Information Notice 1987-39, Control of Particle Contamination at Nuclear Power Plants: Difference between revisions
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| issue date = 08/21/1987 | | issue date = 08/21/1987 | ||
| title = Control of Particle Contamination at Nuclear Power Plants | | title = Control of Particle Contamination at Nuclear Power Plants | ||
| author name = Rossi C | | author name = Rossi C | ||
| author affiliation = NRC/NRR | | author affiliation = NRC/NRR | ||
| addressee name = | | addressee name = | ||
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| page count = 15 | | page count = 15 | ||
}} | }} | ||
{{#Wiki_filter:..-.i | {{#Wiki_filter:! . . - . i | ||
V' 'SINS No.: 6835 iN 87-39 UNITED STATES | |||
NUCLEAR REGULATORY COMMISSION | |||
NOTICE NQ. 87-39: CONTROL OF HOT PARTICLE CONTAMINATION | OFFICE OF NUCLEAR REACTOR REGULATION | ||
WASHINGTON, D.C. 20555 August 21, 1987 NRC INFORMATION NOTICE NQ. 87-39: CONTROL OF HOT PARTICLE CONTAMINATION | |||
AT NUCLEAR POWER PLANTS | AT NUCLEAR POWER PLANTS | ||
Line 27: | Line 28: | ||
==Addressees== | ==Addressees== | ||
: | : | ||
storage facilities holding | |||
and spent fuel | All nuclear power reactor facilities and spent fuel | ||
an NRC license or a construction permit. | |||
Background and | |||
and | |||
==Purpose== | ==Purpose== | ||
: IE Information | : | ||
information on events in- IE Information Notice 86-23 (Reference 1) provided skin contamination by small, volving excessive skin exposures resulting from activity (hot particles). Since | |||
Notice 86-23 (Reference | |||
1) provided | |||
skin exposures | |||
resulting | |||
from | |||
Since | |||
of | highly radioactive particles with high specific been more of these events, and a | ||
that information notice was issued, there have Operations (INPO) (Reference 2) | |||
recent report by the Institute of Nuclear Power This information notice pro- provides additional information on this subject. and discusses degraded fuel | |||
vides information on some of the subsequent eventsfuel reconstitution as major | |||
and a lack of proper radiological control during learned also are included. | |||
sources of hot particles. Generic licensee lessons | |||
information for applicability | |||
It is expected that recipients will review this to preclude a similar | |||
to their facilities and consider action, if appropriate, suggestions contained in this | |||
problem occurring at their facilities. However, no specific action or | |||
notice do not constitute NRC requirements; therefore, written response is required. | |||
Discussion: | |||
hot particle exposures were | |||
During the first 6 months of 1987, events involving Two events in late 1986 (at | |||
reported at nine different nuclear power stations. exceeding NRC regula- V.C. Summer and San Onofre) involved exposures apparentlyof eight of these | |||
tory limits. Attachment 1 provides summary descriptions from the referenced inspec- events. More detailed descriptions can be obtained Reports are available | |||
tion reports for each event. (Copies of NRC Inspection Washington, D.C.) | |||
from the NRC Public Document Room, 1717 H Street N.W., | |||
degraded fuel and neutron- Hot particles come primarily from two major sources: While much of the | |||
activated corrosion and wear products (e.g., Stellite). corrosion | |||
information in this notice is pertinent to both neutron-activated | |||
as activated particles) and | |||
and wear product particles (hereafter referred to | |||
K> QIN 87-39 August 21, 1987 irradiated fuel particles (hereafter referred | |||
to as fuel particles), a major | |||
concern of this notice is extended facility operation | |||
particle | the resulting problems with fuel particle contamination. with degraded fuel and | ||
NRC review of licensees' corrective actions, discussions On the basis of an | |||
operating staffs, and information obtained by with licensees' | |||
NRC inspectors, the lessons | |||
learned and licensee good practices resulting | |||
from the events summarized in | |||
Attachment 1 are as follows: | |||
1. Extended power plant operation with degraded fuel | |||
result in widespread dispersal of fuel particles. (leaking fuel pins) can | |||
experience fuel particle contamination problems Some plants continue to | |||
have | pins have been removed because of the residual long after leaking fuel | ||
systems. Some plants with these problems have contamination of plant | |||
for | for missing fuel pellets and fragments and to started programs to account | ||
identify measures to recover | |||
this material. | |||
2. Considerations concerning the handling of leaking | |||
following: fuel include the | |||
a. Special techniques and precautions for handling | |||
are necessary to prevent aggravating the spread leaking fuel bundles | |||
For example, containment devices should be used of fuel particles. | |||
fuel. The lack of proper radiological controls when reconstituting | |||
fuel reconstitution process in the San Onofre and oversight of the | |||
3 fuel pool led to loss | |||
of control and dispersal of numerous fuel particles | |||
Fuel particles then spread through the plant spent into the pool. | |||
to the liquid radwaste systems. fuel systems and | |||
b. A damaged, leaking fuel pin that is not properly | |||
segregated from the common fuel pool area could contained and | |||
long-term source of fuel particle contamination. be a significant, c. Plants should be aware that NSSS vendors' special | |||
refueling tools and | |||
contamination | equipment could be a source of fuel particle contamination. | ||
tools and equipment should be carefully surveyed These | |||
and before they are shipped to other facilities. before they are used | |||
3. Some plants that have operated for extended periods | |||
of | fuel and plants with activated particle problems of time with degraded | ||
specialized, comprehensive training programs for now have instituted | |||
workers and general employees. These programs plant system maintenance | |||
inform and prepare the plant staff to cope with are designed to better | |||
of | particle problems. Additionally, as part of the continuing fuel | ||
comprehensive | |||
control programs, special new procedures to improve contamination | |||
surveys for detection | |||
: -- | |||
. .IN 87-39 August 21, 1987 of.hot particles have been prepared and health physics technicians have | |||
been trained in their use. Decontamination and dose evaluation methods | |||
and procedures that focus on hot particles have been implemented. (See | |||
summaries of events at Trojan and.San Onofre in Attachment 1.) | |||
.4.. In general, ;licensees have upgraded their programs for contamination | |||
monitoring of "clean," laundered anti-contamination protective clothing | |||
(PC). However, PC continues to be a means of transferring both fuel | |||
particles and activated particles. Some facilities need to consider | |||
making their PC monitoring programs more sensitive. For example, some | |||
to | licensees that are using contractor laundry services found the contrac- tor's alarm on the radiation monitor (used to screen PC) too high to | ||
-detect 0.4 microcurie (VCi) particles. Moreover, when commercial plant laundry | |||
services are used, it is possible that PC from a "particle-free" | |||
* *-can be mixed with PC from a plant with hot particle problems. Finally, at.leastrone licensee was relying solely on monitoring of large bundles | |||
of washed PC (bulk surveys) and was not monitoring samples of individual | |||
PC. For plants with identified particle problems, individual PC items | |||
may have to be checked before they are reused after cleaning. | |||
5. Except for the-Trojan event discussed in Attachment 1, to date, no | |||
licensee has reported detecting hot.particles during airborne sampling. | |||
However, as a precaution,,some licensees have elected to provide workers | |||
with respiratory protection for performing maintenance on plant systems | |||
known to-be a source of hot particles. No plant has reported inhalation | |||
or ingestion of hot particles by any worker. | |||
