ML19224B263
| ML19224B263 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 09/28/1977 |
| From: | Metropolitan Edison Co |
| To: | Mullinix W NRC/IE |
| References | |
| 1642, TM-0093, TM-93, NUDOCS 7906140311 | |
| Download: ML19224B263 (34) | |
Text
'
N i
'IMI DOCUMENTS
~h DOCUMENT NO:
COPY MADE ON f
OF DOCUMENT PROVIDED BY METROPOLITAN EDISON COMPANY.
Wilda R. Mullinix, NRC
.A 79061403ri 195 120 e
Revision 1
1642 THREE MILE ISLAND NUCLEAR STAilOW AST 0 40T REMOVE STATION HEALTH PHYSICS PROCEDURE 1642 OPERATION AND CALIBRATION OF THE THERMOLUMINESC a uGS MtTRY SYSTEM Table of Effective Pages CONTROLLED COPY Pace Date Revision Pace Date R evision Paae Date Revision 1.0 03/28/77 0
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50.0 75.0 Unit 1 Staff Reccr mer de 'Aporoval Unit 2 Staff Reco meads Approval Approval Date Approval
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Date Cogjzan%/pt.Weed Cogn zanyle[t. tiead Unit 1 PORC Recommends Approval Unit 2 POR Rec mmends Approval
>0 Date Ybdl7 7 M
Date 2
2 y, Chairman of PORC
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Chairman of PORC ff
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PORC comments of included PORC comments of included (date)
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Mgr., Operational Quality Assurance Unit Superintendent f
n-1642 Revision 0 03/28/77 THREE MILE ISLAND NUCLEAR STATION STATION HEALTH PHYSICS PROCEDURE 1642 OPERATION AND CALIBRATION OF THE THERM 0 LUMINESCENT DOSIMETRY SYSTEM 1.0 PURPOSE The purpose of this procedure is to describe the techniques and prccesses required in the operation of the Thermoluminescent Dosimetry TLD) system for personna! r.J areas at Three Mile Island (TMI).
1 2.0 DISCUSSION The TLD system in use at TMI is a useful, accurate, and dependable system for assessing the dose to personnel and areas from Beta, Gamma, or Neutron radiations.
TLD's are essentially linear in response to radiation, tissue equivalent and dose rate indep;ndent.
The useful gamma range is from 10 mR to 10,000R, at which time the indicated exposure is supra-linear, therefore, conservative. The 5
Beta response range is 40 m Rad to 10 m Rad.
Beta and Neutron exposures require correction factors to be applied to the indicated reading to obtain dose in m Rad or m Rem.
The system as installed, after loading, requires minimal superv.ision and will process approximately 250 cards at a time.
In the event of a " fault" the system stops itself, and displays an audible and visual alarm and requires operator action to resume operation.
Calibration includes use of selected " standards" cards and allows for correction of fading of dose information.
Quality Assurance will be provided by regular evaluation of selected cards with known exposures both at TMI and
~
by an independent organization.
Output is recorded by teletypewriter and punched paper tape.
1.0
1642 Revision 0 03/28/77
3.0 REFERENCES
3.1 Harshaw-Chemical Company Instruction Manuals 3.2 AP-1003 Radiation Protection Manual 3.3 HPP 1760 Operation and Calibration of Eberline RAD-0WL R0-1 3.4 HPP 1759 Operation of Victoreen Condenser R meter 3.5 HPP 1753 Operation and Calibration of Eberline PNR-4 3.6 Evaluation of Fast Neutron Dose Equivalent Using the Thermal Neutran Response of LiF TL Material.
Dale E. Hawkins 1976 3.7 HPP 1636 Handling of #64-764100 mci Cs-137 Calibrator 3.8 HPP 1640 Personnel Dosimetry, Irsurance, A linistration and Record Keeping.
3.9 Hewlett-Packard Model 92008 Users Manual 3.10 HPP 1643
4.0 EQUIPMENT
4.1 Model 2271 TL Detector / Dosimeter Identifier 4.2 Model 2271 card loader 4.3 Model 2271 card receiver 4.4 Model 2000B Auto Integrating Picoammeter 4.5 NL-30T comparator 4.6 NE-20T Teletype Interface 4.7 Teletypewriter and Tape Punch 4.8 RAD-0WL-1 4.9 Condenser R-Meter 4.10 Eberline PNR-4
-t 4.11 100 mci-Cs-137 Source 4.12 TLD Cards (Beta-Gamma, Neutron-Gamma)
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l95 123
r 1642 Revision 0 03/28/77 4.13 Card Holders (Badge) for above cards 4.14 N Gas Supply 2
4.15 Stop Watch 4.16 Natural Uranium Slab Calibrated Beta Source 4.17 Hewlett-Packard Model 92008 5.0 OPERATING INSTRUCTIONS 5.1 Description of Controls 5.1.1 Front Panel Model 2271 D/D1 5.1.1.1 START pushbutton - An illuminated pushbutton for manually starting system operation. A manual START overrides a STOP.
If conditions for starting system are not met, START command is rejected.
5.1.1.2 STOP pushbutton - An illuminated pushbutton for manually stopping system operation. A manual STOP overrides a START.
Automatic mode start signal is disabled at beginning of following card sequence.
5.1.1.3 HOLD pushbutton - An illuminated pushbutton for instantaneously stopping system operation.
This pushbutton has push-ON/ push-0FF action.
5.1.1.4 READ 1 pushbutton - An illuminated pushbutton for manually initiating TLD 1 reading sequence during manual mode operation.
