convener primary coolant shall be determined either by a continuous on-line instrument or a monthly sample. The tritium content of the coolant shall be determined quarterly if D2 O is used as the fission convener primary coolant.

CT U Basis The specifications for functional tests, calibrations, and primary coolant sampling adhere to current MITR practice.

The annual frequency for performance of the calorimetric was chosen because the fission converter's power is a function of the MITR's power and the burnup of the fission converter fuel. The latter will occur very slowly. Hence, the annual performance of a calorimetric is sufficient to detect any change in fission converter power production.

Experience with the MITR primary and D20 systems has shown that an out-of-specification chemistry condition is extremely rare. Heat fluxes present in the fission convener are too low to contribute to fuel cladding degradation in the event of out-of-

! specification chemistry. Continued operation of the fission converter is thus permitted.

I v

6-59

i 6.6.4 Fission Converter Desien Features

<-~s -

Anolicability This specification applies to the design of the fission converter tank, fueled region, and primary coolant system.

Objective To assure compatibility of the fission converter design features with the present safety evaluation.

Specification i

1. The fission converter primary coolant system can utilize either H2 O or D2O coolant.

2. All materials that are in contact with primary coolant, including those of the converter tank, shall be aluminum alloys, stainless steel, or other materials that are (nj chemically compatible with H2O and D2 O coolant, except for small non-corrosive l components such as gaskets, filters, and valve diaphragms. i

3. The fueled region of the fission converter may consist of up to eleven fuel elements of a type described in TS# 5.2(1).

4. The fueled region of the fission converter may contain sample assemblies provided that they confonn to the requirements of TS# 6.6.2.l(4). Design of the sample assemblies shall also conform to the following criteria:

a. they shall be secured either by a mechanical device or by gravity to prevent movement during fission converter operation, l

b. materials of construction shall be radiation resistant and compatible with those used in the fission converter fueled region and primary coolant system,

(^\

V 6-60

c. sufficient cooling shall be provided to insure structural integrity of the

,f3 V assembly and to preclude any boiling of the primary coolant, and

d. the size of the irradiation thimble shall be less than 16 square inches in cross section.

5. The removable aluminum block shall be installed in the fission converter tank unless calculations to show compliance with TS# 6.6.2.1 (1), (2), and (6) have been performed for another configuration. Other configurations could include but are not limited to a block of a different material, the absence of the block, or a i

combination of a solid material and coolant. ;

6. The pumps and other components of the fission converter's primary cooling system shall be located so as to prevent uncovering of the fission converter fuel elements as a result of siphoning.

7. The following interlocks shall be installed in order to prevent fission converter operations under abnormal conditions:

p]

N' a. Interlock that prevents opening of the convener control shutter without the i

fission convener primary flow scram operable (forced convection operation only).

b. Interlock that prevents opening of the converter control shutter without the l

fission converter coolant level scram operable.

c. Interlock that automatically closes the water and mechanical shutters when the medical room control panel key switch is turned to the OFF position.

d. Interlock that ensures the CCS will close automatically when the CCS control panel key switch is in the OFF position.

e. Interlock that prevents startup of the MIT Research Reactor unless the CCS l is in the fully closed position.

8. The fission converter's nominal operating power for the given combination of

(]

v MITR licensed power, fission convener coolant (H2 O or D2 0), and U-235 content l 6-61 l

l

l-l of the fission converter fuel shall be estimated prior to initial use and confirmed

[ during initial use.

l l Basis l The two materials specifications are in keeping with those imposed on the design of ,

I l the MITR. The specifications on fuel type and sample assemblies impose the same criteria l l as used for the MITR. '

l Design criteria for the sample assemblies were adopted from the existing i 1

specification for the MITR in-core sample assemblies TS# 5.2.2.

]

Removing or replacing the movable aluminum block with other material may cause ;

l a different power distribution as well as changing kerr. Therefore, any change in ,

1 configuration shall be evaluated to show compliance with existing technical specifications.

l l

l 1

)

tO

, 6-62 1

I l

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

6.6.5 Reportine Reauirements G

Applicability This specification applies to the reporting requirements and the contents of the initial startup tests of the fission converter system. ;

Obiective To assure that adequate management controls are available for safe operation of the ;

fission converter.