6. Hot particles in contact with skin.produce very high dose rates. Diligent | |||
personnel contamination surveys performed as soon as practical after . | |||
completing work involving contamination are needed to minimize potential | |||
exposure times.- | |||
7. Approximately 75 percent of the U.S. power reactor facilities are cur- rently using new high-sensitivity whole-body contamination monitors. | |||
These state-of-the-art contamination monitors increase the probability of | |||
detecting hot-particles on plant personnel while reducing the likelihood | |||
of inadvertently releasing particles from the plant site. To-date, most | |||
of-the particles found on personnel have:been detected by these new | |||
monitors. Even with use of the new monitors, a few instances have oc- curred where hot particles have inadvertently been carried home by workers | |||
and | . and have-been detected in the home or on the worker returning to the site. | ||
No significant ,public exposures have been reported to date. | |||
8. In a recent study for the NRC (Reference 3), it was reported that a plant | |||
operating with 0.125 percent pin-hole fuel cladding defects showed a | |||
general five-fold increase in whole-body radiation exposure rates in some | |||
IN 87-39 . | |||
August 21, 1987 areas of the plant when compared to a sister plant with | |||
fuel (<0.01percent leakers). Around certain plant systems high-integrity | |||
fuel may elevate.-radiation exposure rates even more. the degraded | |||
- | |||
9. Maintenance-on valves with Stellite components can cause | |||
cobalt-containing debris with Co-60 as the resultant introduction of | |||
product. Some plants have instituted work controls (e.g.,neutron activation | |||
ment and post-maintenance cleaning) to minimize this input use of contain- systems (Reference 4). into reactor | |||
Health Implications and Radiation Protection Criteria | |||
for Hot Particle- Exposures of Skin: - | |||
A hot'particle on the skin gives a high beta dose to | |||
a small area.' Any radia- tion dose to the skin is-assumed to result in'some increased | |||
cancer, although'this type of cancer is rarely fatal.' risk of skin | |||
of the skin | indicate that highly localized irradiation of-the skin'by Experiments with animals | ||
likely to'cause skin cancer than more uniform irradiation hot particles is less | |||
of radioactive material.:- by the same quantity | |||
In addition to any increased risk of cancer, large | |||
particles also may produce observable effects such doses to the skin from hot | |||
as reddening, hardening, peeling, or ulceration of the skin-immediately around | |||
effects appear only'after a-threshold dose is exceeded.the particle; These | |||
the 'skin | particles 'equired to-produce these effects'in the 'skin The doses from hot | ||
cisely;-Ihowever, -it appears likely, except for a point are'not known pre- effects will only be seen for doses of hundreds of rems reddening,-that these | |||
effects have been seen to date on any workers who have or more.'- No such | |||
particles, even though one exposure has been measured been exposed to-hot | |||
512 rem. or calculated as high as | |||
Recent reviews of radiobiology and radiation protection | |||
of hot particle exposures, have been provided-by-Wells | cluding considerations of hot particle exposures, have criteria for skin, in- been provided-by-Wells | ||
5) and Charles (References | (Reference 5) and Charles (References 6 and 7). '' | ||
The NRC staff recognizes the need for more'information | |||
radiation on skin and particularly the effects-of hot on the effects of | |||
the | The staff has requested the National Council on Radiation particle irradiation. | ||
Measurements (NCRP) to. study the health significance of Protection and | |||
on | and to provisde recommendations- based on the findings of hot particle exposures | ||
recommendations may result in changes in NRC requirements this study. These | |||
particle exposures. However, until these requirements with respect to hot | |||
are changed, IE Infor- mation Notice 86-23 (Reference 1) contains current information | |||
evaluating doses to skin resulting from hot particles. for use in | |||
./ .. IN 87-39 August. 21, 1987 Page 5 of S | |||
oI specific action or.written response is required by this information notice. | |||
* you have any questions about this matter, please contact the Regional | |||
Admiistrator 'f the appropriate regional office or this office. | |||
e, | |||
.harles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technwcal | Technwcal Contact:- James E..Wigginton, NRR | ||
(301) 492-4663 John D. Buchanan, NRR | |||
.(301) 492-7293 References | |||
Notice 86-23, "Excessive | I. JAE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tihn With Hot Particles," April 9, 1986. | ||
2i. nstitute of Nuclear Power Operations, Significant Event Report 18-87 (Rev..2), "Radiation Exposure From Small Particles," July 16, 1987. | |||
3,- Hoeller; M. P., :G. F. Martin, and D. L..Haggard, "The Impact of Fuel | |||
*-Cladding Failure Events on Occupational Radiation Exposures at Nuclear | |||
:PowerPants. Case Study: PWR During RoutineOperations," NUREG/CR-4485 (PNL-5606), January 1986. | |||
Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From | |||
H4 | |||
.`Valve IMaintenance," Electric Power Research Institute, EPRI NP-3220, Final | |||
::Report, August 1983. . | |||
5.. Welli, 3., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a | |||
: | |||
. Workshop. heldat Saclay, France, on October 9-11, 1985, Brit. | |||
heldat Saclay, France, on October 9-11, 1985, Brit. | |||
.J3. Radiology, Supplement No. 19, pp. 146-150 (1986). | |||
Radiation | * .6. Charles, 4.W., "The Biological Bases of Radiation Protection Criteria for | ||
Exposure," in "Dosimetry | Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta | ||
of | Particles and Low Energy X-Rays," Proceedings of a Workshop held at | ||
Sacay, Francei October 7-9,-1985," Radiation Protection Dosimetry 14 (No. | |||
- | |||
79-90 (1986). | |||
P2),pp. | |||
-7. Charles, 14. W., "Skin, Eye, and Testis: Current Exposure Problems and Recent | |||
. .Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. 69-81 (1986). | |||
Attachments;.. .. | |||
. | -l.*. EventSummaries | ||
.2.. List-4f Recently Issued NRC Information | .2.. List-4f Recently Issued NRC Information Notices | ||
Attachment 1 IN 87-39 August 21, 1987 EVENT SUMMARIES | |||
San Onofre 3. Events Durina November 1986 - March 1987, Inspection Report | |||
No. 50-362/86-37 Background: | |||
At the onset of the first fuel cycle, significant fuel degradation was evident. | |||
The plant continued to operate with approximately 105 defective fuel pins. In | |||
fuel | late 1985 during the first refueling outage, a fuel pin was inadvertently | ||
pulled apart during the fuel reconstitution process. Several fuel pellets fell | |||
and dispersed throughout the fuel pool. Fuel particles had previously been | |||
detected early on during reconstitution on fuel handling tools and on the | |||
fuel pins | refueling floors. All the severely damaged fuel pins were then grouped into | ||
one fuel bundle and stored in the pool without any containment. | |||
Event Specifics: | Event Specifics: | ||
From January 2 through February 20, 1987, the licensee's | From January 2 through February 20, 1987, the licensee's aggressive hot parti- cle inventory and tracking system indicated that 92 "new" fuel particles | ||
aggressive | |||
hot parti-cle inventory | |||
and tracking system indicated | |||
(recently neutron irradiated), 155 "old" fuel particles, 51 ruthenium, 84 crud, and 42 cobalt particles had been found and analyzed. Before 1987, no formal | |||
tracking program existed. | |||
Several incidents involving hot particles have occurred, including an apparent | |||
worker extremity exposure (hand) of 512 rem during November 1986. As a result, appropriate NRC enforcement actions are currently underway. Three events | |||
involving | involving the inadvertent release of hot particles from the plant site occurred | ||
