Radiation Safety

The University has two Radioactive Substances Licences for possession and use of Sealed Radioactive Substances and Unsealed Radioactive Substances respectively. The activities (or the maximum quantities to be handled) and locations of individual sources are clearly specified in the licences.

Removal of any source out of its specified location or purchase of any source not stated in the licences is a violation to the law. Hence, if a user plans to purchase any radioactive source not stated in the licence or to relocate any radioactive source to other location for whatever reason, they should notify HSO to apply to the Radiation Board for approval.

Users of either sealed or unsealed RS shall register with HSO and be trained in radiation safety.

For unsealed sources, both classroom training and online training are required while for sealed sources, online training alone may be acceptable.

Besides, the person responsible for managing radioactive sources of his department, known as the Radiation Protection Supervisor, must complete a certificate course in radiation safety organized by an institution which has been accredited by the Radiation Board.

Users of unsealed RS are required to take pre-employment and annual medical examinations to prove they are fit for radiation work. Their radiation dosage shall be monitored with Thermoluminescent Dosimeter (TLD).

It is a legal requirement to obtain a licence from the Radiation Board, HKSAR for possession or use of irradiating apparatus. A list of the relevant licences are given below for reference.

• Possession of an irradiating apparatus in a NON-FUNCTIONAL state (for on-site installation/commissioning of x-ray machines by the supplier)
• Possession of an irradiating apparatus in a FUNCTONAL state
• Storage of irradiating apparatus or x-ray tube
• Use of irradiating apparatus on human body
• Use of irradiating apparatus not on human body

It is the responsibility of individual department to apply to the Radiation Board for the above licences and the subsequent annual renewal.

HSO will help the department to go through the process. The user department must notify HSO at the planning stage before the procurement process is initiated.

For open-beam IA, individual operators must apply for an operator licence from the Radiation Board and register with HSO. The operators must be trained in radiation safety and their radiation dosage be monitored with Thermoluminescent Dosimeter (TLD).

For closed-beam IA, operators must be trained in radiation safety and registered with HSO. (Certain closed-beam IAs may require the operator to possess an operator licence from the Radiation Board. You may check the licencing conditions given in the IA licence for details.)

For research projects which may involve the use of radioactive source or irradiating apparatus, the concerned Principal Investigators shall obtain Research Safety Approval from the Research Safety Sub-committee before the commencement of the project.

To ensure safe use of ionizing radiation sources, HSO provides the following services:

• Advise on the safe design of radiation laboratory
• Advise on the safe use of radiation sources
• Advise and support on the application of licences from the Radiation Board
• Operating a Radiological Dosimetry Laboratory (accredited by the Radiation Board) for regular area contamination monitoring and leakage tests for radiation sources
• Managing two Radioactive Substances Licences
• Managing an online database system for the management of radioactive substances and irradiating apparatus of the University
• Managing an online radiation users registration system
• Provide safety training for radiation users
• Arrangement of medical surveillance for radiation users
• Monitoring of personal radiation dosages and background radiation levels
• Decontamination service in the event of radiation spill

A. Irradiating Apparatus (IA) Procurement Procedures

• Seek advice and obtain approval from HSO before purchasing any irradiating apparatus.
• After PO is issued and before delivery, user department needs to apply for a temporary license (non-functional state) from the Radiation Board.
• After installation, user department needs to apply for an operation license (functional state) from the Radiation Board.
• Radiation Board inspector shall inspect the IA and the premises, and issue the license upon satisfaction.
• User department needs to register the licenced IA with HSO.

B. Radioactive Substance (RS) Procurement Procedures

• Seek advice and obtain HSO approval before initiating the procurement process (Licence amendment is usually required).
• If licence amendment is required, HSO will arrange it with the Radiation Board, and notify the user department to proceed with the procurement once the amendment application is approved by the Radiation Board.
• After the RS is received, user department shall notify HSO for checking and send the required documents (e.g. wipe test certificates, DG declaration, Airway bill, delivery note, etc.) to HSO. HSO will then compile and send these documents to the Radiation Board for completion of registration.