If conditions for reading TLD 1 are not met, READ 1 command is rejected.
5.1.1.5 READ 2 pushbutton - An illuminated pushbutton for manually
-j initiating TLD 2 reading sequence during manual ' mode operation.
If conditions for reading TLD 2 a're not met, READ 2 command is rejected.
5 _ h S kl... -.?
3.0
s 1642 Revision 0 03/28/77 5.1.1.6 IDENT. pushbutton - An illuminated pushbutton for manually initiating TLD card ID number reading sequence during manual mode operation.
If conditions for reading ID number are not met, IDENT. command is rejected.
5.1.1.7 BACKGR. pushbutton - An illuminated pushbutton for manually initiating background reading sequence dur.ag manual mode operation.
If conditions for reading background are not met, BACKGR. command is rejected.
5.1.1.8 REF. LT. pushbutton - An illuminated pushbutton for manually initiating sensitivity check reading sequence during manual mode operation.
If conditions for reading sensivity check are not met, REF. LT. command is rejected.
5.1.1.9 SEQUENCE SELECTOR ro',ary steitch - Five position rotary switch selecting syste:1 mode of operation. Modes of operation are manual mode (MANUAL), automatic mode (TLD 1, TLD 2, TLD 1 &
2), and external program made (EXT. PROG. ).
During manual mode, system operation is controlled by READ 1, READ 2, IDENT.,
BACKGR. and REF. u pushbuttons.
During automatic mode, system operation is controlled automatically according to SEQUENCE SELECTOR switch position.
During external program mode, system operation is controlled by an external controller or by manual mode pushbuttons.
5.1.2 Rear Panel Model 2271 5.1.2.1 CLEAR pushbutton - Pushbutton manually forces sys+em control f
to beginning of next card sequence.
CLEAR must'be pressed for each control circuit to step through remaining sequence.
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195 125 1l 4.0
1642
^
Revision 0 03/28/77 CAUTION:
Do not press clear pushbutton for card fault until faulted card has been released from system.
5.1.3 Inside Front Door Model 2271 5.1.3.1 CARD RELEASE toggle switch - Two position switch retracts reference light and card channel T-bars when in CARD RELEASE position.
NORMAL position allows normal T-bar operation.
5.1.3.2 LIGHT TEST toggle switch - Momentary switch lights all front panel display and pushbutton lamps when held in up position.
5.1.4 Interpreting Panel Display Indications of Model 2271 The Model 2271 TL D/DI is equipped with a display on the front panel presenting system status information.
This information is presented in two ways.
One presentation gives the normal conditions (OPERATION:
Green) of the system status.
The other presentation gives the abnormal conditions (FAULT:
Red) of the system status.
Fault conditions stop system operation, and sounds an audible alarm. When this condition (RED) occurs refer to Section 5.6, Fault Correction. The front panel display is interprated as follows:
Operation:
(GREEN)
NO CARD No TLD card is in system.
NORMAL - A properly oriented TLD card is in feed slot.
TLD1
- TLD card is in position for reading TLDl.
TLD2
- TLD card is in position for reading TLD2.
BACKGROUND - A special card for providing a dark current measurement is in feed slot.
SENS. CHECK - A special card for 'providing sensitivity check is in feed slot.
5.0 195 126--
~.
1642 Revision 0 03/28/77 I.D. - TLD card is in position for reading identification number.
Fault:
(RED)
REVERSED - TLD card is improperly oriented in feed slct.
DATA
- Numeric data transmitted to output device has not been properly acknowledged, or Model 20008 Pico-ammeter Toggle switch off.
I.D.
- Two or more parity errors exist in TLD card identi-fication number.
CARD
- TLD card has not arrived at card position required for next operation.
HEATER MOVE - Heater hot finger movement for reading dosimeter has not occurred.
H.V.
- Photomultiplier tube high voltage is not within set limits, or card release switch left on.
TEMP.
- Maximum heater hot finger temperature during dosimeter reading is not with set limits.
N_2
- Inert gas flow is below limit.
5.2 Normal Operations 5.2.1 Loading the Card Loader Cartridge:
With cartridge mounted on auto card loader:
- 5. 2.1.1 Ensure spring loaded cables are loosened from card follower and retracted into AUTO card loader.
5.2.1.2 Insure two small metal latches at front of cartridge are in the in, position.
5.2.1.3 Move card follower plate to rear of cartridge.
Load 2 or 3
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Background Sensitivity (B/S) cards with face to front and S
='
195 127
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6.0 e
1642 Revision 0 03/28/77 position on top left, at front of cartridge.
Load desired number of cards to be read with face of card to front of cartridge and TLD-2 to top left when facing the cartridge.
NOTE 1:
Insert a B/S card after approximately every 50 TLD cards in the cartridge, and 2 B/S cards as the final cards in the cartridge.
NOTE 2:
If cartridge is detached from the AUTO card loader follow step 5.2.1.3 and then attach with guide pins in proper holes and thumb screws finger tight.
5.2.1.4 Pull cables by T bars and attach on card follower ears on both sides.
5.2.1.5 Insure machine set up for normal operation.
5.2.1.6 Pull metal latches to out position.
5.2.2 Card Receiver Operation 5.2.2.1 Insure a card receiver cartridge is properly attached in the card receiver.
5.2.2.2 Ensure the clip latches on both sides of the front of the cartridge are in the MID position.
5.2.2.3 Ensure the card follower is in the fully forward position.
5.2.2.4 Close the card receiver drawer.
5.2.2.5 Pull the drawer lock knob and turn counterclockwise approximately turn.
5.2.2.6 Ensure ready light is on.
NOTE:
Receiver will now accept cards automatically until h
either FULL or JAMMED.