in February 1987. In two of these events, the radiation dose to the public was | |||
determined to be negligible. However, the third event involved a 0.2.;Ci | |||
particle found by a worker at his home during a self-initiated radiological | |||
survey. The licensee has not yet estimated the potential dose to the worker's | |||
family as a result of this occurrence. | |||
In the licensee's licensee event report (LER No. 86-015, Revision 1) of Febru- ary 22, 1987, the following program improvements for detecting hot particles | |||
and controlling personnel exposures from hot particles were described: | |||
f | |||
Extensive, mandatory use of exceedingly sensitive fixed instrumentation | |||
the | (frisking booths) for the detection of personnel contamination; | ||
Special training (including hands-on laboratory exercises) in radioactive | |||
particle characteristics and survey techniques for all Health Physics | |||
Technicians; | |||
C-. | |||
Attachment 1 IN 87-39 August 21, 1987 Oral and written indoctrination of all managers, first line super- visors and workers in the special problems associated with radio- active particles, including the methods each person must employ to | |||
to | protect himself; | ||
Special procedures to assure detection and control of radioactive | |||
particles which feature the establishment of a clearly identifiable | |||
zone, to demark and contain such particles, surrounded by clearly | |||
identified buffer zones (or solid physical barriers) which are | |||
surveyed frequently to verify that control is being maintained; | |||
Maintenance and wide publication of a radioactive particle census | |||
during outages to maintain station awareness; | |||
The establishment of a Task Force to recommend and implement action to | |||
minimize the future production and movement of radioactive particles. | |||
Trojan, April, 1987, Inspection Report No. 50-344/87-15 Background: | |||
The facility has operated since July 1982 with an estimated 112 fuel pellets | |||
unaccounted for throughout the reactor and support plant systems. The licensee | |||
recovered or located about 264 pellets of the estimated 376 missing after the | |||
1982 refueling outage, which occurred because of the baffle jetting problems of | |||
the 1981 fuel cycle. (See IE Information Notice 82-27, "Fuel Rod Degradation | |||
Resulting From Baffle.Water-Jet Impingement," August .5, 1982.) | |||
Event Specifics: | |||
Shortly after the start of the 1987 refueling outage in April, a significant | |||
increase in personnel skin contaminations occurred. On April 9, high surface | |||
contamination (up to 300,000 dpm/100 cm2) and high airborne activity levels | |||
-.(2E-7 pCi/cc, mixed fission products) in containment resulted from the dis- persal of fuel fragments during reactor vessel. stud removal and stud-hole | |||
plugging operations. The workers in the reactor cavity were wearing respira- tors and no excessive uptakes of.radioactive materials were detected during | |||
followup whole-body counting. Because of the spread of contamination to the | |||
spent fuel building, the licensee stopped all- reactor building cavity work and | |||
all personnel evacuated the area that afternoon. | |||
On April 10, a licensee radiation survey located a hot spot on the cavity floor | |||
near a reactor vessel stud-hole (>100 rad/hr beta and 30 R/hr gamma contact | |||
reading using a portable ion-chamber survey.instrument). On April 11, another | |||
worker located what appeared to be about one-half of a fuel pellet in the | |||
flange area at the stud hole. This partial fuel pellet was removed on | |||
April 12. | |||
Attachment | Attachment 1 IN 87-39 August 21, 1987 On April 17, a radiation protection technician, after performing a survey of | ||
the lower refueling cavity, discovered a fuel particle lodged in his protective | |||
of | rubber shoe cover. This particle was later determined to be composed of | ||
with | approximately 50 mCi of mixed fission product activity; showed readings of 1200 | ||
mR/hr with the window open and 250 mR/hr with the window closed. After a | |||
the | careful time-and-motion study of the technician's activities, the licensee | ||
to | determined that no NRC regulatory dose limits were exceeded. (Licensee esti- mates were 1.2 rem to whole body; 4.6 rem to skin; 9.6 rem to extremities.) | ||
In general, it appears that the licensee experienced a programmatic breakdown | |||
that resulted in several workers receiving significant, unnecessary radiation | |||
exposures from fuel particle contamination. In LER No. 87-08'dated May 8, 1987, the licensee identified the following additional concerns and'corrective | |||
actions. The LER stated in part: | |||
Workers entering containment on April 9 were not-aware of the fuel | |||
particle hazards. As a corrective measure, all personnel with | |||
access to radiological control areas were retrained to be informed of | |||
the fuel particle problem and perform hands-on training to demonstrate | |||
competence in anti-contamination clothing use. Daily reports | |||
to | are being provided to workers on the status of containment activities. | ||
and | Radiation surveys and record keeping were inadequate. As a corrective | ||
measure, new procedures were developed to specifically address | |||
discrete radioactive particles. All radiation protection technicians | |||
particles. | |||
All radiation | |||
protection | |||
technicians | |||
have been trained on these new procedures... | have been trained on these new procedures... | ||
There was-insufficient | There was-insufficient extremity monitoring and no procedures for | ||
extremity | |||
monitoring | |||
and no procedures | |||
particle control. As a corrective measure, procedures have been | |||
prepared to address particle control. Additional extremity moni- toring is being utilized. | |||
Evaluation of radiological events needs to be improved. A'new-pro'' | |||
cedure will be prepared for documenting and evaluating radiologicalj : | |||
events.- | |||
Review of radiation protection activities.'is insufficient. A new | |||
separate onsite review committee will be established to evaluate | |||
radiological events and to routinely review the performance of the | |||
Radiation Protection Department. - | |||
Insufficient staffing existed. Increasing the manpower in both the | |||
onsite Radiation Protection Department and the corporate Radiological | |||
Safety Branch of the Nuclear Safety and Regulation Department is being | |||
pursued. | |||
Attachment 1 IN 87-39 August 21, 1987 Problems existed due to insufficient radiation monitoring and surveying | |||
equipment. Additional equipment including new portal monitors and | |||
radiation monitoring equipment has been procured. | |||
There was the potential for radiation exposure to individuals from fuel | |||
particles on anti-contamination clothing. An evaluation for potential | |||
exposure is in progress. | |||
V. C. Summer, November 1986, Inspection Report No. 50-395/86-22 After working-in a "clean" area where no protective clothing was required, contamination was detected on the hand of an electrician who had worked on a | |||
control panel for the overhead crane in the fuel handling building. After | |||
measuring the dose rates (window open and window closed) with a portable survey | |||
instrument the worker's hand was decontaminated. The contaminant was not | |||
retained for further analysis. Based on the survey instrument readings, the | |||
dose to the workers hand was calculated to be about 420 rems (at a depth of | |||
7 mg/cm 2 2 averaged over an area of 1 cm ). | |||
- | Salem Unit 2, April 1987, Inspection Report No. 50-311/87-11 A fuel particle was detected by a whole-body contamination monitor on a work- er's arm. The particle was identified as a fuel particle (about 225 days since | ||
in core) by using a gamma-ray spectrometer [Ge(Li) detector]. The licensee | |||
the | believes that the source of the particle was from the last refueling outage | ||
about 8 months earlier. | |||
Yankee Nuclear Power Station, May 1987, Inspection Report No. 50-29/87-10 | |||
