ML20080Q967

Responds to Confirmatory Action Ltr 84-03 Re Contamination of Personnel Exceeding Quarterly Extremity Dose Limits. Communications Between Health Physics Personnel Improved as Result of 840118 Overexposure

ML20080Q967
Person / Time
Site:	Pilgrim
Issue date:	02/15/1984
From:	Harrington W BOSTON EDISON CO.
To:	Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
BECO-#84-028, BECO-#84-28, CAL-84-03, CAL-84-3, NUDOCS 8402270271
Download: ML20080Q967 (21)

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BOSTON E'DIEDN COMPANY B00 BovLsTON STREET WasTON, MASSACHUSETTS 02199 WILLIAM D. HARRINGTON ocusen viss meessoast em m.

February 15, 1984 BECo Ltr. # 84-028 Mr. Richard h. Starostecki, Director Division of Project and Resident Programs U. S. Nuclear Regulatory Commission Region 1 - 631 Park Avenue King of Prussia, Pennsylvania 19406 Docket No. 50-293 CAL No. 84-03 Response to Confirmatory Action Letter 84-03

Dear Sir:

This refers to the completed and planned actions taken by this company in re-gards to the incident of January 18, 1984, in which a Health Physics Techni-cian was thought to have exceeded the regulatory limits for quarterly extremity radiation dose. The information herein submitted satisfies the commitments as mutually agreed upon and defined in Confirmatory Action Letter 84-03.

This submittal contains three elements which are:

(1) An item-by-item response to each activity discussed in Confirmatory Action Letter #84-03.

(2) A summary statement regarding the subject issues.

(3) A seven part Expr,sure Evaluation conducted and prepared by our Health Physics Organization.

CAL #84-03 Item No. 1 Prevent access of the individual who may have exceeded the regulatory limits for quarterly extremity radiation dose to radiation areas at Pilgrim until assignment of his personal exposure. Limit subsequent exposure accordingly.

Response

The individual was restricted from radiation areas commencing the afternoon of January 18, 1984. He was inadvertently allowed entry to radiation areas on the morning.of January 20, 1984, due to the misassumption that the ex-

.posure evaluation was completed. The misassumption occurred because the ex-tremity dose estimate figure at that time was one to two rem and, as this was not significant extremity exposure, radiation protection supervision de-termined that the individual could return to work. When this was discovered 8402270271 840215 PDR ADOCK 05000293 G PDR g(,

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sosTON EDISON COMPANY Mr. Richard W. Starostecki Prge on January 20, 1984, the individual was again restricted from radiation areas until the formal exposure evaluation was completed on February 7, 1984. Based on the results of the exposure evaluation and exposure as-signment, subsequent restriction from radiation areas was determined not to be necessary.

CAL Item No. 2 Establish and maintain positive health physics coverage for the work per-formed in the Control Rod Drive (CRD) Repair Room pending completion of the evaluation described in Item 4.

Response

On Thursday, January 19, 1984, the Chief Radiological Engineer ordered the immediate implementation of constant health physics coverage for all entries into the CRD Repair Room. (This did not apply to entries to the "A" RHR Valve Room or the Steam Tunnel which requires an individual traverse, a small section of the CRD Repair Room.) The Sr. Radiological Engineer then instructed the personnel directly responsible for providing health physics coverage on the CRD replacement job of the constant H. P. coverage require-ment. In addition, an entry was made in the CRD Repair Room H. P. Log Book concerning the requirement. Subsequently, all applicable Radiation Work Per-mits were revised to reflect the requirement.

CAL Item No. 3 Evaluate, by January 31, 1984, the actions of all workers who may have en-tered the CRD Repair Room on the 23 ft. elevation of the Reactor Building between January 14 and 10, 1984. Assign resulting personnel exposure by February 15, 1984, and implement personnel exposure restrictions, as neces-sary, to comply with 10 CFR 20. 101.

Response

In order to evaluate the actions of all workers who may have entered the CRD Repair Room between January 14 and January 18, 1984, (inclusive), all RWP

Sign-in Sheets associated with the CRD Repair ' ,cnn were reviewed and all per-sonnel that may have had access to the subject room were identified.