In either of which cases the detector will cease operation and the Full / Jam light
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will come on.
If this happens see section 5.6 Fault Correction.
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7.0
1642 Revision 0 03/28/77 5.2.3 Normal Automatic Operation Check Check that all conditions and/or switch settings are in proper position or as follows:
5.2.3.1 Model 2271 5.2.3.1.1 Iasure sufficient N2 g s supply available in cylinder at about 2 SCFH flow rate or sufficient to clear N 2 f ult light.
(Approximately 500 pounds of cylinder pressure is required for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> operation).
5.2.3.1.2 Insure SE0VENCE SELECTOR is in the TLD 1&2 position.
5.2.3.1.3 Insure card receiver cartridge has room to receive anticipated load of machine run and is set up in accordance with 5.2.2 above.
5.2.3.1.4 Insure card receiver DRAWER LOCK is in lock position (counter-clockwise) and Ready light is On.
5.2.3.2 Model 2000 8 5.2.3.2.1 Insure Period SEC switch set at 10.
5.2.3.2.2 Insure METER switch at CURRENT.
5.2.3.2.3 Insure Rance AMP switch set at AUTO.
5.2.3.2.4 Insure Toggle set at X 1.
5.2.3.2.5 Check Hiah Voltace Pot setting against previous operating day setpoint noted on Form 1642-1.
If it is different, and there is no entry in log for an explanation, report to Rad. Prot.
e Foreman.
5.2.3.2.6 Insure Power Otl toggle switch in UP position.
NOTE:
If this switch is not in the UP_ position allov 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> warm up time before normal operation.
8.0 m eme em 195 129
1642 4
Revision 0 03/28/77 5.2.3.3 NQ-60A & NE-20T-TTY Interface 5.2.3.3.1 Insure MODE switch is in the Remote Position.
5.2.3.3.2 Insure Control switch is in the Normal Position.
5.2.3.3.3 Set UPPER and LOWER digital comparator as desired or as per Rad. Prot. Foreman instructions.
CONTROLS UPPER LIMIT Switch Five thumbwheels to set desired upper limits and range.
LOWER LIMIT Switch Five thumbwheels to set lower limits and range.
UPPER LIMIT Indicates when data is higher tnan upper limit Indicator Lamp setpoint.
LOWER LIMIT Indicates when data is lower than Lower limit setpoint.
Indicator Lamp CLEAR Pushbutton Remove inhibit signal from Comparator.
CAUTION:
DESIRED LIMITS MUST BE SET USING THE SMALLEST POSSIBLE RANGE.
NOTE:
If upper or lower alarm setpoint is exceeded, machine operation will stop and alarm will sound.
Depress alarm CLEAR and contact Rad. Prot. Foreman.
5.2.3.4 (Telet,pewriter) 5.2.3.4.1 Insure LINE/0FF/ LOCAL switch in LINE position.
5.2.3.4.2 Depress ON bJttCn on Taj.e Punch.
Insure sufficient paper and tape are available to record results of TLD evaluation.
5.2.4 Startup of System E.2.4.1 Depress START button.
,I 5.2.5 Data Interpretation (Refer to Figure 1) 5.2.6 Computation of Mean and Standard Deviation Consult Hewlett-Packard users manual of standard pr.ograms:
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9.0
---i 195~ i 3h0
1642 Revision 0 03/28/77 The Program Number is 70801.
Complete instructions for its use are provided.
Enter computation on Form 1642-1 for step 5.4.4 only.
n Mean = 1 I r of TLD-2 Readings n i=1 where n number of readings r = TLD reading 5.3 Instrument Shutdown 5.3.1 Turn LINE/0FF/ LOCAL switch to 0FF position on TTY.
5.3.2 Move POWER toggle switch to down position on NQ60A.
5.3.3 Turn N2 Cylinder main valve OFF.
NOTE:
Do Not secure POWER ON toggle switch on Model 2000 B.
5.4 Machine Calibration NOTE:
The following should be done on or near each badge exchange date.
5.4.1 ZERO eleven (11) of the selected standards and expose ten (10) of them in card holder badges to 100 mrem dose in accordance with 5.5.2.1.
5.4.2 Send five (5) cards plus one (1) control to Harshaw Chem. Co.
for evaluation.
5.4.3 Allow 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> delay after exposure for fade correction.
Store cards in shield cave between exposure and reading.
10.0 e.
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195~13r I
1642 Revision 0 03/28/77 5.4.4 Read five (5) cards and calculate mean of TLD-2 readings.
See Step 5.2.7.
Enter TLD-2 readings on Form 1642-1.
5.4.5 Obtain current sensitivity setting of machine by reading a B/S card.
5.4.6 Calculate new sensitivity setting for 2271 by following formula.
Enter calculations and results on Form 1642-1.
EXPOSURE CURRENT y
= NEW SENSITIVITY TLD-2 MEAN SENSITIVITY 5.4.7 Adjust the high voltage of the Photomultiplier tube to obtain a corrected sensitivity reading by repeating B/S card readings, and high voltage adjustments.
Enter new high voltage setting on Fonn 1642-1.
5.4.8 The independent evaluation of the other 5 cards should corroborate the exposure dose administered to the cards.
If it does not, notify Radiation Protection Foreman / Supervisor of discrepancy.