A potential skin exposure of 7.6 rem to a worker's scalp occurred from an | |||
activated particle. The apparent source of the particle was the worker's PC | |||
hood. After its discovery, the particle remained on the worker's scalp for | |||
about 78 hours, awaiting medical assistance to remove the particle. Prior to | |||
medical assistance arriving on site, the particle was removed by shaving the | |||
hair. Earlier in May, the licensee reported that, during fuel assembly move- ment, pieces of fuel rods were seen to have fallen away from the assembly and | |||
land on top of the reactor core and in the refueling cavity area. Fuel recon- stitution was in progress. - | |||
Attachment 1 IN 87-39 August 21, 1987 Indian Point Unit 3, May 1987, Inspection Report No. 50-286/87-18 A maintenance foreman exiting the containment after helping to replace steam | |||
generator manway covers received an estimated 4 rem dose to the skin (in back | |||
and | of neck) from an activated zirconium particle. It appears the particle dis- lodged from his PC hood and fell on his neck during temporary removal of the | ||
hood during a work rest-break. | |||
Quad Cities/Dresden/Zion, 1986 and 1987 A special program to investigate hot particle incidents has been in place at | |||
these Commonwealth Edison Company facilities for the last 1-2 years. A total | |||
of approximately 100 individual hot particles were found on workers' skin or | |||
clothing in 1986. Approximately 130 particles were found in the first six | |||
months of 1987. The particles have been predominantly Co-60 with activities | |||
ranging from about 0.01 to 1 pCi. Those particles were analyzed for physical | |||
size; the smallest was 20 microns. The licensee investigated each event and | |||
calculated skin doses. No overexposures have been reported. The transfer | |||
mechanism of the particles to the workers has not been positively identified. | |||
Callaway Station, 1986 Period, Report No. 50-483/8700 (DRSS) | |||
The licensee experienced ten hot particle skin contamination incidents primari- ly during the refueling outage early during the year. No NRC dose limits were | |||
exceeded. Ineffective frisking (hand-held pancake GM-tube) of laundered PC and | |||
potentially degraded dry-cleaning fluid quality (leading to cross-contami- nation of PC during cleaning) were identified by the licensee as possible | |||
contributors to this contamination problem. | |||
Attachment 2 IN 87-39 August 21, 1987 LIST OF RECENTLY ISSUED | |||
INFORMATION NOTICES 1987 | |||
===Information Date of=== | |||
Notice No. Subject Issuance Issued to | |||
87-38 Inadequate or Inadvertent 8/17/87 All nuclear power | |||
Blocking of Valve Movement reactor facilities | |||
holding an OL or CP. | |||
the | 87-37 Compliance with the General 8/10/87 All persons specifi- License Provisions of cally licensed to | ||
10 CFR Part 31 manufacture or to | |||
initially transfer | |||
devices containing | |||
radioactive material | |||
to general licensees, as defined in 10 CFR | |||
Part 31. | |||
87-36 Significant Unexpected 8/4/87 All nuclear power | |||
Erosion of Feedwater Lines reactor facilities | |||
holding an OL or CP. | |||
87-35 Reactor Trip Breaker, 7/30/87 All nuclear power | |||
Westinghouse Model DS-416, reactor facilities | |||
Failed to Open on Manual holding an OL or | |||
Initiation from the Control CP employing W DS-416 Room reactor trip breakers. | |||
87-34 Single Failures in Auxiliary 7/24/87 All holders of an | |||
Feedwater Systems OL or a CP for | |||
pressurized water | |||
reactor facilities. | |||
87-33 Applicability of 10 CFR 7/24/87 All NRC licensees. | |||
to | Part 21 to Nonlicensees | ||
87-32 Deficiencies in the Testing 7/10/87 All nuclear power | |||
of Nuclear-Grade Activated reactor facilities | |||
Charcoal. holding an OL or CP. | |||
87-31 Blocking, Bracing, and 7/10/87 All NRC licensees. | |||
Securing of Radioactive | |||
Materials Packages in | |||
Transportation. | |||
. : | |||
OL = Operating License | |||
CP = Construction Permit | |||
- .V IN 87-XX | |||
August, 1987 No specific action or written response is required by this information notice. | |||
If you have any questions about this matter, please contact the Regional | |||
Administrator of the appropriate regional office or this office. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
===James E. Wigginton, NRR=== | |||
(301) 492-4663 John 0. Buchanan, NRR | |||
(301) 492-7293 References | |||
Notice 86-23, "Excessive | 1. IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986. | ||
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987. | |||
3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel | |||
Cladding Failure Events on Occupational Radiation Exposures at Nuclear | |||
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986. | |||
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From | |||
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final | |||
Report, August 1983. | |||
5. Wells, J., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a | |||
Workshop held at Saclay, France, on October 9-11, 1985, Brit. | |||
J. Radiology, Supplement No. 19, pp. 146-150 (1986). | |||
6. Charles, M. W,., "The Biological Bases of Radiation Protection Criteria for | |||
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta | |||
Particles and Low Energy X-Rays," Proceedings of a Workshop held at | |||
Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No. | |||
2), pp. 79-90 (1986). | |||
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and Recent | |||
No. | Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. 69-81 (1986). | ||
Attachments: | |||
1. Events Summaries | |||
2. List of Recently Issued NRC Information Notices | |||
*SEE PREVIOUS CONCURRENCES p g C | |||
/OGCB:DOEA:NRR | |||
z UERidlHBerlinger | z UERidlHBerlinger | ||
RBDE-R | RBDE-R | ||
R P:NR '*D:DREP:NRR | PN R n 1 847 4 S8//' 87 8/ /87 RPB:DREP:NRR *RP:DREP:NRR R P:NR '*D:DREP:NRR *PPMB:ARM | ||
JEWigginton JDBuchanan LJCunningham FJCongel TechEd | |||
7/28/87 7/28/87 7/28/87 7/28/87 7/28/87 | |||
IN 87-XX | |||
August, 1987 No specific action or written response is required by this information notice. | |||
If you have any questions about this matter, please contact the Regional | |||
Administrator of the appropriate regional office or this office. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Contact: | |||
===James E. Wigginton, NRR=== | |||
(301) 492-4663 John D. Buchanan, NRR | |||
(301) 492-7293 References | |||
Skin Exposures | 1. "IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986. | ||
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987. | |||
of | 3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel | ||
Cladding Failure Events on Occupational Radiation Exposures at Nuclear | |||
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986. | |||
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From | |||
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final | |||
Report, August 1983. | |||
5. Wells, J., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a | |||
Workshop held at Saclay, France, on October 9-11, 1985, Brit. | |||
J. Radiology, Supplement No. 19, pp. 146-150 (1986). | |||
6. Charles, M. W., "The Biological Bases of Radiation Protection Criteria for | |||
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta | |||
and | Particles and Low Energy X-Rays," Proceedings of a Workshop held at | ||
Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No. | |||
2), pp. 79-90 (1986). | |||
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and | |||
Recent Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. | |||
69-81 (1986). | |||
Attachments: | |||
1. Events Summaries | |||
2. List of Recently Issued | |||
NRC Information Notices | |||
*SEE PREVIOUS CONCURRENCES D/DOEA:NRR C/OGCB:DOEA:NRR | |||
CERossi CHBerlinger | |||
8/ /87 8/10/87 | |||
*RPB:DREP:NRR *RPB:DREP:NRR *AC:RPB:DREP:NRR *D:DREP:NRR *PPMB:ARM | |||
JEWigginton JDBuchanan LJCunningham FJCongel TechEd | |||
7/28/87 7/28/87 7/28/87 7/28/87 7/28/87 | |||
~'V IN 87-XX | |||
