1. Radiation Dosimeters

2. Radiation Dosimeters are used to measure Occupational exposure to Ionizing Radiation
The most common type of Radiation Dosimeter is the Thermo Luminescent Dosimeter
( TLD)

3. How does a TLD work?
When exposed to ionizing radiation the crystals in Thermoluminescent dosimeters or TLD’s undergo a structural change that remains essentially stable until the crystal is heated.  When heated, the stored
energy is released as light, which can be measured and related to the level of radiation exposure.
One crystal measures deep dose and one measures shallow dose.

4. There are 3 different types of dosimeters worn at LHSC
Radiation Dosimeters are assigned to be worn on specific areas of the body.
There are 3 different types of dosimeters worn at LHSC
Ring
Collar
Whole body

5. Whole Body Badge Location
Body badges measures dose to the main body trunk .
It should be worn on the clothing between the waist and chest.
When wearing a lead apron it
should be worn close to the skin under the lead protection.

6. Collar Badge Location
Collar badges measures the dose to the head . It is worn outside the thyroid collar during fluoroscopic procedures.
It measures the unshielded dose to the head.

7. Ring Badge Location
Your Ring Badge will come with your name on it. Wear the badge with the name plate facing the source of radiation.

8. Handling of Dosimeters
Dosimeters must be handled carefully.
They can not be exposed to
Water
Heat
Punctured
damaged

9. Accidental Exposures
Any accidental exposure to the TLD monitoring badge/ring should be reported immediately to the to the Radiation Safety Officer.

10. Damaged or Lost Badge
If you lose or damage your TLD monitoring badge/ring please report it immediately to the Radiation Safety Officer.
You will be then given a replacement

11. Dose Reports Include: All Dose Reports are reviewed by the
Dose readings by Badge Type
Collar
Whole body
Ring
Cumulative Dose History Current
Quarter
Year to date
Lifetime to date
                                   
All Dose Reports are reviewed by the
Radiation Safety Officer

12. Occupational Dose Limits for
Radiation Workers
Source of Radiation
Whole Body Dose should not to exceed
20 mSv/ yr

13. Occupational Dose to the Lens of the Eye
Dose should not exceed 150 mSv / yr

14. Occupational Exposure Limit to the Extremities
The Dose Limit to the Extremities should not exceed 150 mSv / yr

15. Occupational Dose Limit for Declared
Pregnant Mothers
Dose should not exceed 4 mSv during the gestation period for declared pregnant mothers.

16. Annual Dose Limit to a General Member of the Population
X-ray room
Should not exceed 1 mSv/yr

17. Points to Remember -Whole Body badges to be worn under lead aprons
-Collar badge to be worn
outside lead
If you lose/damage or
accidentally expose badge Please contact RSO/ supervisor
_ Do not expose your badge to water, heat

18. Contact the Radiation Safety Office
Questions
Contact the Radiation Safety Office
Ext 76576