SIrcification

1. A written report to the Document Control Desk, USNRC, Washington, D.C shall be made within 90 days after completion of the stanup testing of the fission convener that is required upon receipt of a new facility license or an amendment to

/\

O the license authorizing an increase in fission converter power level. This repon l shall describe the measured values of the operating conditions or characteristics of the reactor under the new conditions, including:

a. An evaluation of facility performance to date in comparison with design ;

l predictions and specifications; and

b. A reassessment of the safety evaluation submitted with the license application in light of measured operating characteristics when such measurements indicate that there may be substantial variance from prior )

evaluation.

2. The startup report shall include the following items:

a. measurements and comparison to prediction of subcritical multiplication for the initial fuelloading,

b. measurements and comparison to prediction of flow disparity, b,n 6-63 l

L . _ __

c. measurements and comparisons to prediction of nuclear hot channel factor, O and

d. fission converter power measurements and calibrations.

O

~

6-64

4

O j

1 i

1 CHANGES TO l CURRENT MITR

TECHNICAL SPECIFICATIONS i

lO l DECEMBER 31,1998 O

p 1. DEFINITIONS d

1.1 Reactor Secured l

The overall condition where there is no fuel in the reactor core or all of the following conditions are satified:

1. the reactor is shut down,

2. console key switch is off and key is in proper custody,

3. no work in progress within the main core tank and/or the fission converter tank involving fuel or experiments, or maintenance of the core structure, l installed control blades, or installed control blade drives when not visibly decoupled from the control blade.

1.2 Reactor Shutdown That condition where all control blades are fully inserted or reactivity condition Q equivalent to one where all control blades are fully inserted. The reactor is considered to be l (LJ operated whenever this condition is not met.

1.3 Containment Integrity Integrity of the containment building is said to be maintained when all isolation system equipment is opersble or secured in an isolating position.

1.4 The True Value l

The tme value of a parameter is its exact value at any instant.

1.5 The Measured Value The measured value of a parameter is the value of the parameter as it appears on the output of a measuring channel.

p.,

^G l 1-1

a. a radiation monitor continually sampling the effluent air stream, which indicates in the control room, shall be operating and capable of automatically closing the building vents. The time for the radiation monitor trip, including sample transit and ventilation damper c.c.,ing times, shall be less than the time for efDuent air to flow from the sampling point to the damper.

b. a radiation monitor in the exhaust stack shall be operating,

c. the tritium concentration in the stack effluent shall be measured so as to provide a monthly average value. !

3. Whenever the reactor is operating with secondary cooling water circulating between the reactor building and the cooling towers, a secondary water radiation monitor, which indicates in the control room, shall be operating.

4. Whenever secondary cooling water is flowing through the D20 heat exchangers and/or the fission converter heat exchanger (if D2O is used as coolant) to the cooling towers the following shall be provided:

a. the secondary water shall be sampled daily for tritium content.

b, the level of the D2O dump tank shall be monitored, either by a low level alarm in the control room, or by hourly readings of the dump tank sight glass.

c. the level of the f'ssion converter tank shall be monitored by a low level alarm in the control room or by hourly reading of a local guage.

5. At least one area radiation monitor, capable of warning personnel on the reactor floor of high radiation levels, shall be operating when the reactor floor is occupied.

If one of the five normal area monitors is inoperative, portable instruments will be used to survey work in that area.

O 3-27

's amw m

1 l

O

() a. in the reactor core provided the reactivity is below the shutdown i

margin given by Specification 3.9-1,

b. in the cadmium-lined fuel storage ring attached to the flow shroud,

c. in the dry storage f 'es on the reactor top,

d. in the spent fuel storage tank in the basement of the reactor building,

e. in the fuel element transfer flask or other proper shield within the controlled area,

f. in the fission converter tank. l

4. Handling of fuel elements: Only one fuel element at a time shall be moved ;

i in or out of the reactor core. Not more than four of the MITR fuel elements or the equivalent of two fuel elements including loose plates (maximum of 15 loose fuel plates) shall be outside of the storage areas as designated in items 2 and 3a, b, c, d except during the processes of receiving or shipping i k fuel from the site in approved containers. In all cases of fuel element storage outside of the reactor core, the value of kerr must be kept less than 0.90. Records of fuel element transfers shall be maintained. Prior to transferring an irradiated element from the reactor vessel to the transfer i.

l flask, the element shall not have been operated in the core at a power level above 100 kW for at least four days.