August, 1987 No specific action or written response is required by this information notice. | |||
If you have any questions about this matter, please contact the Regional | |||
Administrator of the appropriate regional office or this office. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Contact: | |||
===James E. Wigginton, NRR=== | |||
(301) 492-4663 John D. Buchanan, NRR | |||
(301) 492-7293 References | |||
Exposures | 1. "IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986. | ||
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987. | |||
3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel | |||
Cladding Failure Events on Occupational Radiation Exposures at Nuclear | |||
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986. | |||
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From | |||
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final | |||
Report, August 1983. | |||
Aspects," Proceedings | 5. Wells, J., "Problems Associated With Localized Skin Exposures,' in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a | ||
Workshop held at Saclay, France, on October 9-11, 1985, Brit. | |||
No. 19, pp. 146-150 (1986). | J. Radiology, Supplement No. 19, pp. 146-150 (1986). | ||
Bases of Radiation | 6. Charles, M. W., "The Biological Bases of Radiation Protection Criteria for | ||
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta | |||
Particles and Low Energy X-Rays," Proceedings of a Workshop held at | |||
Radiation | Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No. | ||
2), pp. 79-90 (1986). | |||
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and | |||
Recent Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. | |||
69-81 (1986). | |||
Attachments: | |||
1. Events Summaries | |||
2. List of Recently Issued | |||
NRC Information Notices | |||
C/OGCB:DOEA:NRF | |||
CHBerlinger | CHBerlinger | ||
R i EP:NRR | R i EP:NRR RPM :NRR A REP:NRR D:DREP:NRRI | ||
JEigginton J. an LJC I4nningham FJCongel Techd | |||
7/&X/87 7/ig/87 7}(%/87 -4/ti/8 7 7/w}} | |||
{{Information notice-Nav}} | {{Information notice-Nav}} |
Latest revision as of 04:00, 24 November 2019
! . . - . i
V' 'SINS No.: 6835 iN 87-39 UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555 August 21, 1987 NRC INFORMATION NOTICE NQ. 87-39: CONTROL OF HOT PARTICLE CONTAMINATION
AT NUCLEAR POWER PLANTS
Addressees
storage facilities holding
All nuclear power reactor facilities and spent fuel
an NRC license or a construction permit.
Background and
Purpose
information on events in- IE Information Notice 86-23 (Reference 1) provided skin contamination by small, volving excessive skin exposures resulting from activity (hot particles). Since
highly radioactive particles with high specific been more of these events, and a
that information notice was issued, there have Operations (INPO) (Reference 2)
recent report by the Institute of Nuclear Power This information notice pro- provides additional information on this subject. and discusses degraded fuel
vides information on some of the subsequent eventsfuel reconstitution as major
and a lack of proper radiological control during learned also are included.
sources of hot particles. Generic licensee lessons
information for applicability
It is expected that recipients will review this to preclude a similar
to their facilities and consider action, if appropriate, suggestions contained in this
problem occurring at their facilities. However, no specific action or
notice do not constitute NRC requirements; therefore, written response is required.
Discussion:
hot particle exposures were
During the first 6 months of 1987, events involving Two events in late 1986 (at
reported at nine different nuclear power stations. exceeding NRC regula- V.C. Summer and San Onofre) involved exposures apparentlyof eight of these
tory limits. Attachment 1 provides summary descriptions from the referenced inspec- events. More detailed descriptions can be obtained Reports are available
tion reports for each event. (Copies of NRC Inspection Washington, D.C.)
from the NRC Public Document Room, 1717 H Street N.W.,
degraded fuel and neutron- Hot particles come primarily from two major sources: While much of the
activated corrosion and wear products (e.g., Stellite). corrosion
information in this notice is pertinent to both neutron-activated
as activated particles) and
and wear product particles (hereafter referred to
K> QIN 87-39 August 21, 1987 irradiated fuel particles (hereafter referred
to as fuel particles), a major
concern of this notice is extended facility operation
the resulting problems with fuel particle contamination. with degraded fuel and
NRC review of licensees' corrective actions, discussions On the basis of an
operating staffs, and information obtained by with licensees'
NRC inspectors, the lessons
learned and licensee good practices resulting
from the events summarized in
Attachment 1 are as follows:
1. Extended power plant operation with degraded fuel
result in widespread dispersal of fuel particles. (leaking fuel pins) can
experience fuel particle contamination problems Some plants continue to
pins have been removed because of the residual long after leaking fuel
systems. Some plants with these problems have contamination of plant
for missing fuel pellets and fragments and to started programs to account
identify measures to recover
this material.
2. Considerations concerning the handling of leaking
following: fuel include the
a. Special techniques and precautions for handling
are necessary to prevent aggravating the spread leaking fuel bundles
For example, containment devices should be used of fuel particles.
fuel. The lack of proper radiological controls when reconstituting
fuel reconstitution process in the San Onofre and oversight of the
3 fuel pool led to loss
of control and dispersal of numerous fuel particles
Fuel particles then spread through the plant spent into the pool.
to the liquid radwaste systems. fuel systems and
b. A damaged, leaking fuel pin that is not properly
segregated from the common fuel pool area could contained and
long-term source of fuel particle contamination. be a significant, c. Plants should be aware that NSSS vendors' special
refueling tools and
equipment could be a source of fuel particle contamination.
tools and equipment should be carefully surveyed These
and before they are shipped to other facilities. before they are used
3. Some plants that have operated for extended periods
fuel and plants with activated particle problems of time with degraded
specialized, comprehensive training programs for now have instituted
workers and general employees. These programs plant system maintenance
inform and prepare the plant staff to cope with are designed to better
particle problems. Additionally, as part of the continuing fuel
comprehensive
control programs, special new procedures to improve contamination
surveys for detection
- --
. .IN 87-39 August 21, 1987 of.hot particles have been prepared and health physics technicians have
been trained in their use. Decontamination and dose evaluation methods
and procedures that focus on hot particles have been implemented. (See
summaries of events at Trojan and.San Onofre in Attachment 1.)
.4.. In general, ;licensees have upgraded their programs for contamination
monitoring of "clean," laundered anti-contamination protective clothing
(PC). However, PC continues to be a means of transferring both fuel
particles and activated particles. Some facilities need to consider
making their PC monitoring programs more sensitive. For example, some
licensees that are using contractor laundry services found the contrac- tor's alarm on the radiation monitor (used to screen PC) too high to
-detect 0.4 microcurie (VCi) particles. Moreover, when commercial plant laundry
services are used, it is possible that PC from a "particle-free"
- *-can be mixed with PC from a plant with hot particle problems. Finally, at.leastrone licensee was relying solely on monitoring of large bundles
of washed PC (bulk surveys) and was not monitoring samples of individual
PC. For plants with identified particle problems, individual PC items
may have to be checked before they are reused after cleaning.
