Industrial radiography source exchange: a project checklist

Industrial radiography source exchanges happen on a routine schedule — typically every 1 to 3 years depending on isotope, activity, and operational tempo. They're routine in the sense that everyone in industrial radiography has done them many times. They're also one of the most regulator-sensitive operations a radiography licensee performs, and the cost of getting any detail wrong is high: license violations, financial penalties, and (in worst cases) physical security incidents.

This checklist covers the full source-exchange project, from initial planning through receipt of the new source. It's not a substitute for your written operating procedures, your license, or the specific guidance from your supplier — but it's a practical operating reference for the radiographer or RSO managing the project.

Phase 1: Planning (4 to 8 weeks before exchange)

Confirm the current source's identification details. Pull the source certificate, the current sealed source and device (SS&D) registration certificate, and the National Source Tracking System (NSTS) record. Verify that all three documents are consistent — radionuclide, activity, serial number, manufacturer, date of original delivery. Any discrepancy here is a red flag that needs to be resolved before you proceed.

Confirm the new source specifications. Get the SS&D registration certificate for the new source from the supplier. Verify radionuclide (typically Ir-192 or Se-75 for industrial work), activity at calibration date, model number, and certificate number. Confirm that the new source fits your existing exposure devices — this should be obvious, but mismatches happen when projects are managed across multiple operating crews.

Schedule the exchange with your supplier. Industrial source suppliers in the US are a small, mature market — typically QSA Global, Source Production & Equipment Co., or one of a handful of smaller specialty suppliers. Lead times for source delivery are typically 4 to 8 weeks from order placement to scheduled delivery. Plan accordingly.

Schedule the disposal of the spent source. Most source exchanges are handled as a source-out, source-in transaction with the same supplier — your spent source goes back to the supplier for disposition (typically reprocessing or storage by the manufacturer) at the same time the new source arrives. Confirm the disposal pathway with the supplier explicitly. Get the paperwork (NRC Form 540, 541, 542 series or state equivalent) lined up before the transaction.

Verify license authority for the planned activity. Your radiography license specifies a maximum activity for each isotope. If the new source's activity is higher than your license authority, you need an amendment first. License amendments for activity increases typically take 30 to 60 days and require a written justification — don't surprise yourself at the last minute by discovering you're over your license limit.

Verify radiographer certifications. The personnel performing the source exchange — typically your senior radiographer or RSO — must be currently certified under 10 CFR Part 34 or your state equivalent. Verify that certifications haven't lapsed.

Phase 2: Pre-exchange (1 to 2 weeks before)

Notify the licensing authority if required. Some states require advance notification of source exchanges; NRC generally does not, but check your specific license conditions. If your license requires advance notice, submit it in writing with the planned exchange date.

Prepare the receipt documentation. Have ready: the SS&D certificate for the new source, the supplier's calibration certificate, the bill of lading, and the chain-of-custody documentation. These need to be inventoried and filed within a specific time window after receipt (typically within 5 business days for NRC licensees; check your state for variations).

Prepare the storage location. The new source will go directly from the delivery vehicle into your exposure device. The empty exposure device should be staged at the receipt location, the keys and security devices verified, and the storage area secured. Don't store an industrial radiography source — even briefly — outside an approved exposure device.

Brief the receiving crew. The radiographer or RSO receiving the source needs to know the planned arrival window, the delivery driver's contact information, the chain-of-custody procedures, and the security requirements during transfer. This is a 15-minute conversation, but it has to happen.

Coordinate security. Industrial radiography sources are Category 2 sources under NRC's 10 CFR Part 37 — they require specific security measures during transit and at the receipt location. Verify the supplier's transit security and your facility's receipt security are both adequate and documented.

Phase 3: Exchange day

Receive the new source per the standard receipt protocol. Document the delivery time, the chain-of-custody transfer, and the physical inspection of the shipping container.

Perform the source change-out per your written procedure. The change is performed at the device (typically a Sentinel 880-series or similar exposure device). The crank assembly is disconnected, the spent source pigtail is withdrawn into the source tube, the source tube is detached, the new source tube is attached, and the new source pigtail is connected. The full procedure typically takes 30 to 60 minutes including the surveys before and after.

Survey the device after exchange. A leak test of the new source is required within 6 months of installation; most operators do it on installation day to simplify recordkeeping. Document the survey results, the source serial numbers (old and new), and the time of exchange.

Update the NSTS record. The transfer of the old source out and the receipt of the new source need to be reported through the National Source Tracking System within 5 business days. This is a routine online submission but it's a regulatory requirement, not an option.

Update your sealed source inventory. Add the new source to your inventory with all required fields (radionuclide, activity, serial number, SS&D number, location, responsible individual). Remove the old source. The inventory should be reconcilable to your license at all times.

Coordinate the spent source pickup. The spent source goes back to the supplier — typically on the same trip as the new source delivery, but sometimes on a separate logistics arrangement. Confirm the chain-of-custody for the outbound source, the bill of lading, and the security requirements during return transit.

Phase 4: Post-exchange (1 to 2 weeks after)

File the receipt documentation in your radiation safety records. The SS&D certificate, the supplier's calibration certificate, the bill of lading, the chain-of-custody documentation, and the leak test results all belong in your records and need to be retained for the life of the source plus a regulator-specified period after disposal.

Update your radiographer training records. The crew involved in the exchange should have the exchange noted in their training and experience records.

Update your written operating procedures if needed. If anything in the exchange revealed a gap in your procedures — a step that was missing, a contingency that wasn't covered, a piece of equipment that didn't work as expected — update the procedure now. Don't wait for the next exchange to discover the same gap again.

Notify customers if relevant. If your operations involved customer projects that were paused during the exchange, notify them that operations have resumed with the new source. Provide the new source's SS&D number if they require it for their own records.

The regulatory traps to avoid. The top sources of citation in source exchanges: NSTS submission missed or late (a strict requirement and inspectors check it); leak test not performed or not documented within the required window; inventory not updated promptly, creating a discrepancy between physical sources on hand and listed sources; chain-of-custody documentation gaps during transit; security measures during receipt or transit not following the documented procedure.

All five are avoidable with the checklist above. The exchange itself is routine work; the documentation discipline around it is what separates compliant operators from cited ones.

The relationship to your license category. Industrial radiography licensees are inspected on a regular cadence — typically every 1 to 3 years. Inspectors review source exchange documentation as part of every inspection. A well-documented exchange that follows the checklist above is essentially uninspectable. A poorly-documented exchange is a finding waiting to happen.

If you've never managed a source exchange and you're about to, work with your supplier's radiation safety team — they've done thousands of these and can walk you through any specific questions for your facility. Use this checklist as a structured reference, but defer to your written procedures and your supplier's guidance for the specific details of your operation.