5. Removal of control blades: A control blade may be removed from the core only if the minimum shutdown margin relative to the cold, Xe-free critical l

l condition with the most reactive operable blade and the regulating rod fully i

withdrawn is 1% Ak/k after the control blade has been removed.

l l

1

.(s) 3-37 !

O lt has been calculated that fuel elements when stored in the locations specified in 2b, 2c,2d,3b,3c,3d, and 3f will have a calculated effective multiplication (kerr) factor ofless

. than 0.9 under optimum conditions of water moderation.

These specifications are also conservative for criticality safe handling of MITR-1 fuel alone or in combination with MITR-Il fuel.

The chief additional problems with spent fuel are those of shielding personnel from the emitted fission product gamma rays and preventing melting from afterheat. The shielding requirement is met by utilizing a shielded transfer flask for movements and temporary storage and more permanent shielding as indicated in 3a, b, c, d, and f. The requirement to prevent melting is met by specifying that four days elapse between use of the fuel element in a core operating above 100 kW and removal of the element from the

(

r reactor pool. This decay time was determined from experience with the MITR 1 combined with a conservative assumption of doubling the power density for the MITR-II.

The specification on removal of control element provides that the stuck rod criteria will always be met, even when one blade is removed for repair. Thus, the reactor still L would not go critical on the removal of a second control element.

l:

l l

L j

!' i LO:

I 3-39 4

, - n , y,s , , , , , - - - -

6.5 Generation of Medical Theraov Facility Beams for Human Theraov Anolicability This specification applies solely to the generation of medical therapy facility beams for the treatment of human patients. It does not apply to any other use of the medical therapy facilities and/or their beams. Surveillances listed in this specification are required only if j 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 protection of the public health and safety by ensuring that patients are treated in accordance with the treatment plan established by the BNCT physician authorized user and that the ALARA principle is observed for all non-therapeutic radiation exposures.

l Specification

1. Patients accepted for treatment shall have been referred by written directive from a l BNCT physician authorized user from a medical center with an NRC or Agreement

! State medical use license that contains BNCT specific conditions and commitments !

9 for BNCT treatment on humans conducted at the Massachusetts Institute of l Technology Research Reactor's Medical Therapy Facilities.

2. All medical treatments, including irradiations and analyses of the neutron capture agents in the patients, are the responsibility of the BNCF phyacian authorized user in charge of the therapy and the medical physicists from the NRC-licensed or Agreement State-licensed medical center. The Massachusetts Institute of Technology

is responsible only for providing current and accurate beam characteristic parameters l

l to the medical use licensee and for delivery of the desired radiation fluence as

, requested in the written directive. Before the start of a therapy, both the certified medical physicist and the Director of the Nuclear Reactor Laboratory, or his designate, must agree that the therapy can be initiated. The BNCT physician 4

6-21 i

j l

g authorized user is responsible for monitoring the therapy and for directing its i /

\/ tennination. However, a radiation therapy can also be terminated at any time if either the BNCT physician authorized user or the NRL Director, or their designates, judge that the therapy should be tenninated.

3. It shall be possible to initiate a minor scram of the reactor from a control panel located in each medical therapy facility area. In the event that a medical facility rninor scram is inoperable, it shall be acceptable to use one of the control room scrams via communication with the reactor opewr as a temporary means of satisfying this provision. Use of this temporary provision is limited to seven consecutive working days.

4. Access to each medical therapy facility shall be controlled by means of the shield door located at its entrance.

5. The following features and/or interlocks shall be operable:

(]

uj (a) An interlock shall prevent opening of the shutters that control beam delivery unless the medical therapy facility's shield door is closed.

(b) The shutters that control beam delivery shall be interlocked to close automatically upon opening of the medical therapy facility's shield door.

(c) The shutters that control beam delivery shall be designed to close automatically upon failure of either electric power or on low air pressure if the shuner is operated pneumatically.

(d) Shutters that control beam delivery and that are normally pneumatically-operatec'shall,in addition, be designed for manual closure.

(c) It shad be possible to close the shutters that control beam delivery from within the medical therapy facility.

6. Each of the shutters that controls beam delivery shall be equipped with a light that indicates 1,he status of the shutter. These lights shall be visible at each medical U therapy facility's local control panel. In the event of a status light malfunction, it shall be acceptable to use the affected shutter provided that an alternate means of 6-22

r l I i

verifying position is available. Use of this alternate means of shutter position verification is limited to seven consecutive working days.

l

7. Each medical therapy facility shall be equipped with a monitor that provides a visual l t .

indication of the radiation level within the facility, that indicates both within the i facility and at the local control panel, and that provides an audible alarm both within the facility and at the local control panel.

