Preliminary Dose Assessment for Emergency Response Exercise Using Unsealed Radioactive Contamination

Area of Science:

• Radiological Sciences
• Nuclear Safety
• Emergency Preparedness

Background:

• Emergency response exercises are crucial for preparedness.
• Accurate dose assessment is vital for safety during such exercises.
• Unsealed radioactive sources present unique challenges for dose estimation.

Purpose of the Study:

• To perform a preliminary dose assessment for an emergency response exercise.
• To determine safe activity levels for unsealed radioactive sources.
• To identify suitable radionuclides for exercise scenarios.

Main Methods:

• Utilized conservative calculation methods for dose assessment.
• Employed MicroShield computer code for external exposure calculations.
• Estimated internal exposure using fractional intakes and dose coefficients.

Main Results:

• A radionuclide-dependent activity range of 37 MBq to 1.5 GBq was established.
• Detectable dose rates can be achieved without exceeding administrative limits.
• Technetium-99m (Tc) resulted in the lowest dose among evaluated radionuclides.

Conclusions:

• Tc is recommended for radiological safety in exercises.
• The final choice of radionuclide and activity depends on budget and logistical factors.
• Conservative dose assessment ensures safety during radioactive source exercises.