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Sixty eight persons were identified who may have had access. All but two of these persons were interviewed, and their actions associated with the CRD Repair Room were determined and documented by two senior members of the Radi-ological Group's management staff. The two other persons were not interviewed because they had been laid off. Their actions were reviewed with fellow work-ers that accompanied them during the time identified on the RWP Sign-in Sheet.

From this information it was determined that one of the individuals had not actually been in the CRD Repair Roor. between January 14 and January 18, 1984.

The other individual was entering the "A" RHR Valve Room and at no time entered the area of the CRD Repair Room that is in question.

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. BOSTON EOlsON COMPANY

-Mr. Richard W.' Starostecki Pzge' 'The. individual known to ' have handled the chip was interviewed immediately after Radiological Group management personnel were notified of the inci-dent. He was also interviewed by Radiological Group management personnel several times throughout the course of the investigation. Four people who were determined.to be those most likely to have handled the chips or know-ledgeable about anybody possibly handling the chips were initially inter-viewed by January 20, 1984. Three of these individuals were interviewed by.'a Senior Health Physics Technician assigned to the CRD replacement pro-ject. He reported the results of this interview to the Sr. ALARA Engineer.

The fourth individual was interviewed by the Sr. ALARA Engineer. Of the sixty-six people, in total who were interviewed, the majority of the inter-

. views occurred on January 25 and 26, 1984. It should be noted that at no time during the entire interview process was there any indication that an individual. handled the chips other than the individual known to.have handl3d the chips on January- 18, 1984.

Of the sixty-six people interviewed, only five people indicated coming in

. physical contact with the bucket with the chips in it. (This does not in-clude the individuals who " created" the bucket during a control drive dis-assembly on January 14, 1984. All of these individuals used long-handled

-tools and wore extremity dosimetry). .Both the extremity and whole body ex-

.posures were evaluated for these individuals. The results of the evalua-tions indicated that one of the five individuals potentially received a

. maximum of 30 mrem.to the hands. The whole body exposure (as indicated by each individual pocket dosimeter and TLD) was determined to be representa-

.tive of the actual exposure received after evaluation of the geometry be-tween the bucket, the various parts of the whole body and the location of the dosimetry on the body, while the bucket was being handled each time.

As a result.of this evaluation, it has been determined that exposure al-ready assigned by the routine TLD and pocket dosimeter monitoring program was accurate.

L The eveluation of the actions of'all workers was completed by January 27, 1984.

~ CAL Item No. 4.

p Evaluate the health physics controls used for the work in the CRD Repair

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Room between January 14 and 18, 1984. Include in this evaluation, as a mini-mum: (a) the adequacy of the information provided to workers relative to the hazards associated'with the radioactive material in the CRD Repair Room; and (b) the adequacy of. the radiation surveys performed, the radiction work per-mit used, sourcc controls, and the personnel dosimetry supplied to the work-ers involved.

Response to Item No. 4 An evaluation of the health physics controls. used for the work in the CRD Repair Room between January 14 and 18, 1984, was performed. There were three primary components to this evaluation. The first component was an in-

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8DSTON EpisDN COMPANY Mr. Richard W. Starostecki Pcge intensive review by the Radiological Group management staff of the controls that were in place. The second component was interviews with the Health Physics personnel directly responsible to implement the health physics cov-erage for work in the CRD Repair Room during this period. The third compon-ent was interviews with the personnel working in the CRD Repair Room during this period. (The interviews referred to are the same interviews referred to in Response No. 3 above. The questionnaire used for the interviews was structured to elicit information concerning the health physics coverage as well as information concerning the chips and the bucket.) Based on the re-sults of the evaluation, it was determined that the health physics coverage was adequate and that one improvement was desirable. This improvement was the requirement for constant health physics coverage for all work in the CRD Repair Room. This improvement was identified very early in the evaluation and was immediately implemented as described in the Response to Item No. 2 above.

Referring specifically to each of the items listed in CAL Item No. 4, the following is submitted:

a) " adequacy of the information provided to workers relative to the hazards associated with the radioactive material in the CRD Re-pair Room" Based on the interviews with workers, those who worked in the vicinity of the bucket were either aware of the high dose rates from the bucket specifically, or of the dose rates in the room and that they were not to be in that area un-less they had to. (Some workers indicated they were not aware of the bucket or the high dose rates in the vicinity of the bucket. These workers, though, were those whose assignment in the room did not require them to go in that part of the room.) When asked if the H. P. Technician signing them in on the RWP knew of the task they were to perform and the areas of the room to be entered, they replied in the affirmative. Therefore, it has been determined that the infor-mation provided to the workers was adequate except for one instance which we identified. This instance involved the entry to the CRD Repair Room on the morn-ing of January 18, 1984. The individuals were not told about the bucket and its associated dose rates. These individuals did move the bucket and remcve some CRD components from it and were not aware of the associated dose rates.