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

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

I I (c) This radiation momtor shall be calibrated quarterly. ;

l (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's shield door. i 1

(e) In the event that this monitor is inoperable, personnel entering the medical !

therapy 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 MIT Research 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-l provision is limited to seven consecutive working days.

8. An intercom or other means of two way communication shall be operable both

! between each medical therapy facility control panel and the reactor control room, and also between each medical therapy facility control panel and the interior of the l

}

i facility. The latter is for the monitoring of patients.

i I 6-23

9. It shall be possible for personnel monitoring a patient to open each medical therapy facility's shield door manually.

10. It shall be possible to observe the patient tinough both a viewing port and by means of a closed-circuit TV camera. Both methods of patient visualization shall be operable at the outset of any patient inadiation, Should either fail during the irradiation, the treatment may be continued at the discretion of the BNCT physician authorized user. Adequate lighting to permit such viewing shall be assured by the provision of emergency lighting.

I1. 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 treatment is normally delivered in fractions in accordance with standard practice for human therapy. The 20% criterion applies to the sum of the radiation fluences associated with all fractions in a given treatment plan. A criterion of 30% applies to the difference between the administered and prescribed 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.

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

)~

l Interlock or Channel Surveillance ;

i-l a) Medical therapy facility minor scram Scram test b) Shutters will not open unless Operational test l shield door is closed j c) Shutters close upon both manual and Operational test

. automa:ic opening of shield door j d) Shuners close on loss of electrical Operational test

power and reduction of pressure i m pneumatic operators,if applicable c) Manual closure of pneumatic shutters Operational test l

1 ;

i l 6-24

f) Shutters can be closed manually Operational test l from within the facility '

g) Shutter status lights Operational test h) Radiation monitor alarm Operational test

~

l i) Radiation monitor and/or alarm Operational test '

enabled upon opening of shield door j) Intercoms Operational test In addition to the above, each medical therapy facility minor scram shall be tested prior to reactor stanup if the reactor has been shut down for more than sixteen hours.

13. Manual operation of each medical therapy facility's shield door in which the door is opened fully shall be verified semi-annually.

14. Use of the medical therapy facility beams 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 1 ~. of this specification shall be made weekly for any week that the beam will be used for human therapy. These checks shall be t

~O made prior to any patient irradiation for a given week. In addition, a calibration check shall be performed prior to any patient irradiation in the event that any corr.ponent of a given beam design has been replaced. Finally, a calibration and a functional check shall be performed prior to any patient irradiation in the event of a component replacement.

1 b) A characterization of the beam shall be performed every twelve months for any l twelve-month interval that the beam will be used for human therapy. This twelve-month characterization shall be made prior to any patient irradiation for a given twelve-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 6-25

l l

interval that the beam will be used for human therapy. The two-year calibration lC) shall be made prior to any patient irradiation during any given two-year interval.

15. Maintenance, repair, and modi 0 cation of the medical therapy facilities shall be l performed under the supervision of a senior reactor operator who is licensed by the U.S. Nuclear Regulatory Commission to operate the MIT Research Reactor. The

' medical therapy facility' includes the beam, beam shutters, beam monitoring I equipment, medical therapy facility shielding, shield door, and patient viewing 1

equipment. All modi 0 cations will be reviewed pursuant to the requirements of 10 l l

CFR 50.59. The operating couch, patient positioning equipment, medical instruments, and other equipment used for the direct medical suppon of the patient are not considered pan of the medical therapy facility for purposes of this provision, except insofar as radiation safety (i.e., activation and/or contamination)is concerned.

p 16. Personnel who are not licensed to operate the MIT Research Reactor but who are U responsible for either medical therapy or beam design including construction and/or modi 0 cation may operate the controls for the corresponding medical therapy facility beam provided that:

(a) Training has been provided and pronciency satisfactorily demonstrated on the design of the facility,its controls, and the use of those controls. ProDciency 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 roorn before tuming the l 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

- <(o condition occurs. A directive shall be included with these instructions to notify the reactor console operator in the event of any abnormality.

