Plan, classify and assess
Identify the source or equipment, radiation type, intended activity and applicable work category. Complete the risk assessment and approved safe work procedure, applying elimination or substitution where practicable.
Radiation work lifecycle
Manage radiation work from planning to close-out
Apply these controls throughout the lifecycle. Requirements depend on the source or equipment, activity, exposure potential, people and facility.
Licence and authorise
Obtain every applicable institutional, apparatus and user licence before purchase, acquisition or use. Confirm the required training, competency, medical examinations and exposure-monitoring arrangements.
Acquire, receive and prepare
Purchase or receive the source or equipment only after authorisation. For radioactive materials, submit purchases through LMPRS; on receipt, verify the material and documentation, then record and manage the inventory in LMMS. Confirm facility, storage and emergency readiness.
Use, control and monitor
Apply time, distance, shielding, containment, interlock, controlled-area and access controls appropriate to the work. Complete required surveys, dosimetry, leak tests and licence records. Maintain and track inventory, waste generation and decay.
Respond, report and review
Establish and follow emergency procedures for suspected / confirmed exposure, contamination, loss or theft of radioactive material or equipment failure. Obtain medical attention where required, report through AIMS, and review the risk assessment and controls.
Transfer, dispose and close out
Obtain approval before transfer or disposal. Reconcile licence records and, for radioactive materials, update the LMMS inventory following transfer, disposal, return or removal from use. Decontaminate affected areas and equipment, and complete source, equipment, project or facility decommission requirements.
Programme scope
Find the requirements for your work
Use the lifecycle above for every project, then select all categories below that apply. One activity may require several licences, courses and controls.
Radioactive materials and sealed sources
Applies to: unsealed radioactive materials and equipment containing radioactive sources, including gauges and gamma irradiators.
Check or obtain: the applicable R1 user licence and IR2 possession licence through GoBusiness, plus approved storage, inventory, contamination controls, monitoring, leak testing and disposal arrangements.
Ionising radiation · R1 / IR2 licencesX-ray-producing equipment
Applies to: X-ray machines and equipment capable of producing ionising radiation, including relevant analytical and imaging systems.
Check or obtain: apparatus and user requirements, shielding, controlled-area arrangements, equipment checks and exposure controls.
Ionising radiation · apparatusClass 3B and Class 4 lasers
Applies to: open-beam and embedded laser systems where users may be exposed to a Class 3B or Class 4 beam.
Check or obtain: applicable apparatus and user licences, controlled-area arrangements, engineering controls, eyewear and training.
Non-ionising radiation · N2/N3MRI and other non-ionising radiation
Applies to: MRI controlled areas and other regulated non-ionising apparatus, including high-power ultrasound equipment.
Check or obtain: task-specific risk controls, access arrangements, operator competency and applicable apparatus requirements.
MRI · other non-ionising apparatusSSTS Stage B
Radiation and laser safety training
Complete the course matching the equipment or source used. Three-year refreshers apply to the core laser, radioactive-material and X-ray courses.
Laser Safety Training
OSHRAD02Core · CompulsoryFor activities involving Class 3B or Class 4 lasers.
Safe Handling of Radioactive Materials
OSHRAD03Core · CompulsoryFor activities using radioactive materials or equipment containing them, such as gauges and gamma irradiators.
Effective from 11 September 2017Safe Handling of X-ray Machines
OSHRAD04Core · CompulsoryFor individuals using X-ray machines or equipment capable of producing X-rays.
Effective from 11 September 2017Basic MRI Safety Training
OSHRAD05Add-on · CompulsoryFor people accessing an MRI controlled area but not operating MRI machines or scanners.
Effective from 1 June 2016MRI Safety Training for Operators
OSHRAD06Add-on · CompulsoryFor people accessing MRI controlled areas and operating MRI machines or scanners.
Effective from 1 June 2016Tools and documents
Radiation safety resources
Resources are grouped by purpose. NUS documents may require sign-in.
Safety manuals
Licence and application guides
Ionising radiationRadiation User Licence (R1) Application GuideNUS sign-inPDFNon-ionising apparatusN2 Apparatus Licence Application GuideNUS sign-inPDFLaser userN3 User Licence Application GuideNUS sign-inPDFLaser exemptionFlow Chart to Apply for NEA N3 Licence Exemption for Use of Confocal MicroscopesNUSPDFApplication portalGoBusiness LicensingExternal websiteRegulatory guidanceNEA Guidelines for Licence Application and Annual PaymentExternal website
Records and forms
Occupational healthOccupational Health Services Authorisation FormNUS sign-inPDFWaste Generation and Decay TrackingNUS Radioactive Material Clearance Declaration FormNUS sign-inPDFContamination SurveyRadioactive Material User Monthly Survey FormNUS sign-inPDFLeak Test (Sealed Source)Sealed Source Leak Test ReportNUS sign-inPDFSafety reviewRadioactive Sealed Source Safety Review FormNUS sign-inDOCX
Common questions
Radiation safety FAQs
Where do I apply for radiation user licences?
Submit applications through GoBusiness Licensing and use the relevant NUS application guide for ionising radiation or laser user licences.
Where should I go for the required medical examination?
Arrange the examination with the Occupational and Diving Medicine Centre at the University Health Centre. Book online or contact OHClinic@nus.edu.sg / 6601 1781.
Which lasers require licences?
Class 3B and Class 4 lasers require an N2 licence to keep or possess each laser, and an N3 licence for each user. This includes embedded systems where a user may be exposed to the Class 3B or Class 4 beam.
Are TEM and SEM systems exempt from licensing?
They are exempt only when the equipment is not primarily intended to produce ionising radiation and does not exceed 5 µSv per hour at 5 cm from an accessible surface. Manufacturer conformity or radiation-test evidence is required.
Need help?
Radiation safety contacts
Choose the contact responsible for your enquiry.
ORMC radiation safety enquiriesFor ionising and non-ionising radiation programme enquiries.
rmcsec@nus.edu.sgEmail ORMC
rmcsec@nus.edu.sgEmail ORMC
Medical examinationsOccupational Health Clinic
OHClinic@nus.edu.sg
6601 1781Email OH Clinic
OHClinic@nus.edu.sg
6601 1781Email OH Clinic