NOTE:
The acceptance criteria for the above is that the mean of the TLD-2 readings of the 5 cards is within
+ 25% of the exposure amount.
5.5 TLD Card Tests 5.5.1 Selection of Standards 5.5.1.1 Zero all cards and expose in card holders to 100 mrem.
5.5.1.2 Allow 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> delay for fade correction.
5.5.1.3 Read exposed cards.
5.5.1.4 Calculate Mean of TLD 2 readings.
(Refer to 5.2.7).
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- 5. 5.1. 5 Select standards (approximately 20) from those cards with TLD-2 reading within 2.0% of the mean.
11.0 195 132
1642 Revision 0 03/28/77 5.5.1.6 Set these standards aside in the shield cave for machine calibration and quality assurance testing.
5.5.2 Card Test and Standard Irradiation NOTE:
Standards cards will be irradiated monthly to check instrument calibration, ans assure quality assurance of dose information.
All cards will be submitted to a test irradiation annually to assure retention of accuracy.
5.5.2.1 Gamma Exposure 5.5.2.1.1 To remove background exposure received since last use, zero carss to be exposed by passing tnrough Model 2271 and reading both TLD-1 and TLD-2.
5.5.2.1.2 Insert TLD Cara in Badge (s) in proper orientation with TLD 1 behind open window and TLD-2 behind aluminum window.
5.5.2.1.3 Proceed to Heat Exchanger Vault, place exposure board on flat surface away from other radiation sources, and ten feet from any scattering surface.
5.5.2.1.4 Stand TLD Badges to be exposed upright and equidistant from the center of the board.
(See Figure 2).
NOTE:
Measurements'in Feburary 1975 indicate an exposure time of 22.35 minutes at'30 cm. deposites 100 mR of Gamma dose on TLD-2 exposed in the Badge.
This should be checked annually and adjusted as required for source decay in accordance with 5.5.2.1.10.
5.5.2.1.5 Remove the Cs-137 source from-the source storage container, and immediately place in the source hole in center of exposure board, and simultaneously start stopwatch.
12.0 2
195 133'
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1642
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Revision 0 03/28/77 5.5.2.1.6 Observe stopwatch until prescribed exposure time for desired exposure has elapsed and quickly return source to source storage container.
5.5.2.1.7 Repeat steps 5.5.2.1.1 through 5.5.2.1.6 as required for additional cards to be exposed.
NOTE:
Approximately 40 ca~rds may be exposed at a time in this manner.
CAUTION: Do not permit unintentional exposure to cards from this or other sources of radiation.
5.5.2.1.8 Return exposed cards to TLD Room and remove cards from badges.
5.5.2.1.9 Read the exposed cards 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after exoosure, to permit fade correction.
5.5.2.1.10 Recalculate exposure rate of TLD cards at 30 cm distance at least annual.ly by the following steps:
NOTE:
A calibrated R0-1 meter on the integrated scale may be used if the Condenser R meter is not available.
5.5.2.1.10.1 Zero the 0.250 R condenser R meter.
5.5.2.1.10.2 Stand the 0.250 R condenser R meter with it's nidline at 30 cm from the source on the exposure board.
5.5.2.1.10.3 Place the 100 m Ci source in the source hole in the center of the board, and simultaneously start the stopwatch.
5.5.2.1.10.4 Stop the stopwatch and remove the source to the source storage container after elapsed time results in 100 mR exposure.
Record res0lts on Form 1642-2.
b NOTE:
Several trials may be required to' determine exact exposure time.
13.0
_ ~.. g
1642 Revision 0 03/28/77 5.5.2.2 Beta Exposure - Establishing Beta Correction factor annually and at receipt of new cards.
5.5.2.2.1 To remove background exposure received since last use, zero cards to be exposed, by passing through Model 2271 and reading both TLD-1 and TLD-2.
5.5.2.2.2 Insert cards to be exposed into badges with TLD-1 behind paper window and TLD-2 behind aluminum window.
Calculate exposure time in accordance with following equation:
Beta Exposure MRAD - Exposure rate (MRAD) x hours exposed hour NOTE:
Exposure rate is available in source certificate file.
Record results on Form 1642-2.
5.5.2.2.3 With cards in badge, expose the cards in groups to the source, face in contact with the source for time required to obtain desired exposure.
Time exposure with stnpwatch.
5.5.2.2.4 Remove TLD badges from source.
5.5.2.2.5 When all exposures have been comp eted, return source to storage container.
NOTE:
Steps 5.5.2.2.2 through 5.3.2.2.4 should be epeated as required until all desired cards have been exposed.
5.5.2.2.6 Remove cards from badges.
Store in shield cave for 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> to permit fade correction.
5.5.2.2.7 Read the cards by normal procedure as described in section 5.0.
]
5.5.2.3 Beta Correction Factor 14.0
,m M
eW
=e6 e
195 135:
1
^
1642 Revision 0 03/28/77 NOTE:
This function may be performed in conjunction with the Beta calibration above.
5.5.2.3.1 Take 5 standards cards in holders and expose face down on calibrated uranium-slab source to obtain 100 MRAD exposure.
5.5.2.3.2 Remove from slab after elapsed time and allow 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> delay for fade correction.
Store the cards in shield cave during delay.
5.5.2.3.3 Read the cards by passing through the 2271 card reader.
Refer to 5.0.
5.5.2.3.4 Calculate the mean of the TLD-1 readings.
Refer to 5.2.7.
5.5.2.3.5 Calculate the mean of the TLD-2 readings.
Refer to 5.2.7.