6-26

I

(c) In the event that a shutter affects reactivity (e.g., the D 2 O shuttr for the l

!fq medical room below the reactor and the converter control shutter for the

!O fission converter beam), personnel who are not licensed on the MIT Research Reactor but who have been trained under this provision may operate that i shutter provided that verbal permission is requested and received from the ,

l reactor console operator immediately prior to such action. Emergency closures are an exception and may be made without first requesting permission.

Records of the training provided under subparagraph (a) above shall be retained in i accordance with the MIT Research Reactor's training program or at least for three l

years. A list of personnel so qualified shall be maintained in the reactor control i room, l

17. Events defined as ' recordable' under definition 8 of this specification shall be recorded and the record maintained for five years. Events defined as (3

%.)

'misadministrations' under definition 9 of this specification shall be reported to the U.S. Nuclear Regulatory Commission (24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months verbal,15 day written report). The 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months verbal reports will be made to the Regional Administrator, Region 1, or his designate. The 15 day written reports will be sent to the NRC Document Control Desk with a copy to the Regional Administrator, Region I, or his designate.

18. The requirements of the Quality Management Program (QMP) for the Generation of Medical Therapy Facility Beams for Human Therapy at the Massachusetts Institute of Technology Research Reactor shall be observed for any human therapy. (Egig: The I presence of this 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 MITR Technical Specifications.)

o 6-27

I i

Definitions

1. The medical therapy facilities are equipped with shutters that are used (i) to control l

beam delivery and (ii) to adjust the neutron energy spectrum of the beam. The former currently iralude lead, boral, and light water shutters as described in l

l Reference 6.5-1. The heavy water blister tank, which is also described in Reference 6.51,is an example of the latter. It is conceivable that these designations may change should it be found desirable to alter the beam configuration. Accordingly, the phrase " shutters that control beam delivery" refers either to the aforementioned three I existing shutters or to any future shutter or group thereof that provides an equivalent

or greater reduction in beam intensity. Shutter-effect analyses shall be documented through the standard safety review process including, where appropriate, an SAR i

! 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 one or more of the following: foil activatioin use of a fission chamber; l

use of an ion chamber; or an equivalent process. The purpose of a calibration check is to ensure that the beam has not changed in a significant way (e.g., energy spectrum or intensity) from the beam that was characterized.

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

system output is consistent (i 10%) 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 as described in Reference 6.5-2 or an equivalent process. The dose-versus depth profile from the surface of the phantom to a depth at least equivalent to the total thickness of the body part to be treated on a central axis is deemed adequate for a characterization. Fast neutron, thermal neutron, and gamma

} cy components are determined in a characterization and monitors are normalized by iO 4

6-28

l

5. The term ' calibration of the beam monitors' refers to the process whereby the beam m

h monitors that are described in provision 11 of this specification are calibrated against instruments that measure dose including a tissue-equivalent chamber and a graphite i

or magnesium wall ionization chamber (or the equivalent to any of these three) that have in tum been calibrated by a secondary calibration laboratory.

6. The term ' design modification' as applied to a medical therapy facility beam refers (a) to a change that is shown to alter the dose versus-depth profile of the fast neutrons, thermal neutrons, or gamma rays in the beam as sensed by the calibration check and (b) to a change that has the potential to increase 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 emitted in a medical therapy facility beam. The determination of the ratios of

,, gamma, fast neutron, and thermal neutron fluences is part of the beam

/\

l \b characterization. Knowledge of these ratios allows the total radiation fluence to be i monitored by the on line detectors, which are neutron-sensitive. Compliance with l

the limits specified on radiation fluence by this specification is determined by reference to the fluence monitored by these detectors.

8. The term 'rei ' rdable event

means the administration of:

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

(b) A radiation treatment where a written directive is required without reporting to l the medical use licensee in writing each fluence given within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of the treatment; 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 treatment

'v site; or 6-29

(b) When the treatment delivery is not in accordance with provision 11 of this specification.

d,A

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

{

fmetion, and overall treatment period.

l

11. The term 'l uman therapy' means radiation treatments that are of direct therapeutic l

benefit to the patient and/or part of investigatory studies that involve humans.

j

12. The term 'BNCT physician authorized user' means a medical physician authorized by the medical use licensee's radiation safety committee to act as an authorized user for i BNCT on humans.

13. The term 'rertified 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.

14. The term ' design modification' means installation of an approved component for l which characterization has not previously been performed.

