How to Perform a Radiation Survey on a Loaded Gamma Projector

If you’re handling a gamma projector, be it coming in through your transport or coming off the rig onto the job site, the first thing you should do is perform a radiation survey. It doesn’t matter how it looks from the outside. The only way to confirm it's safe and ready is to check the dose rates yourself.

This quick guide outlines how to properly survey a loaded gamma projector before use. It's not just protocol. It's your first line of defense.

Why the Initial Survey Matters

Before any radiographic work begins, a survey confirms the unit’s shielding is intact and the source is secure. Survey results help detect potential shielding issues or unintended source exposure due to internal faults, damage during transport, or source misalignment. Radiation levels must be within acceptable limits to protect you, your team, and anyone else in the area. This step is also required for regulatory compliance. Failure to conduct the survey properly can lead to operational delays, citations, or worse.

Step-by-Step Survey Procedure

1. Use a calibrated survey meter. Make sure you're using an appropriate survey meter for the isotope type and energy level. In this video, we’re using the Tracerco T-402 survey meter.
2. Verify radiation levels are below 200 mR/hr on contact at all surfaces, including:
   1. Front side (outlet port)
   2. Rear side (lock mechanism)
   3. Around the full circumference
   4. Bottom surface (tip the unit on its side to access)
3. Stand one meter from the projector and confirm the reading is below 10 mR/hr. This verifies the dose rate at 1 meter is within regulatory limits for safe handling and transport, as outlined in U.S. NRC and IAEA transport safety standards.

What to Do if the Readings Are Off

If any of your measurements exceed the limits, stop work immediately ^{[1] [2]}. Don’t assume it's safe. Notify your Radiation Safety Officer or supervisor and have the projector evaluated before it’s used, and follow your facility’s safety protocols.

Why We Emphasize Survey Techniques

Our commitment to safety extends beyond providing high-quality equipment. We want to ensure that every technician working with QSA Global products has the knowledge and skills to operate safely. Proper survey techniques are fundamental to protecting yourself and others while maximizing productivity with our radiography systems.

Sources

1. S. Nuclear Regulatory Commission (NRC). 10 CFR Part 34 – Licenses for Industrial Radiography and Radiation Safety Requirements for Industrial Radiographic Operations.
2. International Atomic Energy Agency (IAEA). Regulations for the Safe Transport of Radioactive Material: 2018 Edition, SSR-6 Rev. 1

Note: This guide focuses on initial survey procedures only. Additional safety protocols, emergency procedures, and specific regulatory requirements may apply based on jurisdiction and facility requirements. Always consult applicable safety manuals and regulatory guidelines for complete requirements.