5.5.2.3.6 Calculate the Beta correction factor (b) using the formula:
(R R) b
=
1 2
0
'B Where:
b = correction factor to be applied to TLD-1 readings, after TLD-2 is subtracted from it, to obtain Beta dose in MRAD.
R) = Mean of TLD-1 readings.
1.15 =
Constant to correct for open window lack of electronic equilibrium R
Mean of TLD-2 readings
=
2 0
Beta exposure applied to TLD cards above.
=
B 6
15.0
~~
. 195 136...
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a
1642 Revision 0 03/28/77 t.0TE :
Beta dose for unknown exposures is calculated by the formula:
(R
- 1.15 R)
D
=
B
_1 2
b 5.5.2.3.7 Enter Beta correction factor on Form 1642-3.
5.5.2.4 Neutron Correction Factor 5.5.2.4.1 Obtain 6 type NG-67 cards and zero by established method.
Install the cards in holders in normal orientation.
5.5.2.4.2 Submit these five cards plus the control to a commercial service exposure facility
- wito instructions to obtain a certified thermal neutron exposure in the 0-200 mrem range.
Exposure is to be performed with phantom.
5.5.4.3 Upon return to TMI, evaluate the exposed cards and control in accordance with section 5.2.3.
5.5.2.4.4 Calculate mean of TL-1 and mean of TL-2 of exposed cards in accordance with section 5.2.7.
Subtract the control card values from TL-1 and TL-2.
5.5.2.4.5 Calculate thermal neutron correction factor in accordance with formula:
th TL) - 1.26TL2 M
=
u
~~
m Where M
= Neutron correction factor h
TL]
= Corrected Mean of TL-1 readings 1.26 = Sensitivity and gamma correction for TL-1 O
16.0 195 1372r 2 z-3
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1642 Revision 0 03/28/77 TL
= Corrected mean of TL-2 readings 2
D
= Thermal neutron exposure of step 5.5.2.4.2 m
NOTE:
M is normally approximately 71.
th 5.5.2.4.5 Conduct a thermal neutron (with bare BF-3 tube on neutron rem-meter) and total neutron survey (with BF-3 tube in rem-meter in normal configuration) survey of the reactor containment in areas in which personnel may be exposed to neutrons.
Take one reading of each type at. cach location.
5.5.2.4.6 Correct the thermal neutron (bare probe) readings by dividing by 80.
5.5.2.4.7 Obtain the mean of the ratios of the total neutron dose rate to the corrected thermal neutron dose rate.
(I.E. - Total neutron dose rate + thermal neutron dose rate 80 Call this value d NOTE:
Unknown neutron exposures should be calculated as fillows:
Neutron Dose =
(TL) - 1.26 TL )
XN 2
tith Where: Symbol descriptions are as above.
5.5.2.5 The values Mth and N should be retested af ter each refueling or at least annually and the results of N entered on Form 1642-3.
5.6 Fault Correction 5.6.1 N g 5.6.1.1 Depress hold button and replace N2 :ylinder.
5.6.1.2 Adjust regulator to allow approximately 2SCFH.
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17.0
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1642 Revision 0 03/28/77 5.6.1.3 Depress hold button to restart readings.
5.6.2 Card 5.6.2.1 Depress HOLD button 5.6.2.2 Depress STOP button 5.6.2.3 Open Model 2271 door front 5.6.2.4 Pull card receiver drawer lock knob and turn approximately k turn clockwise to open.
5.6.2.5 Move toggie switch to CARD RELEASE POSITION. Catch the card coming out the card chute.
5.6.2.6 Return card release to normal.
5.6.2.7 Inspect card carefully, clean carefully with methanol to remove any trace of glue, dirt, etc.
5.6.2.8 Remove cables from card loader cartridge being careful not to permit a card to fall into the reader.
- 5. 6. 2. 9 Manually insert fault card into reader.
5.6.2.10 Set cartridge card latches to IN position.
5.6.2.11 Close card receiver drawer and turn drawer lock counter clockwise.
5.6.2.12 Close door on front and latch.
5.6.2.13 Reattach cables on card leader follower, and pull cartridge and latches to OUT position.
5.6.2.14 Depress HOLD button.
5.6.2.15 Depress rear reset button, and start the system through the sequence until the next card reading is ready.
MAKE A NOTE of the CARD NUMBER on the printed output.
5.6.2.16 Depress START button.
~
5.6.2.17 Clear digital comparator alarm if required.
18 0
=
195-b39
1642 Revision 0 03/28/77 5.6.3 Full / Jam Light 5.6.3.1 Depress HOLD and STOP buttons.
5.6.3.2 Open front cover of Model 2271.
5.6.3.3 Visually check for card stuck at entrance to card receiver.
5.6.3.4 If card is stuck at this point, carefully use wood end of Q tip or ott.er inst. ument to move card up its path.
NOTE:
As card is pulled up, the card receiver ram will cycle.
Do not permit the card to drop.
5.6.3.5 Pull and turn the drawer / lock knob to the clockwise position.
5.6.3.6 Open the card receiver drawer to permit the card to drop behind the card follower.
5.6.3.7 Closely inspect the card for nicks, dirt, glue, bends, etc.,
which may have stopped card at this point.
5.6.3.8 Clean, smooth, as required and place card in receiver in it:
proper position.
NOTE:
If the problem is that the card receiver cartridge is full:
Remove sufficient cards from card receiver cartridge to accommodate ~ cards remaining in card loader cartridge to be processed, or replace with an empty cartridge.