15. The term ' component replacement' means the replacement of an identical unit or re-l installation of a component for which a characterization has already been performed.

For example, the latter may be a change of collimators.

l Basis The stipulation that patients be accepted only from a medical use licensee that has an NRC or l an Agreement State medical use license that contains BNCT spet.if c conditions and i

l commitments for BNCT treatment of humans conducted at the Massachusetts Institute of !

Technology Research Reactor's Medical Therapy Facilities ensures that medical criteria imposed by NRC or the Agreement State on such licensees for the use of the MIT Research O

b Reactor's medical therapy facility beams for human therapy will be fulDiled. The second 6-30 l

i 7 provision delineates the division of responsibilities between the Massachusetts Institute of (v) Technology imd 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 ndnor scram from control panels located in the medical therapy facility areas assures the attending physician and/or medical physicist of the capability to terminate the treatment immediately should the need arise. The provision that access to each medicol therapy facility be limited to a single door ensures that there will be no inadvertent entries. The various interlocks for the shutters that control beam delivery ensure that exposure levels in the medical therapy facility will be minimal prior to entry by personnel who are attending the patient. The shutter-indication lights serve to notify personnel of the beam's status. The provision for a radiation monitor ensures that personnel will have information available on radiation levels in the medical therapy facility prior to entry. The purpose of this monitor's audible alarm is to alert personnel to the pres.ence of elevated (3 radiation levels, such as exist when the shutters that control beam delivery are open. This

\")

monitor and/or its alarm may be disabled once the medical therapy facility has been warched and secured so that it will (1) not disturb a patient at)d (2) not distract attending personnel. l l

The monitor and/or its alarm 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 perso.mel and the reactor operator (s). The second intercom is for monitoring the patient.

The provision for manual operation of each medical therapy facility's shield door ensures access to any patient in the event of a loss of electrical power. The presence of a viewing window and a closed-circuit TV camera provide the attending BNCT 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

()

r v

electric power failure because of the provision for emergency lighting.

6-31

The speci0 cation that the total radiation Duence for a therapy (i.e., the radiation fluences for

]v the sum of all fractions speciDed in a given treatment plan) not exceed that prescribed in the patient treatment plan by 20% establishes a trigger limit On the delivered Duence above which NRC has to be noti 6ed 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 difference between the administered and prescribed Duence 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 CPR 35.2. Finally,if a treatment involves three or fewer fractions, then a more stringent cri'.erion,10%, applies to the difference between the total radiation Duence for a therapy and that prescribed in the treatment plan (10 CFR 35.2(4ii)). The surveillance requirements for beam calibration checks and characterizations provide a mechanism for ensuring that each 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 NationalInstitute of Stondards and Technology.

) The chambers specified (tissue-equivalent, and graphite or magnesium-wall) were chosen because they measure dose as opposed to fluence.

The specification on maintenance and repair of the medical therapy facilities ensures that all l such activities are performed under the supervision of personnel cognizant of quality assurance and other requirements such as radiation safety. The provision on the training and pro 6ciency 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 beams. (Note: Licensed reactor operators may, of course, operate the medical therapy facilky beams.) Also, this provision provides for the posting of instructions to be followed in the event of 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 medical therapy facility beams. The requirement

!n\/

e V that the Quality Management Program (QMP) be observed ensures that radiation treatments 6-32

provided by a medical tF,oapy facility bearn will be administered as directed by the BNCT physician autholized user. -

ReferenscJ.

6.5- 1 MITR Staff, " Safety Ancdysis Report for the MIT Research Reactor (MITR-ll),"

R. pon No. MITNE-115,22 Oct.1970, Section 10.1.3.

6.5-2 Choi, R.J., " Development and Characterization of an Epithermal Beam for Boron Neutron Capture Therapy at the MITR Il Research Reac!or," Ph.D. Thesis, Nuclear Engineering Department, Massachusetts Institute of Technology, April 1991.

1 O l O

6-33

e i

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Ouality Management Program i

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1 Ouality Manacement Procram: Generation of MITR Il Medical Therany Facility Beam O' for Human Theraov 1

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Purpose:

The objective of this quality management program is to ensure that radiation treatments provided by the MIT Research Reactor's (MITR-II) Medical Therapy Facility beams will be administered as directed by a BNCT physician [

authorized user.