Several problems were identified that contributed to these individuals not know-ing the dose rates associated with the bucket. First, a survey of the CRD Re-pair Room had been performed on the previous shift which indicated the location of the bucket and the dose rates. All copies of the survey (the survey forms are multi-part) erroneously were placed in the " Supervisor's Review" box in the Health Physics office. One copy should have been placed in the RWP folder. In addition, the Health Physics Technician briefing t'_a three workers prior to their entry had not been informed during shift turnover about the bucket. He did re-view the RWP folder, but the survey from the previous shif t was not present.

The Health Physics Technician did not know about the bucket; therefore, could not inform the three workers of its presence. A lack of adequate communications, both written and verbal, was the cause of this inadequacy in the health physics coverage.

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BOSTON. EDISON COMPANY Mr.' Richard W. Starostecki

'Page A memo has been issued by the Chief Radiological Engineer to all Health Phy-sico personnel stressing the requirement fce complete shift turnovers and preper communications between Health Physics personnel.

.b) "the_ adequacy of radiation surveys performed" An evaluation of 'all of the surveys performed in the CRD Repair Room from

' January _14 to January 18, 1984, was performed. All surveys reviewed indi-cate at least the higher does rates in the vicinity of the bucket and most

' surveys specifically indicated the presence of the bucket and its associated

-dose rates. Based on the results of this evaluation, the radiation surveys performed in the room during this period were determined to be adequate.

c) "the radiation werk permit used" An evaluation of the Radiation Work Permit (RWP) used as uell as all RWP's covering work in the CRD Repair Room was performed. Based on this evalua-tion it was determined that the RWP's and the requirements they imposed were adequate and that one improvement should be implemented. This improve-ment is the requirement for constant health physics coverage as described in the Response to Item No. 2 above.

.d) " source control"

An evaluation of the source controls being implemented in the CRD Repair Room

- was performed. Based on the results of this evaluation, it was determined that the source control was adequate and that improved source control would also be achieved by the required constant health physics coverage as described in the Response to Item No. 2 above. This evaluation did identify one instance

.of inadequate source control during the entry to the CRD Repair Room by three individuals on the' morning of January 18, 1984. The cause for this instance is provided in the response to Section "b" above as it is directly related to the

-inadequate briefing to the workers. The memo referred to in Section "b" and the required constant health physics coverage will prevent the recurrence of this event, e) "the personnel dosimety supplied to the workers involved" An evaluation of the personnel dosimety supplied to the workers involved was performed. This evaluation also included personnel dosimetry supplied to all workers at PNPS.

This evaluation involved the review, in particular, of the use of both ex-tremity dosimetry and the use of whole body dosimetry. Specific extremity monitoring 'at PNPS is normally accomplished by securing a regular TLD to

.the extremity to be monitored. (A self-reading dosimetry is also normally secured to the same area). In particular, when the extremity to be moni-tored is the hand, the TLD is secured to the wrist. If the surface dose rates are such.that a portion of the hand is likely to receive a signifi-cantly higher does than the wrist, long-handled tools are employed so that

'the does rates to all parts of the hand are essentially the same. Similar techniques are utilized when necessary for each of the extremities. Whole

-body monitoring at PNPS is normally accomplished by wearing a TLD badge and

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BOSTON EDISON COMPANY

Mr. Richard W. Starostecki Page self-reading dosimeter on the front of the trunk of the body, usually the waist or chest area. However, when a specific situation involves a poten-tial for a portion of the whole body to receive a significantly higher dose than that to the area where the badge is normally worn, either the TLD badge and self-reading dosimeter are worn at the area of expected highest dose or TLD badges and dosimeters are worn at more than one area of the whole body and the individual's dose is assigned after analysis of all of the TLD badge results.

Based on the results of this evaluation, it was determined that personnel

. dosimetry supplied to workers in the specific incident being discussed and to all radiation workers at PNPS is adequate and reflects the state of the art of personnel dosimetry.