5.6.3.9 Ensure card follower is forward against last card in cartridge and cards are straight.
5.6.3.10 Close drawer and pull and turn drawer / lock knob to counter clockwise position.
5.6.3.11 Check that Ready light comes on.
5.6.3.12 Close front cover of 2271 and depress Hold button.
5.6.3.13 Depress Start button.
~
~ ~ ~
195.L40..
i 19.0
~
1642
~
Revision 0 03/28/77 5.6.4 H.V. (High Voltage) 5.6.4.1 Depress Hold Button 5.6.4.2 Open Front Panel of Model 2271 and CHECK Card release toggle switch in down position.
If not, put it there, close front panel & depress HOLD pushbutton.
As required consul t Rad.
Prot. Foreman and Model 2271 Detector / Dosimeter Identifier Instruction Manual.
5.6.5 Reversed 5.6.5.1 Depress HOLD button.
- 5. 6. 5. 2 Remove spring loaded cables from card loader cartridge card foll'ower, being careful not to permit another card to enter reader.
5.6.5.3 Slide cards remaining to be read one to two inches toward rear of cartridge to allow room.
5.6.5.4 Manually extract reversed card from card feed slot.
5.6.5.5 Replace card in feed slot with front facing forward and dosimeters along lef t edge.
5.6.5.6 Set card cartridge latches to E position.
5.6.5.7 Slide cards remaining to Le read forward and connect cables on card loader follower ears.
5.6.5.8 Pull card cartridge latches to OUT position.
5.6.5.9 Depress HOLD button.
5.6.6 Data 5.6.6.1 Write down TLD-1 Reading from Model 2000 B_ Display.
5.6.6.2 Turn NQ-60 Power toggle switch to UP position..
5.6.6.3 Clear FAULT with Model 2271 Rear Panel CLEAR pushbutton.
5.6.7 Temp
~ ~ ~
~
~ ~ ~
.e 20.
195 14 F
1642 Rcvision 0 03/28/77 5.6.7.1 Depress HOLD button.
5.6.7.2 Consult Model 2271 Detector / Dosimeter Identifier Manual.
5.6.8 Heater Move 5.6.8.1 Depress HOLD pushbutton and contact Rad. Prot. Foreman.
5.6.9 I.D.
5.6.9.1 Depress HOLD pushbutton.
5.6.9.2 Pull and turn card receiver DRAWER LOCK knob to clockwise position.
5.6.9.3 Open Model 2271 front panel and move CARD RELEASE toggle switch to UP, position, catching card as it comes through chute.
5.6.9.4 Return toggle switch to DOWN position.
5.6.9.5 Close FRONT PANEL to model 2271.
5.6.9.6 Inspect faul.t card for dirt in ID light ' ale matrix and clean as necessary.
5.6.9.7 Note Card Number 5.6.9.8 Insert card in card receiver: cartridge in next position.
5.6.9.9 Insure cards are straight and card follower is forward and snug against rear cards in cartridge.
5.6.9.10 Close card receiver drawer and pull and turn DRAWER LOCK knob to counterclockwise position.
5.6.9.11 Type manually the fault card number on the teletypewriter.
5.6.9.12 Depress HOLD pushbutton.
5.5.9.13 Depress rear panel CLEAR, pushbutton.
b 5.7 TLD Card and Card Track Cleaning 5.7.1 TLD Card Cleaning
~~~-
~-
21.0
~
~
~
~ 195 F42 -
3
~
1642 Revision 0 03/28/77 NOTE:
Each TLD card must be cleaned carefully and thoroughly prior to each evaluation.
5.7.1.1 Dip a cotton swab into a small container of methanol.
Shake excess methanol off SWAB.
5.7.1.2 Wipe thoroughly all external surfaces of the iLD card paying particular attention to the edges and back.
5.7.1.3 Visually examine the card for glue specks, bends, etc.
5.7.1.4 Slightly bent TLD cards may be straightened by placing on a hard flat surface and pressing manually with moderate pressure.
5.7.2 Reader Card Track Cleaning 5.7.2.1 Place POWER toggle switch to down position on the Model NQ60A.
5.7.2.2 Open the front cover on the Model 2271 Reader / Identifier.
5.7.2.3
~ Place the CARD R_ELEASE switch in the UP_ position.
5.7.2.4 Loosen the two thumbstrews on the inside cover.
5 7.2.5 Open cover.
- 5. 7. 2. 6 Dip the wooden end of the cotton swab in method for a few seconds.
Dip this end in the jar of Magnesium 0xide (M 0) g powder.
5.7.2.7 Press and hold the solenoid bar on the hot finger to make it more accessible and visible.
5.7.2.8 With the M 0 powdered end of the cotton swab scrub the square g
surface of the hot finger until all burned on material is removed.
Wipe thoroughly with cotton swab dipped in metharol.
5.7.2.9 Hold a ruler c-similar flat piece of material along the
-j inside front panel to stop the T-bars and move the CARD RELEASE switch to the H.V. position.
22.0
~
195J 43 3
4 I
1642 Revision 0 03/28/77 5.7.2.10 Noting exactly the orientation, remove each T-bar and spring, one at a time and clean thoroughly with methanol on a cotton swab.
5.7.2.11 Using a clean cotton swab with metha:iol, swab out the hole for the T-bar.
Replace the T-bar in the exact original orientation.
5.7.2.12 Gently clean the PM tube light window and card ID light with a dry cotton swab.
5.7.2.13 Dip cotton swab in methanol, shake off excess and, starting at the top, clean thoroughly, both surfaces (front and back) of the card track.
