Describe how radioactive materials are moved, used and stored in a safe way

5.2.5 Safety Precautions

Objective

Describe how radioactive materials are moved, used and stored in a safe way.

Key Principles of Radiation Protection

• Time – minimise the time spent near a source.
• Distance – increase the distance from the source; radiation intensity follows the inverse‑square law \$I \propto \frac{1}{r^{2}}\$.
• Shielding – place appropriate material between the source and the user.

Moving Radioactive Materials

1. Plan the route in advance; avoid high‑traffic areas and keep the path as short as possible.
2. Use a lead‑lined container or a shielded trolley. The container should be clearly marked with the radiation symbol.
3. Carry the source at arm’s length; if possible, use a remote handling tool (tongs, forceps) to increase distance.
4. Wear personal protective equipment (PPE) – lab coat, gloves, and a dosimeter badge.
5. Inform all personnel in the vicinity before moving the source.

Using Radioactive Materials

• Controlled Area: Perform experiments in a designated radiation‑controlled area with warning signs.
• Shielding: Place the source behind a shield appropriate to its radiation type (e.g., lead for \$\gamma\$‑rays, acrylic for \$\beta\$‑particles).
• Collimation: Use collimators to direct the beam only where needed, reducing stray radiation.
• Monitoring: Use a Geiger‑Müller counter or scintillation detector to check radiation levels before, during, and after the experiment.
• Emergency Procedures: Have a spill kit and clear instructions for containment and decontamination.

Storing Radioactive Materials

Storage must prevent accidental exposure, contamination and loss of the source.

1. Store in a locked, lead‑lined cabinet that is vented for gases if the source emits them.
2. Keep an up‑to‑date inventory list, including activity, half‑life, and date of last inspection.
3. Separate sources by radiation type and activity level to avoid unnecessary shielding.
4. Maintain a minimum distance of 2 m from walls and other equipment; use shelving made of low‑density material to avoid additional shielding.
5. Inspect containers regularly for damage; replace seals and shielding as required.

Shielding Materials and Recommended Thicknesses

Procedural Checklist for Safe Handling

1. Verify the source’s activity and half‑life from the inventory.
2. Confirm that the appropriate shielding and PPE are available.
3. Perform a pre‑use radiation survey of the work area.
4. Use remote handling tools whenever possible.
5. Record the time of exposure and update dosimeter readings.
6. After use, place the source back in its shielded container and secure the lock.
7. Conduct a post‑use radiation survey and document any anomalies.