Summary The results of the investigation performed subsequent to this incident in-dicated that (1) there was an error in judgement in which a trained and qualified individual improperly handled highly radioactive material (2) there were several breakdowns in communication including a sole reliance on log books to transmit data which more appropriately should have also been reflected in the appropriate RWP's and (3) there is the need to reemphasize, to all Health Physics personnel, the unique radiological hazards associated with physically small, high dose rate sources due to the inaccuracies as-sociated with " contact" dose rates as measured by conventional survey in-struments.

One potential problem resulted from inadequate communications between health physics personnel; however, adequate communications would not have prevented

.this incident. The communications problem has since been corrected. The in-dividual in an interview following the occurrence, was questioned as to what he would have prescribed if someone had wanted to remove an unknown source from a bucket and he properly stated the requirements which he would impose.

This incident is analogous to an experienced electrician touching an energized wire because he neglected to check it properly first, or an experienced car-penter cutting c2f a thumb or finger while operating a saw, or an experienced mechanic losing a finger or hand because he put them into operating equipment.

'In.these cases, the people are adequately trained and experienced personnel but still, for' inexplicably intangible reasons, they neglect or forget their training and exper. fence and make a serious judgemental error which may-lead to actual bodily injury. In all examples, which have occurred many times, in-dividuals failed.to take a known precautionary step they have taken many times previously. Finding a solution to totally prevent these types of situations

.ougr not be possible.

We trust this submittal will meet with your approval and we are prepared to meet and further discuss this incident, our subsequent restorative actions or any'other aspect involved to facilitate your review.

Respectfully submitted, W. D. Harrington Attachment (s)

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• EXPOSURE EVALUATION OF INCIDENT OF JANUARY 18, 1984 i

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, I. Overview of Incident i.

II. Quantification of Sources -

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III. Geometry of Event IV. Time of Exposure

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I V. Relevant-Information from Personnel Interview

-t VI. Estimate of Exposure - Gamma .

VII. Estimate of Exposure - Beta S

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I I. OVERVIEW OF INCIDENT i

. On January 18, 1984 a Health Physics Technician identified a white i plastic bucket in the CRD Repair Room with a notably high dose rate on a contact with the outside of the bucket. The rerorted measured contact I

g dose rate on the surface of the bucket was 10E/hr.

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{ In an attempt to reduce exposures to personnel working in the room C T

i the HP Tech decided to identify, segregate and transfer the source (s) of i these radiation levels to a lead pig.

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t The technician removed the suspected sources of radiation, several small metal chips, from the bucket by hand, surveyed each, and placed e

them in the lead pig. During this transfer dose rates well in excess of i the original measurement of 10R/hr were observed when individual metal t

j chips were held essentially in contact with the survey instrument.

f Due to the fact that dose rates appeared to increase greatly as the

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i distance from the source to survey instrument decreased it appeared that ,

true contact dose rates to the individual's fingers might be greatly in excess of the survey instrument reading. Therefcre an investigation was

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.; instituted to determine the true contact dose rates, exposure times and J

resulting extremity exposure.

The results of this investigation indicate with certainty the individual in question received no more than 4.56 Rem gamma dose and negligible beta exposure resulting from contact with the sources identified as having been handled. Indeed, all the sources presen" in the lead pig if handled simul-taneously, could not have resulted in a gamma exposure greater than 10.41 Rem.

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The appropriate extremity exposure to assign for this incident is

! 4.56 Rem gamma with negligible beta contribution due to the thickness of the gloves worn during the incident.

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[ II. QUANTIFICATION OF SOURCES I In an effort to accurately determine the contact dose rates several 7 tests were performed. First the radioactive chips were retrieved from the. lead pig and individually placed in true contact with a TLD chip, i

The time of exposure was carefully measured and the location of the mutual r.

chip relative to the TLD chip was carefully maintained. The source chip and receptor chip were truly in contact except that two intervening layers of plastic and one layer of cotton were used to simulate the technician's gloves.

Each source chip was exposed to three different TLD chips for known time

. periods (except for chip #7 which was exposed only twice). Exposure times were all greater than 5 minutes _thereby minimizing errors in time measurement.

Each.TLD was read out in a conventional manner.