Pay particular attention to the back surface.
Replace cotton swabs when sailed.
5.7.2.14 Place the CARD RELEASE switch in the ug position and isnure each T-bar is in the retracted position.
5.7.2.15 Close the.inside front panel and tighten the thumb screws fingertight.
5.7.2.16 Place the CARD RELEASE switch in the down position and close the front panel to the Model 2271.
5.7.2.17 Place the POWER toggle switch in the u_p_ position on the Model NQ60A.
5.7.2.18 Allow a few minutes for the PM tube to stabilize.
5.7.2.19 Read approximately 20 cards from which exposure data is not required.
This burns the " Shine" from the hot finger.
Read 2 B/S cards and check that the Background and Sensitivity values are in the normal range.
If so, the machine is ready for normal operation.
NOTE:
The hot finger should te checked and cleaned as necessary after each full card cartridge or approximately 250 cards are processed.
I95 144 2
23.0
1642 Revision 0 03/28/77
~
E.8 Routine (Monthly) TLD Functions NOTE:
Each month of at the end of each exposure period the following steps should be performed in the sequence indicated.
If, for any reason the sequence cannot le followed exactly, notify the Radiation Protection Supervisor /
Foreman of the reason.
5.8.1 On or before the badge exchange date perform quality assurance check in accordance with HP 1643.1, Section 5.1.
5.8.2 Obtain the AREA and STATION TLD badges from the lead cave storage, re-zero and exchange vith the TLD badges at each location.
NOTE:
400XXX series badges are used during even number months and 410XXX series badges are used during odd
. number months.
5.8.3 On the first day of each month, or on the day determined by the Radiation Protection Supervisor, excaange ali the permanent pt rsonnel TLD's, except those who have terminated during the exposure period.
Pick up all temporary badges issued (300 series), all neutron and extremity badges.
NOTE:
A list of personnel who have terminated during the exposure period should be available on the badge exchange date.
Do not replace the terminated personnel's badge on the badge rack; however, do pick up the badge which was exposed.
5.8.4 Insure the QA TLD's evaluated and re-exposed by'the specified vendor have been returned and are available.
~
24.0 195 14gs
1642 Revision 0 03/28/77 5.8.5 Remove the TLD card fre n aach badge holder, exercising care to preclude any damage '
the TLD card.
5.8.6 Set aside the bad' "lders (both 100 and 200 series) for terminated per,annel.
NOTE:
It is normally advantageous to arrange the badge holders in easily retrievable order to permit easy finding when returning the TLD card to the badge holder.
5.8.7 Sort each set of TLD cards into sequenti-al numerical order.
5.8.8 Clean each TLD card in accordance with 5.7.1.
5.8.9 Clean the card track and hot finger, if required.
(See 5.7.2).
5.8.10 Arrange TLD cards to be evaluated in the card loader cartridge (s) in the following order:
5.8.10.1 3 8/S cards 5.8.10.2 5 TMI Standards exposed in step 5.8.3.
5.8.10.3 2 B/S cards.
5.8.10.4 5 QA Standards plus control from specified vendor.
5.8.10.5 2 B/S cards.
5.8.10.6 11 Station TLD cards, 400 Series.
5.8.10.7 2 B/S cards.
5.8.10.8 30 AREA TLD Cards.
5.8.10.9 2 B/S cards.
5.8.10.10 All permanent personnel TLD cards (100 or 200 series).
5.8.10.11 All visitors TLD cards (300 series).
}
5.8.10.12 All personnel neutron TLD cards (800 series), if required.
5.8.10.12.1 All personnel extremity TLD cards (700 series); if required.
.]
25.0
- jg
1642 Revision 0 03/28/77 5.8.10.13 Before each TLD card set is evaluated advance 12" of punched tape, and type the following information on the TTY:
5.8.10.13.1 Date and Time.
5.8.10.13.2 flame of Operater.
5.8.10.13.3 A description which includes the exposure start and finish dates: e.g. "the following TLD cards are permanent personnel exposed from 08/01/75 through 08/31/75. The cards are b1ing read on 09/02/75." This entry should be typed between the 8/S cards inserted between sets in the loading sequence.
fl0TE:
Ensure sufficient punch tape and TTY paper are available to accept the data from tne output.
5.8.10.14 After each set of TLD's is evo:uated remove them from the card receiver and reload into the correct badge holder.
f40TE:
Each of the AREA and STATI0fl badge holders is taped to exclude dirt and insects, etc.
5.8.11 Sort all badges and store in the lead cave for issue at next exchange period (except 300 series).
5.8.12 Return all contamination free 300 series visitors badges to the rack in TLD room, for reissue.
Preparation for reissue must include removal of all previous name tags from top of badge and replace witn clean sticker.
Insure legible TLD number on bottom front of badge.
5.8.13 Take the punched paper tape and TTY printout to the Radiation
-[_
Protection Foreman for data processing.
5.8.14 Prepare both TLD cards (100 and 2'00 series) of terminated personnel for reissue.
195 147 i
.1 4
26.0
~.
1642 Revision 0 03/28/77 f(OTE:
TTY printouts and punched tape will be stored for a period of one (1) year.
5.9 tion-Routine TLD Functions tiOTE:
This procedure step is for the reading of TLDs on other occasions than monthly.
i.e., self-reader dosimeter off scale, individual's request or possible high exposure.
5.9.1 Read 2 B/S cards.
If sensitivity is within i 10% of the most recent sensitivity entered on Form 1642-1, continue to next step of procedure.