2. Authorized Medical Use Licerisees: Use of the MIT Research Reactor's Medical Therapy Facility beams, for the treatment of human subjects, is limited to the )

BNCT physician authodud users from medical centers with an NRC or Agreement 1 l

State medical use license that contains BNCT specific conditions and commitments for BNCT treatment on humans conducted at the Massachusetts Institute of Technology Research Reactor's Medical 'lherapy Facilities. l

3. Program Requirements: The fo!Iowing requirements are established as part of this quality management program:

! (a) A written directive will, except as noted in subparagraph (iv) below, be l prepared by a BNCT physician authorized user of either the NRC or j Agreement State medical use licensee prior to the administration of any i

radiation therapy. This directive shall be written, signed, and dated by the i BNCT physician authorized user and it shall include the following information:

(i) Name and other means ofidentifying the patient.

(ii) Name of the BNCT physician authorized user and certified medical physicist in charge of the therapy.

(iii) The total radiation fluence to be administered, the radiation fluence per fraction, the treatment site, and the overall treatment period.

. (iv) If, because of the patient's condition, a delay in order to provide a wrinen revision to ar: existing written directive would jeopardize the

! patient's health, an oral revision to an existing written directive will x acceptable, provided the oral revision is documented immediately in the patient's record and a revised written directive is signed by a BNCT physician authorized user within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months of the oral revision.

Also, a written revision to an existing written directive may be made for any therapeutic procedure provided that the revision is dated and signed by a BNCT physician authorized user prior to the administration of the next fraction.

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! If, because of the emergency nature of the patient's condition, a j delay in order to provide a written directive would jeopardize the patient's health, an oral directive will be acceptable, provided that

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the information contained in the oral directive is documented immediately in the patient's record and a written directive is prepared

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within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of the oral directive.

i (v) In order to ensure that the Staff of the MIT Research Reactor has the l

most recent written directive from the medical use licensee and the conect directive for the patient in question, a copy of that directive

2-shall be hand-delivered to the MITR Staff by the Staff of the medical (q

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use licensee who accompany the patient to MIT. This copy shall then be checked against the most recent previous transmission. Any discrepancy shall be resolved by the medical use licensee prior to the ;

initiation of patient irradiation.

(vi) The Director of the MIT Nuclear Reactor Laboratory, or his designate, will date and sign the written directive to verify that current and accurate beam characteristic parameters were provided to the NRC or Agreement State medical use licensee as appropriate and that the radiation fluence dedred in the written directive was delivered. A copy of this signed directive shall be provided to the medical use licensee within twenty-four hours of a treatment.

(b) Prior to each administration of any radiation, the patient's identity will be verified by more than one method as the individual named in the written directive. The MIT Nuclear Reactor Laboratory will use any two or more of the following acceptable methods ofidentincation:

(i) Self-identiDeation by patients who are conscious upon arrival at the MIT Research Reactor. Information provided by the patient shall include any two of the following: name, address, date of birth, or social security number. The information provided by the patient is to be compared to the corresponding information in the patient's j record. i Hospital wrist band identincation with the wrist band information to l Q (ii) be compared to the corresponding information in the patient's (j record.

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(iii) Visual identiGcation against photographs provided with the written directive.

(iv) Other methods as speciDed in U.S. Nuclear Regulatory Commission Regulatory Guide 833, " Quality Management Program."

(c) The plan of treatment is cenined by the certified medical physicist to be in accordance with the written directive. In this regard, the Massachusetts Institute of Technology is responsible for calibrating the output of the beam ;

monitoring instrumentation versus dose in phantom and for providing a l central axis dose versus depth profile. This information will then be used by personnel at either the NRC or the Agreement State medical use licensee as appropriate to generate a plan of treatment. Conformance of the beam to its design characteristics is conDrmed through the measurements specined in MITR Technical Specification #6.5, " Generation of Medical Therapy Facility Beams for Human Therapy." Each beam is characterized dosimetrically every twelve months (provision 14(b)), the beam monitors are calibrated every two years by a secondary calibration laboratory and their proper operation is verified semi-annually (provision 14(c)), and calibration checks are made of the beam at least weekly for any week that the beam will be used for human therapy (provision 14(a)).

7 (d) Each administration of radiation is in accordance with the written directive (V subject to the tolerances established in provision 11 of MITR Technical Specification #6.5, " Generation of Medical Therapy Beam for Human Therapy."