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The raw results of these measurements are contained on attachment A and the corrected (background subtracted) and averaged results are contained on

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attachment B.

In addition, to assess any beta dose contribution and to verify the energy of the gamma radiation a Ge-Li an'alysis of a fraction of one of the source chips was also performed. The results are presented on attachment C. These results confirm the assumption that Co-60 comprises essentially all of the

l e activity contributing to tha cxposurs. Tha rssults cleo c;rva to identify the maximum beta energy present as 0.314 Mev. which has a smaller range than required to penetrate the 95 mg/cm2 thickness of the gloves and dead skin layer (see attachment D).

Although the HP Technician remembered handling only 3 to 5 separate chips during three different transfer movements, 8 chips were found in the shielded container. 'Ib ensure a thorough evaluation, dose rate measurements were made ,

on all 8 chips (the two smallest chips were taken together as one).

I III. GEOMETRY OF EXPOSURE t

This exposure event was unusual in that the sources of radiation were of unusually small dimensions as shown in attachment E. These dimensions are small when compared with the size of the probe or sensitive volume of conven-tional survey instruments.

As a result, dose rates considered to be " contact" as measured by a survey instrument, underestimated the true contact dose rate by a factor of from 20 to 55 with 55 being the case for the smallest source chip (see attachment F).

To obtain accurate contact dose rate measurements a detection device with dimensions comparable to the source and with no intervening casing or housing I

was placed in true contact with the source chip. This device was a personnel dosimeter chip, 1/8" x 1/8" X .035". This arrangement closely approximated the true source-receptor geometry during the exposure period. Two layers of rubber and one of cotton representing the protective clothing worn by the individual were the only material intervening between the source and receptor. Continuous pressure was applied during the measurement to ensure source-receptor contact.

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IV. TIME OF EXPOSURE r Due to the unusually high dose rates an accurate estimate of the exposure I time was vital in assessing dose. The individual who actually handled the radioactive chins participated in a time-motion study performed under accu-

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rately simulated and controlled conditions. The individual wore a respirator and 3 pairs of gloves during this study and recreated the physical arrange-f.

. ment of pertinent objects (source bucket, extender survey instrument and lead c pig) as accurately as possible. The individual repeated his physical motions l

during the period in question ten times during this simulation. Each series

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of motions involved the movement of three simulated source chips from the source bucket, to the survey instrument and into the lead pig. The results of this time-motion study are presented in attachment G. The average total time of contact exposure to the source chips was 8.02 seconds.

k' V. RELEVANT INFORMATION FROM PERSONNEL INTERVIEW The Health Physics technician involved in the exposure was interviewed on several occasions. He was able to identify from pictures with considerable confidence, those chips he had handled on the day of the incident. He iden-

-tified the chip moved on the first motion as either chip #3 or #7 (both chips have similar shapes), on the second motion as either chip #2 or #4 (also similar in shape) and on the third motion,as chip #5 (actually two small chips).

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He was also quite sure of the physical locations of the source bucket, survey instrument and lead pig since he had pre-planned the activity to limit exposure.

He was also confident about the path and duration of his motions.

Although he had originally reported dose rates as high as 300r/hr on a chip (s) as measured by his survey instrument, he admitted that he had not allowed the meter to stabilize at any specific reading but that he had ob-

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/ served the meter needlo "hesding tcwird 300R", at which time ha threw the source chip (s) into the lead pig.

The technician stated that he had no reason to believe that the lead pig was empty when he started putting chips into it. Therefore some chips must have been present in the pig from some prior activities.

. VI . -ESTIMATE OF EXPOSURE - GAMMA q The final exposure estimate considers the highest credible contact dose rates, the time of contact exposure and number of chips moved. Since the technician was able to identify the chip moved on the first motion as pos-sibly being either of two chips, the chip with the highest dose rate was considered. The same situation occurred for the second motion. The chips i moved on the third motion were positively identified as the two smallest

of the group.

i Gamma contact dose rates on each chip moved (the last two small chips are considered as one) were multiplied by the time of contact (less than 3 seconds on each move) and added, to obtain the total contact exposure as follows:

0.505R/sec X 3 sec. = 1.52 R 0.783R/sec X 3 sec. = 2.35 R 0.230R/sec X 3 sec. = 0.69 R (

TOTAL = 4.56 R Indeed, even if the individual involved had handled all of the pieces found .a the lead pig (which is unlikely if not incredible) he would have received no more than 10.41 Rem to the extremity from Ganma radiation.