5. Except for the-Trojan event discussed in Attachment 1, to date, no
licensee has reported detecting hot.particles during airborne sampling.
However, as a precaution,,some licensees have elected to provide workers
with respiratory protection for performing maintenance on plant systems
known to-be a source of hot particles. No plant has reported inhalation
or ingestion of hot particles by any worker.
6. Hot particles in contact with skin.produce very high dose rates. Diligent
personnel contamination surveys performed as soon as practical after .
completing work involving contamination are needed to minimize potential
exposure times.-
7. Approximately 75 percent of the U.S. power reactor facilities are cur- rently using new high-sensitivity whole-body contamination monitors.
These state-of-the-art contamination monitors increase the probability of
detecting hot-particles on plant personnel while reducing the likelihood
of inadvertently releasing particles from the plant site. To-date, most
of-the particles found on personnel have:been detected by these new
monitors. Even with use of the new monitors, a few instances have oc- curred where hot particles have inadvertently been carried home by workers
. and have-been detected in the home or on the worker returning to the site.
No significant ,public exposures have been reported to date.
8. In a recent study for the NRC (Reference 3), it was reported that a plant
operating with 0.125 percent pin-hole fuel cladding defects showed a
general five-fold increase in whole-body radiation exposure rates in some
IN 87-39 .
August 21, 1987 areas of the plant when compared to a sister plant with
fuel (<0.01percent leakers). Around certain plant systems high-integrity
fuel may elevate.-radiation exposure rates even more. the degraded
-
9. Maintenance-on valves with Stellite components can cause
cobalt-containing debris with Co-60 as the resultant introduction of
product. Some plants have instituted work controls (e.g.,neutron activation
ment and post-maintenance cleaning) to minimize this input use of contain- systems (Reference 4). into reactor
Health Implications and Radiation Protection Criteria
for Hot Particle- Exposures of Skin: -
A hot'particle on the skin gives a high beta dose to
a small area.' Any radia- tion dose to the skin is-assumed to result in'some increased
cancer, although'this type of cancer is rarely fatal.' risk of skin
indicate that highly localized irradiation of-the skin'by Experiments with animals
likely to'cause skin cancer than more uniform irradiation hot particles is less
of radioactive material.:- by the same quantity
In addition to any increased risk of cancer, large
particles also may produce observable effects such doses to the skin from hot
as reddening, hardening, peeling, or ulceration of the skin-immediately around
effects appear only'after a-threshold dose is exceeded.the particle; These
particles 'equired to-produce these effects'in the 'skin The doses from hot
cisely;-Ihowever, -it appears likely, except for a point are'not known pre- effects will only be seen for doses of hundreds of rems reddening,-that these
effects have been seen to date on any workers who have or more.'- No such
particles, even though one exposure has been measured been exposed to-hot
512 rem. or calculated as high as
Recent reviews of radiobiology and radiation protection
cluding considerations of hot particle exposures, have criteria for skin, in- been provided-by-Wells
(Reference 5) and Charles (References 6 and 7).
The NRC staff recognizes the need for more'information
radiation on skin and particularly the effects-of hot on the effects of
The staff has requested the National Council on Radiation particle irradiation.
Measurements (NCRP) to. study the health significance of Protection and
and to provisde recommendations- based on the findings of hot particle exposures
recommendations may result in changes in NRC requirements this study. These
particle exposures. However, until these requirements with respect to hot
are changed, IE Infor- mation Notice 86-23 (Reference 1) contains current information
evaluating doses to skin resulting from hot particles. for use in
./ .. IN 87-39 August. 21, 1987 Page 5 of S
oI specific action or.written response is required by this information notice.
- you have any questions about this matter, please contact the Regional
Admiistrator 'f the appropriate regional office or this office.
e,
.harles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technwcal Contact:- James E..Wigginton, NRR
(301) 492-4663 John D. Buchanan, NRR
.(301) 492-7293 References
I. JAE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tihn With Hot Particles," April 9, 1986.
2i. nstitute of Nuclear Power Operations, Significant Event Report 18-87 (Rev..2), "Radiation Exposure From Small Particles," July 16, 1987.
3,- Hoeller; M. P., :G. F. Martin, and D. L..Haggard, "The Impact of Fuel
- -Cladding Failure Events on Occupational Radiation Exposures at Nuclear
- PowerPants. Case Study: PWR During RoutineOperations," NUREG/CR-4485 (PNL-5606), January 1986.
Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From
H4
.`Valve IMaintenance," Electric Power Research Institute, EPRI NP-3220, Final
- Report, August 1983. .
5.. Welli, 3., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a
. Workshop. heldat Saclay, France, on October 9-11, 1985, Brit.
.J3. Radiology, Supplement No. 19, pp. 146-150 (1986).
- .6. Charles, 4.W., "The Biological Bases of Radiation Protection Criteria for
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta
Particles and Low Energy X-Rays," Proceedings of a Workshop held at
Sacay, Francei October 7-9,-1985," Radiation Protection Dosimetry 14 (No.
-
79-90 (1986).
P2),pp.
-7. Charles, 14. W., "Skin, Eye, and Testis: Current Exposure Problems and Recent
. .Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. 69-81 (1986).
Attachments;.. ..
-l.*. EventSummaries
.2.. List-4f Recently Issued NRC Information Notices
Attachment 1 IN 87-39 August 21, 1987 EVENT SUMMARIES
San Onofre 3. Events Durina November 1986 - March 1987, Inspection Report
No. 50-362/86-37 Background:
At the onset of the first fuel cycle, significant fuel degradation was evident.
The plant continued to operate with approximately 105 defective fuel pins. In
late 1985 during the first refueling outage, a fuel pin was inadvertently
pulled apart during the fuel reconstitution process. Several fuel pellets fell
and dispersed throughout the fuel pool. Fuel particles had previously been
detected early on during reconstitution on fuel handling tools and on the
refueling floors. All the severely damaged fuel pins were then grouped into
one fuel bundle and stored in the pool without any containment.
Event Specifics:
From January 2 through February 20, 1987, the licensee's aggressive hot parti- cle inventory and tracking system indicated that 92 "new" fuel particles
(recently neutron irradiated), 155 "old" fuel particles, 51 ruthenium, 84 crud, and 42 cobalt particles had been found and analyzed. Before 1987, no formal
tracking program existed.
Several incidents involving hot particles have occurred, including an apparent
worker extremity exposure (hand) of 512 rem during November 1986. As a result, appropriate NRC enforcement actions are currently underway. Three events
involving the inadvertent release of hot particles from the plant site occurred
in February 1987. In two of these events, the radiation dose to the public was
determined to be negligible. However, the third event involved a 0.2.;Ci
particle found by a worker at his home during a self-initiated radiological
survey. The licensee has not yet estimated the potential dose to the worker's
family as a result of this occurrence.
