Regulatory Disclosures: 2000- 2009

Operational limits and conditions were exceeded in the medical isotope production area of ARI by acquiring activity in excess of licence conditions.

A proposed change to the OPAL shift roster was initially categorised as not needing formal ARPANSA approval. However, ARPANSA were notified of the proposal in line with transparent reporting. ARPANSA requested formal approval be sought for the change. Proposal postponed while formal approval sought.

When an OPAL instrument failed operators were unable to change settings on the faulty instrument within time allowed under operating licence. The signal continued to be monitored by back-up systems. Monitoring was of neutron flux levels during start-up mode. Reactor was at full power. Staff considered they were operatong correctly under source licence. The component was replaced as quickly as possible and analysis of the event showed that the reactor was always in a safe state.

ARPANSA determined on 18 February 2010 that ANSTO failed to observe an OPAL operating licence condition. ANSTO is currently considering its response. Notified to ARPANSA in quarterly report and remedial actions implemented. Determination of breach accepted.

Several staff were concerned that employees may have been exposed when a vial was dropped in a shielded cell during radiopharmaceutical production transfer. No exposure above normal occupational levels was recorded. An employee raised the matter at the Central Safety Co-ordinating Committee in May 2009 and further investigations occurred including one by ARPANSA. No exposure in excess of normal occupational levels was detected. ARPANSA found that there was no significant exposure.

April 2007 A spillage of Yttrium-90 within a contained enclosure led to a finger dose in excess of the statutory limit, but below any threshold for associated health effects.

An employee received a dose of Iodine-123 when packing medical isotopes for patient use. The dose was 4% of the annual limit for radiation workers. Due to the low- level notification to ARPANSA was not required.

A pipe rupture occurred within a shielded enclosure during production of the medical isotope Technitium-99m. There was no impact to any employee. ARPANSA and Comcare were notified.

Calibration of a monitor was not properly maintained at the Gamma irradiation facility.

At the Camperdown cyclotron medical isotope production facility an inter-cell door jammed and damaged an in-cell rail causing exposure to an employee. In a separate incident an employee got trace contamination on hair and clothing. Contamination was immediately removed. The exposures were below ANSTO’s limits and within normal occupational exposure levels.

11 Aug

2005 

Personnel at the Camperdown cyclotron received a small quantity of contamination on their clothing during medical isotope production. Decontamination occurred promptly. There was no measurable radiation dose or impact on their health.

Dosimeter worn by a radiopharmaceutical technician indicated an effective dose of 66 millisieverts – equivalent to five abdominal CT scans. The statutory limit is 20 mSv annually with ANSTO’s self-imposed constraint as 15 mSv. The allowable limit was exceeded. The employee was reassigned to non-radioactive duties as a precaution Possible explanation for high reading on dosimeter may be from it being left near a radioactive source for an extended period.

ARPANSA observed the hois during a periodic inspection. The hois was subsequently removed.

Licence requirements were breached when personnel did not undertake heavy water plant room check resulting in employee contamination from Tritium of 2.33 millisieverts effective dose. The statutory limit is 20 mSV annually. ANSTO’s self-imposed constraint is 15 mSv.

A HIFAR fuel rod was partially cut during cropping in a fuel pool within a building. There was light contamination on clothing of an employee and radioactive particles also entered the pool. The ARPANSA investigation noted two dead birds outside the pool. Testing showed trace radioactive elements at levels which were not a health or environmental concern. Traces of employee clothing contamination required clean up at several locations including off site. All resulting exposures were low and not of health concern.