VII. ESTIMATE OF EXPOSURE - BETA

The thickness of the rubber and cotton gloves together (.88 mg/cm 2) along with the thickness of the dead skin layer (7 mg/cm2 ) limited beta exposure to insignificant values.

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ATTACHMENT A RAW EXPOSURE DATA MREM Hot Chip # Time-On Time-Off TLD # Net Time i

171880 1 10:50 10:56 218651 5'-01" I 146730 1 10:57 11:02 218503 5'-01" 135510 1 11:03 11:08 217248 5'-01" 240350 2 11:09 11:14 218690 5'-01" 237040 2 11:14 11:20 102689 5'-02" 230770 2 11:21 11:25 218866 5'-01" <

151330 3 11:26 11:31 027799 5'-13" 157900 3 11:32 11:37 028015 5'-01" 152760 3 11:37 11:42 099349 5'-00" 204800 4 11:42 11:47 218581 5'-01" 205290 4 11:47 11:52 114145 5'-01" 200350 4 11:53- 11:58 099398 5'-01" 5 11:59 12:04 218260 5'-02" Nota (1) 76060 64573 5 12:04 12:09 217144 5'-01" 67350 5 12:10 12:15 114428 5'-00" 121690 6 12:15 12:20 103317 5'-01" 122080 6 12:20 12:25 102979 5'-01" 120950 6 12:26 12:31 026693 5'-01" 118020 7 12:32 12:37 113670 5'-01" 103190 7 12:38 12:43 217744 5'-01" (1) Two slivers considered as 1 chip.

(2) . Control TLD #114262 read 30 mrem. ,

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. CORRECTED EXPOSURE DATA 4

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Chip # TLD # l'et Dose ' Net Time Dnse Rate

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l 1 218651 171.850 301 0,571

. 1 218503 146.700 301 0.487 1 217248 135.480 301 0.450

'I Average 0.503 Rem /sec c (1911 Rem /hr) f-l 1

2 218690 240.320 301 0.798 1 2 102689 237.010 302 0.785 l t 230.740 301 0,767 2 218866 Average .783 Rem /sec (2819 Rem /hr)

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3 027799 151.300 313 0.483 9 3 028015 157.870 301 0.524 9 3' 099349 152.730 300 0.509 Average 0.483 Rem /sec (1818 Rem /hr)

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-4 218581 204.770 301 0.680 4~ 114145 205.260 301 0.682

i. 4 099398 200.320 301 0.666 i

i Average 0.676 Rem /sec (2434 Rem /hr) (

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5 5 218260 76.030 302 0.252 5 217144 64.543 301 0.214

.s 5 114428 67.320 300 0.224 l~

Average 0.230 Rem /sec (828 Rem /hr)

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- ATTACIDENT 2

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. CORRECTED EXPOSURE DATA - Page 2

--Chip #' TLD # Net Dose Nat Time Dose Rate

_ (Rem) (Sec) (Rem /Sec) 4 6 103317 121.660 301 0.4 04

'6 102979 122.050 301 0.405

.' 0.402

> 6 026693 120.920 301 Average 0.404 Rem /sec l C h (1454 Rem /hr) i i

.i- 7 113670 118.000 301 0.392

7- 217744 103.160 301 0.343 I t i

4 Average 0.368 Rem /sec (1325 Rem /hr)

TCffAL OF AVERAGE VALUES OF REM /SEC = 3.4,69 Rem /sec i

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. , -  ; DECAY TIME (MIN): 1 ATTACHMENT C CALIB CURVE 4.. 8 3

,q' l DILUTION FACTOR.! 1 5

Go-Li Analysis of a Chip ~)

DEAD TIME (%)...!

(p (+-KEV =1.5, 4SIG=1.5, 4SM00THS=1) r)

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SAMPLE DESCRIPTION..: CRD SLIVER  !