In the licensee's licensee event report (LER No.86-015, Revision 1) of Febru- ary 22, 1987, the following program improvements for detecting hot particles
and controlling personnel exposures from hot particles were described:
f
Extensive, mandatory use of exceedingly sensitive fixed instrumentation
(frisking booths) for the detection of personnel contamination;
Special training (including hands-on laboratory exercises) in radioactive
particle characteristics and survey techniques for all Health Physics
Technicians;
C-.
Attachment 1 IN 87-39 August 21, 1987 Oral and written indoctrination of all managers, first line super- visors and workers in the special problems associated with radio- active particles, including the methods each person must employ to
protect himself;
Special procedures to assure detection and control of radioactive
particles which feature the establishment of a clearly identifiable
zone, to demark and contain such particles, surrounded by clearly
identified buffer zones (or solid physical barriers) which are
surveyed frequently to verify that control is being maintained;
Maintenance and wide publication of a radioactive particle census
during outages to maintain station awareness;
The establishment of a Task Force to recommend and implement action to
minimize the future production and movement of radioactive particles.
Trojan, April, 1987, Inspection Report No. 50-344/87-15 Background:
The facility has operated since July 1982 with an estimated 112 fuel pellets
unaccounted for throughout the reactor and support plant systems. The licensee
recovered or located about 264 pellets of the estimated 376 missing after the
1982 refueling outage, which occurred because of the baffle jetting problems of
the 1981 fuel cycle. (See IE Information Notice 82-27, "Fuel Rod Degradation
Resulting From Baffle.Water-Jet Impingement," August .5, 1982.)
Event Specifics:
Shortly after the start of the 1987 refueling outage in April, a significant
increase in personnel skin contaminations occurred. On April 9, high surface
contamination (up to 300,000 dpm/100 cm2) and high airborne activity levels
-.(2E-7 pCi/cc, mixed fission products) in containment resulted from the dis- persal of fuel fragments during reactor vessel. stud removal and stud-hole
plugging operations. The workers in the reactor cavity were wearing respira- tors and no excessive uptakes of.radioactive materials were detected during
followup whole-body counting. Because of the spread of contamination to the
spent fuel building, the licensee stopped all- reactor building cavity work and
all personnel evacuated the area that afternoon.
On April 10, a licensee radiation survey located a hot spot on the cavity floor
near a reactor vessel stud-hole (>100 rad/hr beta and 30 R/hr gamma contact
reading using a portable ion-chamber survey.instrument). On April 11, another
worker located what appeared to be about one-half of a fuel pellet in the
flange area at the stud hole. This partial fuel pellet was removed on
April 12.
Attachment 1 IN 87-39 August 21, 1987 On April 17, a radiation protection technician, after performing a survey of
the lower refueling cavity, discovered a fuel particle lodged in his protective
rubber shoe cover. This particle was later determined to be composed of
approximately 50 mCi of mixed fission product activity; showed readings of 1200
mR/hr with the window open and 250 mR/hr with the window closed. After a
careful time-and-motion study of the technician's activities, the licensee
determined that no NRC regulatory dose limits were exceeded. (Licensee esti- mates were 1.2 rem to whole body; 4.6 rem to skin; 9.6 rem to extremities.)
In general, it appears that the licensee experienced a programmatic breakdown
that resulted in several workers receiving significant, unnecessary radiation
exposures from fuel particle contamination. In LER No. 87-08'dated May 8, 1987, the licensee identified the following additional concerns and'corrective
actions. The LER stated in part:
Workers entering containment on April 9 were not-aware of the fuel
particle hazards. As a corrective measure, all personnel with
access to radiological control areas were retrained to be informed of
the fuel particle problem and perform hands-on training to demonstrate
competence in anti-contamination clothing use. Daily reports
are being provided to workers on the status of containment activities.
Radiation surveys and record keeping were inadequate. As a corrective
measure, new procedures were developed to specifically address
discrete radioactive particles. All radiation protection technicians
have been trained on these new procedures...
There was-insufficient extremity monitoring and no procedures for
particle control. As a corrective measure, procedures have been
prepared to address particle control. Additional extremity moni- toring is being utilized.
Evaluation of radiological events needs to be improved. A'new-pro
cedure will be prepared for documenting and evaluating radiologicalj :
events.-
Review of radiation protection activities.'is insufficient. A new
separate onsite review committee will be established to evaluate
radiological events and to routinely review the performance of the
Radiation Protection Department. -
Insufficient staffing existed. Increasing the manpower in both the
onsite Radiation Protection Department and the corporate Radiological
Safety Branch of the Nuclear Safety and Regulation Department is being
pursued.
Attachment 1 IN 87-39 August 21, 1987 Problems existed due to insufficient radiation monitoring and surveying
equipment. Additional equipment including new portal monitors and
radiation monitoring equipment has been procured.
There was the potential for radiation exposure to individuals from fuel
particles on anti-contamination clothing. An evaluation for potential
exposure is in progress.
V. C. Summer, November 1986, Inspection Report No. 50-395/86-22 After working-in a "clean" area where no protective clothing was required, contamination was detected on the hand of an electrician who had worked on a
control panel for the overhead crane in the fuel handling building. After
measuring the dose rates (window open and window closed) with a portable survey
instrument the worker's hand was decontaminated. The contaminant was not
retained for further analysis. Based on the survey instrument readings, the
dose to the workers hand was calculated to be about 420 rems (at a depth of
7 mg/cm 2 2 averaged over an area of 1 cm ).
Salem Unit 2, April 1987, Inspection Report No. 50-311/87-11 A fuel particle was detected by a whole-body contamination monitor on a work- er's arm. The particle was identified as a fuel particle (about 225 days since
in core) by using a gamma-ray spectrometer [Ge(Li) detector]. The licensee
believes that the source of the particle was from the last refueling outage
about 8 months earlier.
Yankee Nuclear Power Station, May 1987, Inspection Report No. 50-29/87-10
A potential skin exposure of 7.6 rem to a worker's scalp occurred from an
activated particle. The apparent source of the particle was the worker's PC
hood. After its discovery, the particle remained on the worker's scalp for
about 78 hours9.027778e-4 days <br />0.0217 hours <br />1.289683e-4 weeks <br />2.9679e-5 months <br />, awaiting medical assistance to remove the particle. Prior to
medical assistance arriving on site, the particle was removed by shaving the
hair. Earlier in May, the licensee reported that, during fuel assembly move- ment, pieces of fuel rods were seen to have fallen away from the assembly and
land on top of the reactor core and in the refueling cavity area. Fuel recon- stitution was in progress. -
Attachment 1 IN 87-39 August 21, 1987 Indian Point Unit 3, May 1987, Inspection Report No. 50-286/87-18 A maintenance foreman exiting the containment after helping to replace steam
generator manway covers received an estimated 4 rem dose to the skin (in back
of neck) from an activated zirconium particle. It appears the particle dis- lodged from his PC hood and fell on his neck during temporary removal of the
hood during a work rest-break.
Quad Cities/Dresden/Zion, 1986 and 1987 A special program to investigate hot particle incidents has been in place at
these Commonwealth Edison Company facilities for the last 1-2 years. A total
of approximately 100 individual hot particles were found on workers' skin or
clothing in 1986. Approximately 130 particles were found in the first six
months of 1987. The particles have been predominantly Co-60 with activities
ranging from about 0.01 to 1 pCi. Those particles were analyzed for physical
size; the smallest was 20 microns. The licensee investigated each event and
calculated skin doses. No overexposures have been reported. The transfer
mechanism of the particles to the workers has not been positively identified.
