Radiation Safety

The University holds two Radioactive Substances Licences for possession and use of Sealed Radioactive Substances and Unsealed Radioactive Substances respectively. Permitted activities (or 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 of the law. Hence, if a user plans to purchase any radioactive source not stated in the licence or to relocate any radioactive source to another location for any reason, they must notify HSO to apply to the Radiation Board for approval.

Users of either sealed or unsealed Radioactive Substances (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 individual responsible for managing radioactive sources of his or her department, known as the Radiation Protection Supervisor, must complete a certificate course in radiation safety organized by an institution 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 must be monitored with Thermoluminescent Dosimeter (TLD).

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

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

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

HSO helps departments navigate this process. User department must notify HSO at the planning stage before the procurement process is initiated.

For open-beam irradiating apparatus (IA), individual operators must apply for an operator licence from the Radiation Board and register with HSO. Operators must be trained in radiation safety, and their radiation dosage must 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 involving use of radioactive sources or irradiating apparatus, Principal Investigators concerned must obtain Research Safety Approval from the Research Safety Sub-committee before commencement of the project.

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

• Advise on safe design of radiation laboratories
• Advise on safe use of radiation sources
• Advise and support on the application for licences from the Radiation Board
• Operate a Radiological Dosimetry Laboratory (accredited by the Radiation Board) for regular area contamination monitoring and leakage tests for radiation sources
• Manage two Radioactive Substances Licences
• Manage an online database system for the tracking of radioactive substances and irradiating apparatus across the University
• Manage an online radiation user registration system
• Provide safety training for radiation users
• Arrange medical surveillance for radiation users
• Monitor personal radiation dosages and background radiation levels
• Deliver decontamination service in the event of a radiation spill

A. Irradiating Apparatus (IA) Procurement Procedures

• Seek advice and obtain approval from HSO before purchasing any irradiating apparatus
• Apply for a temporary licence (non-functional state) from the Radiation Board after Purchase Order (PO) is issued and before equipment delivery
• Apply for an operating licence (functional state) from the Radiation Board immediately after installation is completed
• Coordinate with the Radiation Board inspector to examine the IA and premises; the Radiation Board will issue formal licence upon satisfactory inspection
• Register the licences IA with HSO once the operating licence is secured

B. Radioactive Substance (RS) Procurement Procedures

• Seek advice and obtain approval from HSO before initiating procurement process, as a licence amendment is usually required
• Await confirmation from HSO, who will arrange the licence amendment with the Radiation Board and notify user department to proceed with procurement once approval is granted
• Notify HSO for inspection immediately after the RS is received
• Submit all required documents, such as wipe test certificates, dangerous goods (DG) declarations, air waybills and delivery notes to HSO. HSO will then compile and forward these documents to the Radiation Board for official registration