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(iii) Assessment of Excessive Exposure 2.3 UNUSUAL OCCURRENCES AND
Cases for Radiation Facilities
ENFORCEMENT ACTIONS
Radiation dose to worker in excess of regulatory (i) Loss of Oil Well Logging Source
constraint of 10 mSv in a monitoring period is reported by
personnel monitoring service provider to AERB, which An oil-well logging container housing 137 Cs source
is communicated further to respective user institution for of activity 80 GBq (~2 Ci) belonging to a well logging
investigation. Such investigation reports are reviewed institute in Rajahmundry got lost on January 14, 2019
by AERB for not only assigning the dose to the worker during transport. Later on, this source container was
but also to initiate regulatory actions to prevent such recovered from a scrap dealer on January 23, 2019 with
recurrences. For resolution of such reported cases, the the efforts of Law Enforcement authorities, National
investigation report has to undergo through multi-tire Disaster Response Force (NDRF) and personnel from
review process in AERB. At present, depending upon well logging institute. No damage to the source container
the radiation dose, the report is reviewed by three safety and source assembly was observed. Subsequently,
committees. AERB officers visited the incident site and verified
the status of the source & sources container. It was
In the recent past, a large number of excessive established that incident occurred due to inadequate
exposure cases got accumulated for final resolution due security arrangements for the source.
to several reasons. One of the major reasons for which is
non-receipt of investigation reports with necessary inputs Enforcement Action:
from the user institution in-spite of multiple reminders.
It is worth noting that delay in resolution of excessive AERB issued a show-cause notice to the licensee
exposure cases defeats the purpose of personnel organisation. The incident was discussed in AERB Safety
monitoring in protecting the workers from unsafe work Review committee where representatives of licensee
practice, if any. To resolve these pending cases an In- organisation were also called for personal hearing.
House Review Group (IHRG) was constituted in AERB. Subsequently a warning letter was issued to licensee of
the organisation. Incident has been reported in IAEA-
Analysis of the previously investigated cases INES and Incident and Trafficking Database (ITDB).
shows that around 90% of the reported cases are from (ii) Use and Storage of Radiography Device
Diagnostic Radiology (DR) practice and out of the at Unauthorised Site
reported cases from DR practice, about 95% cases are
found to be non-genuine, where the persons were not AERB conducted surprise regulatory inspections
actually exposed to the reported radiation dose. Such during January 17-21, 2019 at various sites in Agra and
cases are mainly due to storage of TLD badge inside Rajkot and sealed four industrial radiography devices
the X-ray room, using the bare TLD card, wearing the (belonging to two different radiography facilities) for
TLD badge over lead apron (which normally reduced storage/use at unapproved/unauthorised sites.
the exposure level by around 90%). Keeping this in view
and based on the experience in resolution of excessive Enforcement Action:
exposure cases in the past, IHRG framed criteria for AERB issued show-cause notices to both the
resolution of excessive exposure cases.
radiography facilities. After review of responses from
Several steps were also initiated by AERB, including the facilities, AERB initiated enforcement actions by
spreading awareness to the workers about proper use of suspending operation of two devices for a period of
TLD and safe work practice, which resulted in reduction three months.
of excessive exposure cases in DR practice. Secondly, (iii) Theft of Industrial Radiography Device
the procedure of assessment of excessive exposure
cases have been revised for their expeditious resolution. A car carrying industrial radiography device model
With this multipronged approach not only the number Delta-880 containing 192 Ir source of about 1.53 TBq
of reported cases were reduced but also the reported (41.4 Ci) belong to Navi Mumbai based radiography
cases were expeditiously resolved to avoid further company met with an accident on June 26, 2019 near
accumulation in future. Pune. Post-accident, RSO of radiography agency reached

46 AERB Annual Report 2019