If sensitivity is not within the i 10%
limit, notify the Radiation Protection Foreman of the discrepancy.
5.9.2 Read the exposed TLD cards.
5.9.3 Return badgas as required.
5.9.4 Take the punched paper tape and TTY printout to the Radiation Protection Foreman for data processing.
5.10 Dosimetry Functions During Wear Period 5.10.1 New Personnel (permanent) 5.10.1.1 Install the correct TLD badge holder (100 or 200 series) for the current month in the correct labeled personnel dosimetry rack 'ocation.
5.10.1.2 Place the TLD badge for the next wear period in the lead cave in the proper numerical group.
5.10.2 New Personnel (Visitor) 5.10.2.1 Insure there is a correctly labeled dosimetry rack location for each visitor TLD badge issued.
5.10.2.2 Ensure each visitor knows where his location is'and that he is required to use it.
~~~
27.0 195 L48
=
/.
1642
- ~
Revision 0 03/28/77 5.11 TLD Form Filing 5.11.1 Form 1642-1 5.11.1.1 Completed monthly 1642-1 forms will be filed in a folder in the TLD room.
NOTE:
All completed forms in excess of the three most recent completed forms should be delivered to the Radiation Protection Foreman / Supervisor.
5.11.1.2 Blank 1642-1 forms will be kept in a separate folder in the TLD room.
5.11.2 Forms 1642-2 and 1642-3.
5.11.2.1 An in-use Form 1642-2 and Form 1642-3 will be filed in separ.te folders in the TLD room until the form is totally filled out.
The filled out forms should be delivered to the Radiation Protection Foreman / Supervisor.
5.11.2.2 Blank 1642-2 and 1642-3 forms will be kept in a separate folder in the TLD room.
O 28.0' T
i 195-149
1642 Revision 0 03/28/77 FIGURE 1 AUTOMATIC MODE SAMPLE DATA PRINT-0UT A
B C
A B
C D
E 0
5527 0
2 0120 1
0 125235 0
5591 0
2 0137 1
0 125223 0
6365 0
2 0135 1
0 125231 0
6548 0
2 9605 0
0 125236 5
0609 0
4 2008 1
0 900000 5
0533 0
4 2980 1
0 900000 0
6923 0
2 1623 0
0 900000 l
l l
ll l
a 1
i TLD-1 TLD-2 Identification KEY:
A.
Type of Data in 0 = TLDl,1 = Re-read TLDl, 2 = TLD2 Following 4 Digits: 3 = Re-read TLD2, 4 = Gain Check, 5 = Dark Current B.
Output Data, Integrated Light Relative to Dose (coulombs)
C.
Position of Decimal Point 0 = 1.234 nc 1 = 123.4 nc (nanocoulombs) in Preceding 4 Digits:
2 = 12.34 uc 3 = 1234. pc (microcculombs)
(Note:
For TLD-2, nc and uc s equal to mrem and rem, respectively).
D.
Identification Number 0 = No Parity Error 1 = One Parity Error - no stop 2 = Two Parity Errors - stop E.
Six Digit Identification Number 29.0
- mp em 195--150-3 2
1642 Revision 0 FIGURE 2 P. u! 0.ri 5 %s i (k-hN '
a!
j t
,. I Li._d !
.I l
l i
-:- -m, N I
N.
/.
NN
/
\\\\
/
\\
/
\\
/
n is u
l so.~cc
+
l l(v.O
,1
- a 1r^
i _. _.,
x.
! .'*:. - i 3 7 g
i.
c t ;..',.. s
/' %./
- p......_.. 1
..w.
l e?/
/'
h p#[
TLD -
-N Eadges s' %w r*
40 per c sure
?
bb Rcd-Owl t.
TLD B;dge Exposure Fccility 30.0 9
HIGH VOLTAGE / SENSITIVITY LOG SHEET
. ~. -
Date TLD 2 READINGS
+
1.
4.
Current High Voltage Setting 2.
5.
3.
COMPUTATION OF Mr. AN AND STAND ARD DEVIATION Formula Computation Results n
{r of TLD 2 readings Mean Mean =
=
Note:
Use Hewlett-Packard with program No.
where "n"is number of readings 70301 to determine results.
Computed by Date/ Time r = TLD reading y
-m
'o a
N
.L CALCULATION OF NEW SENSITIVITY OF MODEL 2271 Formula Calculations New Sensitivity E* U *'
X Current Sens. = New Sensitivity TLD 2 Mean Exposure - HPP 16421 Step 5.4.1 X
=
TLO-2 Mean - See computation above Computed by Date/ Time Current Sens - HPP 1642-1 Step 5.4.5 so ST:
U4
% 5. /J co m Reviewed by D&
Ln rJ New High Voltage Setting Rad. Prot. Foreman / Supervisor i
Form 1642-1 i
.a:
.,'s FORM 1642-2 1642 l
Revis1tn 0 03/28/77 EXPOSURE RATE LOG FOR 1RRADIATING T1.D'S Source Exposure Required Time for Performed By Date Used Distance Exposure Oose Required Dose (Signature) i,-
~
95 153
~
~i Form 1642-2 32.0
a
,s FORM 1642-3 1642 Revision 0 03/28/77 BETA / NEUTRON CORRECTION FACTOR LOG SHEET Beta Date Date Calculated Neutron Date Date Calculated Correction Correction Calculated Due By Calculated Due By Factor Factor a
4 1 95 154
}
Form 1642-3 33.0