() CCSRP,.0PERATOR......! MITCHELL () i DATE 1 HOUR SAMPLED.:

DATE 1 HOUR ANALYZED: 1-26-84,1418 j COUNT (YES/NG) ?Y SET I/O DEVICE TO REMOTE, PRESET TIME TO O O

() COLLECT TIME (SEC) ? 1000 c)

. NOW COUNTING e c COUNT DONE 6 7 GAMMA SPECTR0 GRAPHIC ANALYSIS q,

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ENERGY (KEV) ISOTOPES g[ CHANNEL NET AREA (CDUNTS) g) i (g 1055,17 321. 488.19 e) 1445.53 399. 667.21 I-132 1662.66 368. 766.76 NB-95

() . 1714.51 375. 790.52 NB-98,KR-88,MN-54

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1809.65 3767. 834.14  !

1876.19 411. 864.64 CO-58  ;

gg 2165.33 412. 997.14 ()

2548.06 72521. 1172.48 CO-60 2895.64 62839. 1331.67 CD-60 3498.83 57. 1607.80 g) '

(3 3821.87 65. 1755.62 LA-142 C2 C) i RADIONUCLIDE ANALYSIS COLLECT TIME (SEC)..! 1000 ()

(3 ISOTOPE ACTIVITY +- - 2 SIG

-MP- 5 1.52737C ^2 'JC/SAMPL +- 1.17702E-03 ( 77 04 %) 3 MN-54 3, "7 1.69374E-02 UC/SAMPL 1- 1.48626E-03 ( 8.77 %)

gg CO-60 yg, 4.44102E-01 UC/SAMPL +- ~ 3.49146E-03 ( 0.79 %)

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DIFFERENCE g) ISOTOPF THEORETICAL MEASURED ()

NB-95 765.79 766.76 0.97 gj MN-54 834.83 834.14 -0.69 (j CO-60 1332.49 1331.67 -0.82 i STANDARD DEVIATION = 0.83

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. ATTACHMENT D ANALYSIS OF THICKNESS OF PROTECTIVE GLOVES t-4 Rubber Swatch (16 in2 . 103.23 cm2 ).

4003.60 mg = 38.78 mg/cm2 2

it 103.23 cm

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I Cotton Swatch (13.75 in2 - 88.71 cm2 )

1: 888.60 mg = 10.02 mg/cm2

, j' 88.71 cm2 Y

t 7 mg/c.m 2

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Thickness of Dead Skin Layer =

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-I Net' thickness of protective layer = 38.78 X 2 + 10.02 + 7 = 94.58 mg/cm 2

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ATTACHMENT E i

• APPROXIMATE AREAS AND VOLUMES OF CHIPS L6 .

' Chip # Iangth Width Thickness Area volume i

3 1 1 3/8 3/8 1/16" 1.125 in2 .0322 in

. 2 3/4 1/2 1/16 0.875 .0234 C

3' 1 7/8 1/4 1/16 1.000 .0293 4 1 3/8 1/16 0.844 .0234 5* 3/8 3/8 1/1ti 0.375 .0088

}

i-

• 6 1 3/8 1/4 1/16 0.750 .0215 7 1 3/8 1/4 1/16 0.750 .0215

• Totals for two chips t

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ATTACHMENT F

- l

- MEASURED GAMMA DOSE RATES 4

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1 _2 3 4 e

Contact Dose Contact Dose i

. Rate with Rate with TLD Ratio Extender - R/hr R/hr Chip # 3/2 l t <

I T

l -1 90 1811 20.1 t

I

, 2 110 2819 25.6

-F. l 3 ~75 1818 24.2 i

,I 4 100 2434 24.3 I 5* 15 828 55.2 Smallest Chip l

, 6 70 1454 20.8 7 50 1325 26.5 r

5

! h:

!i t

I-

• Actually the two smallest chips taken together.

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- , ----.--,c,,, . ,--vc , - - , - , - , - - - , , - - - -

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

.(.-.-~.

s.

s:

r.

' ATTACHMENT G

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i 9'

RESULTS OF TIME-MOTION STUDY 2 pairs of Rubber Gloves January 25, 1984: 3:15 - 3:45 approx.

1 1 pair of Cotton Gloves Face Mask Net Sec. for

-Run # 3 Kaves

[

, 1 7.77 2 7.37 3 8.33 4 8.05

. ,i 5 7.69 l- 6 8.08 7 8.46 Jk- 8 7.97 9

'l. 9 8.33 ,

l

! 10 8.17

}

t-x = 8.022'sec. S = .355 sec.

t i Min = 7.37 Max = 8.46 ol,.

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