3-D (e) Any unintended deviations from the written directive shall be identified and evaluated, and appropriate action taken. Such action shall include informing the medical use licensee of the deviation. These reviews shall be performed monthly for any month in which human therapy was conducted. For each

! patient case reviewed,it shall be determined whether the administered total j fluence, fluence per fraction, treatment site, and overall treatment period were as specified in the written directive. In the event of any deviation from the written directive, the licensee (MIT) shall identify its cause and the action required to prevent recunence. These actions may include new or l revised policies, new or revised procedures, additional training, increased l supervisory review of work, or other measures as deemed appropriate.

Corrective actions shall be implemented as soon as practicable.

4. Program implementation: The following practices shall be observed in order to y ensure proper implementation of the quality management program:

! (a) A review shall be conducted of the quality management program. This j review shall include, since the last review, an evaluation of:

(i) A representative sample of patient administrations, (ii) All recordable events, and (iii) All misadministrations.

l The objective of this review is to verify compliance with all aspects of the quality management program. For purposes of this review, the term

' representative' in statement (i) above is defined as 100% sampling up to twenty patients; a sample of twenty for twenty-one to one hundred patients, and 20% sampling for more than one hundred patients, In order to ,

eliminate any bias in the sample, the patient cases to be reviewed should be j selected randomly. ;

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(b) The procedure for conducting the above review is as follows: I l

(i) The review shall be performed by the Director of the MIT Radiation Protection Program or his designate.

(ii) The review shall be performed annually.

(iii) Patient administrations selected for review shall be audited to determine compliance with each of the requirements listed in l paragraph (3) above.

l (iv) The review shall be written and any items that require further action l shall be so designated. Copies of the review shall be provided to the

, NRL Director and to the MIT Reactor Safeguards Committee who i will evaluate each review and,if required, recommend modifications i in this quality management program to meet the requirements of paragraph (3) above. A copy of these reviews will also be provided to each medical use licensee.

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I\ (c) Records of each review, including the evaluations and findings of the review, shall be retained in an auditable form for three years.

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(d) The licensee (MIT) shall reevaluate the Quality Management Program's O policies and procedures after each annual review to determine whether the program is still effective or to identify actions required to make the program I more effective. j

5. Response to Recordable Event: Within thirty days after the discovery of a l recordable event, the event shall be evaluated and a response made that includes:

(a) Assembling the relevant facts, including the cause; (b) Identifying what,if any, corrective action is required to prevent recurrence; and (c) Retaining a record, in an auditable form, for three years, of the relevant ,

facts and what corrective action,if any, was taken.

A copy of any recordable event shall be provided to the affected raedical use licensee.

6. Records Retention: The following records shall be retained:

(a) Each written directive for three years; and (b) A record of each administered radiation therapy where a written directive is ;

required in paragraph (3(a)) above, in an auditable form, for three years after the date of administration.

7. Program Modification: Modifications may be made to this quality manaEement program to increase the program's efficiency provided that the program's effectiveness is not decreased. All medical use licensees shall be notitied of any

[ modifications and provided with a copy of the revised program. The licensee .

(MIT) shall furnish the modification to the NRC (Region I) within 30 days after the modification has been made.

8. Report and Surveillance Frequencv: Any report or other function that is required to be performed in this Quality Management Program at a specified frequency shall be performed within the specified time interval with:

(a) a maximum allowable extension not to exceed 25% of the specified surveillance interval, unless otherwise stated in this Quality Management Program; (b) a total maximum combined interval time for any three consecutive surveillance intervals not to exceed 3.25 times the specified surveillance

. interval.

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!. 9. Definitions:

i l (a) The term 'BNCT physician authorized user' means a medical physician

authorized by the medical use licensee's radiation safety committee to act as

{ an authorized user for BNCF on humans.

i (b) The term 'cenified medical physicist' means a medical physicist certified in i' either radiological physics or therapeutic radiation physics by the American Board of Radiology, or in therapeutic radiation physics by the American

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o Board of Medical Physics and who also has specific training in neutron dosimetry and neutron beam capture therapy. .

10. Applicability: This Quality Management Program applies solely to the generation of medical therapy facility beams for the treatment of human subjects. It does not apply to any other use of the medical therapy facilities and/or their beams. Repons and surveillances listed in this specification are required only if human therapy was conducted during the referenced interval.

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ML20199H266

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