Ionising radiation is invisible, odourless and tasteless. A radiographer who has worked in an X-ray department for ten years has no way of knowing — without measurement — whether they have received a significant radiation dose over that period. This is why personal dosimetry exists. In the UAE, FANR requires all classified radiation workers to wear individual dosimeters and have their doses recorded throughout their working career. TLD (Thermoluminescent Dosimeter) badges are the most widely used technology for this purpose in UAE healthcare. This article explains how TLD dosimetry works, who needs it, and what the regulatory requirements are.
A Thermoluminescent Dosimeter (TLD) badge contains small crystals — typically lithium fluoride (LiF) — that absorb energy from ionising radiation and store it in a metastable state. When the crystals are subsequently heated in a laboratory instrument called a TLD reader, they release the stored energy as visible light. The amount of light emitted is proportional to the radiation dose the crystal absorbed.
This process is highly accurate, reproducible, and sensitive to doses as low as 0.1 mSv — well below the thresholds of regulatory concern. TLD badges are passive — they require no power, no maintenance and no calibration by the user. They are simply worn during working hours and sent to the laboratory for reading at the end of the monitoring period.
Under FANR regulations, a classified radiation worker is any person who, as part of their normal work, is liable to receive an annual effective dose exceeding 1 mSv — the dose limit for members of the public. In UAE healthcare, this typically includes:
• Diagnostic radiographers • Radiologists who perform fluoroscopy-guided procedures • Interventional cardiologists and vascular surgeons • Theatre staff in C-arm fluoroscopy cases • Nuclear medicine technologists • Radiation therapy radiographers • Dental radiographers (in high-workload practices) • Biomedical engineers who service X-ray equipment without adequate protective measures
Staff who work in offices adjacent to X-ray rooms, or who only rarely enter controlled areas, are generally not classified radiation workers and do not require personal dosimetry.
TLD (Thermoluminescent Dosimeter) and OSL (Optically Stimulated Luminescence) dosimeters are the two main technologies used for personal dosimetry in UAE healthcare. Both are highly accurate and FANR-acceptable.
TLD advantages: Established technology, widely available, robust, cost-effective for large programmes. TLD disadvantages: The reading process is destructive — once read, the information cannot be retrieved again.
OSL advantages: Non-destructive reading — the badge can be re-read multiple times, which is valuable if there is a question about a dose reading. The OSL element can also be archived for years and re-read if needed. OSL disadvantages: Slightly higher cost than TLD.
RevirzaMed offers both TLD and OSL dosimetry programmes. For facilities with complex workloads or a history of dose investigation queries, OSL is recommended.
The most common monitoring periods in UAE healthcare are:
Monthly: Recommended for high-workload areas such as interventional radiology, cardiac catheterisation laboratories and CT scan departments. Monthly reporting allows rapid identification of elevated doses and investigation before the next monitoring period.
Quarterly: Appropriate for general X-ray departments and dental practices. The slightly longer period is acceptable because workloads are lower and large acute dose events are less likely.
Annual: Not recommended for any active radiation worker. Annual reporting means a significant dose event could go undetected for up to twelve months.
FANR sets investigation levels for occupational radiation doses. When a worker's dose in a monitoring period exceeds these levels, an investigation is mandatory. RevirzaMed's dosimetry service includes automated alerts when doses exceed investigation thresholds, and our radiation safety team can assist with the investigation process — reviewing the worker's duties, the equipment's performance, and the shielding and working practices to identify the cause and implement corrective action.
FANR requires dose records to be maintained for the duration of a radiation worker's career and for a minimum period after they leave the organisation. When a radiation worker changes employer, their dose history should be transferred to the new employer to allow lifetime dose assessment. RevirzaMed maintains complete dose records for all workers on our dosimetry programme and can produce FANR-compliant dose history reports on request.
TLD badges should be replaced at the end of each monitoring period — monthly or quarterly depending on your programme. Wearing an overdue badge that has not been sent for reading is a compliance violation and means dose data for that period is lost.
FANR follows IAEA recommendations. The occupational effective dose limit is 20 mSv per year averaged over 5 consecutive years, with no single year exceeding 50 mSv. For the lens of the eye, the limit is 20 mSv per year. For the extremities, 500 mSv per year.
Individual facilities rarely have the laboratory equipment needed to read TLD badges — this requires a TLD reader, nitrogen gas supply, calibration sources and trained operators. In practice, facilities use a managed dosimetry service like RevirzaMed's, which handles badge supply, reading, reporting and dose record management.
RevirzaMed Healthcare Solutions — Abu Dhabi's trusted FANR Approval and medical equipment specialists since 2015.