Callaway Station, 1986 Period, Report No. 50-483/8700 (DRSS)
The licensee experienced ten hot particle skin contamination incidents primari- ly during the refueling outage early during the year. No NRC dose limits were
exceeded. Ineffective frisking (hand-held pancake GM-tube) of laundered PC and
potentially degraded dry-cleaning fluid quality (leading to cross-contami- nation of PC during cleaning) were identified by the licensee as possible
contributors to this contamination problem.
Attachment 2 IN 87-39 August 21, 1987 LIST OF RECENTLY ISSUED
INFORMATION NOTICES 1987
Information Date of
Notice No. Subject Issuance Issued to
87-38 Inadequate or Inadvertent 8/17/87 All nuclear power
Blocking of Valve Movement reactor facilities
87-37 Compliance with the General 8/10/87 All persons specifi- License Provisions of cally licensed to
10 CFR Part 31 manufacture or to
initially transfer
devices containing
radioactive material
to general licensees, as defined in 10 CFR
Part 31.
87-36 Significant Unexpected 8/4/87 All nuclear power
Erosion of Feedwater Lines reactor facilities
87-35 Reactor Trip Breaker, 7/30/87 All nuclear power
Westinghouse Model DS-416, reactor facilities
Failed to Open on Manual holding an OL or
Initiation from the Control CP employing W DS-416 Room reactor trip breakers.
87-34 Single Failures in Auxiliary 7/24/87 All holders of an
Feedwater Systems OL or a CP for
pressurized water
reactor facilities.
87-33 Applicability of 10 CFR 7/24/87 All NRC licensees.
Part 21 to Nonlicensees
87-32 Deficiencies in the Testing 7/10/87 All nuclear power
of Nuclear-Grade Activated reactor facilities
Charcoal. holding an OL or CP.
87-31 Blocking, Bracing, and 7/10/87 All NRC licensees.
Securing of Radioactive
Materials Packages in
Transportation.
. :
OL = Operating License
CP = Construction Permit
- .V IN 87-XX
August, 1987 No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the Regional
Administrator of the appropriate regional office or this office.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
James E. Wigginton, NRR
(301) 492-4663 John 0. Buchanan, NRR
(301) 492-7293 References
1. IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986.
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987.
3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel
Cladding Failure Events on Occupational Radiation Exposures at Nuclear
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986.
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final
Report, August 1983.
5. Wells, J., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a
Workshop held at Saclay, France, on October 9-11, 1985, Brit.
J. Radiology, Supplement No. 19, pp. 146-150 (1986).
6. Charles, M. W,., "The Biological Bases of Radiation Protection Criteria for
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta
Particles and Low Energy X-Rays," Proceedings of a Workshop held at
Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No.
2), pp. 79-90 (1986).
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and Recent
Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp. 69-81 (1986).
Attachments:
1. Events Summaries
2. List of Recently Issued NRC Information Notices
- SEE PREVIOUS CONCURRENCES p g C
/OGCB:DOEA:NRR
z UERidlHBerlinger
RBDE-R
PN R n 1 847 4 S8//' 87 8/ /87 RPB:DREP:NRR *RP:DREP:NRR R P:NR '*D:DREP:NRR *PPMB:ARM
JEWigginton JDBuchanan LJCunningham FJCongel TechEd
7/28/87 7/28/87 7/28/87 7/28/87 7/28/87
IN 87-XX
August, 1987 No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the Regional
Administrator of the appropriate regional office or this office.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
James E. Wigginton, NRR
(301) 492-4663 John D. Buchanan, NRR
(301) 492-7293 References
1. "IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986.
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987.
3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel
Cladding Failure Events on Occupational Radiation Exposures at Nuclear
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986.
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final
Report, August 1983.
5. Wells, J., "Problems Associated With Localized Skin Exposures," in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a
Workshop held at Saclay, France, on October 9-11, 1985, Brit.
J. Radiology, Supplement No. 19, pp. 146-150 (1986).
6. Charles, M. W., "The Biological Bases of Radiation Protection Criteria for
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta
Particles and Low Energy X-Rays," Proceedings of a Workshop held at
Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No.
2), pp. 79-90 (1986).
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and
Recent Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp.
69-81 (1986).
Attachments:
1. Events Summaries
2. List of Recently Issued
NRC Information Notices
- SEE PREVIOUS CONCURRENCES D/DOEA:NRR C/OGCB:DOEA:NRR
CERossi CHBerlinger
8/ /87 8/10/87
- RPB:DREP:NRR *RPB:DREP:NRR *AC:RPB:DREP:NRR *D:DREP:NRR *PPMB:ARM
JEWigginton JDBuchanan LJCunningham FJCongel TechEd
7/28/87 7/28/87 7/28/87 7/28/87 7/28/87
~'V IN 87-XX
August, 1987 No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the Regional
Administrator of the appropriate regional office or this office.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
James E. Wigginton, NRR
(301) 492-4663 John D. Buchanan, NRR
(301) 492-7293 References
1. "IE Information Notice 86-23, "Excessive Skin Exposures Due to Contamina- tion With Hot Particles," April 9, 1986.
2. Institute of Nuclear Power Operations, Significant Event Report 18-87 (Rev. 2), "Radiation Exposure From Small Particles," July 16, 1987.
3. Moeller, M. P., G. F. Martin, and D. L. Haggard, "The Impact of Fuel
Cladding Failure Events on Occupational Radiation Exposures at Nuclear
Power Plants. Case Study: PWR During Routine Operations," NUREG/CR-4485 (PNL-5606), January 1986.
4. Heard, D. B., and R. J. Freeman, "Cobalt Contamination Resulting From
Valve Maintenance," Electric Power Research Institute, EPRI NP-3220, Final
Report, August 1983.
5. Wells, J., "Problems Associated With Localized Skin Exposures,' in "Radia- tion Damage to Skin: Fundamental and Practical Aspects," Proceedings of a
Workshop held at Saclay, France, on October 9-11, 1985, Brit.
J. Radiology, Supplement No. 19, pp. 146-150 (1986).
6. Charles, M. W., "The Biological Bases of Radiation Protection Criteria for
Superficial, Low Penetrating Radiation Exposure," in "Dosimetry of Beta
Particles and Low Energy X-Rays," Proceedings of a Workshop held at
Saclay, France, October 7-9, 1985," Radiation Protection Dosimetry 14 (No.
2), pp. 79-90 (1986).
7. Charles, M. W., "Skin, Eye, and Testis: Current Exposure Problems and
Recent Advances in Radiobiology," J. Soc. Radiol. Prot. 6 (No. 2), pp.
69-81 (1986).
Attachments:
1. Events Summaries
2. List of Recently Issued
NRC Information Notices
C/OGCB:DOEA:NRF
CHBerlinger
R i EP:NRR RPM :NRR A REP:NRR D:DREP:NRRI
JEigginton J. an LJC I4nningham FJCongel Techd
7/&X/87 7/ig/87 7}(%/87 -4/ti/8 7 7/w