here - Atomic Energy Regulatory Board

3.4.1 Radioactive Contamination in Steel Products
Radioactive contamination was reported in steel
products exported to UK and US. It was noted that all the
shipment of contaminated steel products originated from
Kolkata. AERB conducted inspection of 20 factories
manufacturing engineering products in Kolkata for detection
of radioactive contamination in the steel products on the
request of Engineering Export Promotion Council, Eastern
Region, Kolkata and some of the manufacturing companies.
Some radioactive contaminated items were located and
safe disposal of the same was arranged. The manufacturing
units and exporters of steel products have been advised to
use the radiation monitoring equipment for detection of
radioactive contamination.
3.4.2 Other Unusual Occurrences
❖ Gamma radiation Processing Plant
➤ An incident resulting in misalignment of source
pencil occurred at one of the gamma radiation processing
plants due to improper design of source rack. AERB directed
the institution to suspend the operations of the facility and
submit a report on proposed action plan for rectification of
design deficiency responsible for the incident. The facility
was allowed to resume operation only after rectification of
the deficiency.
➤ An incident occurred at one of the gamma
radiation processing facilities involving the collision of
product carrier with I-Beam support for source shroud
leading to slippage of source hoisting wire ropes. This caused
the lowering of the source frame from its fixed position.
AERB has directed the facility to suspend operations and
submit a report on the proposed action plan for rectification
of design discrepancies, which caused the incident.
❖ Industrial Radiography
➤ An Industrial Gamma Radiography Exposure
Device (IGRED) model GAMMARID 192/120, Sr. No. 70,
weighing about 17 kg, containing about 0.5 TBq activity of
Ir-192 source was lost during transport in an auto-rickshaw.
The IGRED along with radiography accessories was being
carried by a trainee radiographer and his assistant for
carrying out radiography work at a place about 5 km away
from the device storage facility. En-route, they changed the
auto-rickshaw. In the process, they forgot to shift the
radiography device from the first auto-rickshaw to the
second. The radiography agency intimated the incident to
AERB after a week.
Search operations were launched with the help of
Police. Radiation detection surveys were carried out at
various locations near the incident site. The source could
not be recovered inspite of extensive search operations by
using high sensitivity radiation survey instruments. The
device has adequate shielding with proper locking
mechanisms to prevent inadvertent removal of the
radioactive source from the device. Since the radiography
source is safely housed inside IGRED, it may not cause any
significant radiological hazard to the members of the public.
Authorization for radiography work of the agency has been
withdrawn.
➤ An IGRED model Techops-660, Sr. No. 5785, with
0.29 TBq (~8 Ci) Ir-192 of a radiography agency was
stolen on 06-11-2006. The IGRED was kept outside dark
room area for use on the same day. However, the
radiography work got rescheduled and there was no
immediate radiography job to be carried out. As a result,
the IGRED was lying unattended outside the dark room
area. The workers of radiography agency found the IGRED
missing when it was needed for the radiography job.
Extensive radiation detection surveys, with the help
of local Police Authorities, were conducted at different areas
of the plant. However, the missing IGRED could not be
located. No radiation injury has been reported. The device
has adequate depleted Uranium shielding with proper locking
mechanisms to prevent inadvertent removal of the
radioactive source from the device and hence, the event is
considered to be insignificant from radiological safety point
of view.
The incident took place mainly due to negligence
of the certified radiographer of the agency as he left the
exposure device unattended. The authorization for
radiography work of the agency was withdrawn by AERB
and certificates of radiographer and site-in-charge involved
in the incident were withdrawn for a period of six months.
❖ Nucleonic Gauges
➤ On 12-10-2006, the oil well logging tool model
D4TG – DSNT – SED string with neutron source (19.5 Ci
Am-Be 241) got stuck up in the well that belongs to M/s.
ONGC, Assam Asset, Nazira. The complete tool with source
was fished out successfully on 15-10-2006. There is no
damage to source and it was fully secured.
➤ The ECIL make industrial ionizing radiation gauging
device (IRGD/nucleonic density gauge), model RDG4124B,
containing 9.2 GBq (~250mCi as on date) Cs-137 source
was found to be missing on 16-11-2006 from the premises
of one of the industrial institution. The overall weight of
this Gauge assembly is about 45 kg with lead shielding.
The above gauge was being used to measure the density of
liquids, suspensions, coal slurries or poured materials in
coal washery. However, the coal washery was not in
operation since 2003. It was reported that in the year 2005,
the electronic parts associated with this gauge were stolen,
but the nucleonic gauge assembly was intact.
The missing nucleonic gauge could not be located
despite the extensive radiation detection surveys, (with the
help of local Police authorities) at different areas of the
plant, and all scrap yard situated in the city area. It is
presumed that the source might be still inside the nucleonic
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