The following was received by the state of
North Carolina by email:
On 5/1/2017, licensee received a 5 gallon shielded drum containing 8 Cf-252 sources with a total activity of 148 MBq (4.0 mCi). Shipment of the sources originated from E&Z Isotope Products, License Number: 1509-19. Shipment was made through [a common carrier]. The drum was labeled Yellow-III and had a TI [Transport Index] of 9.4. The licensee followed procedures for receiving and securing radioactive materials shipments. Once the drum was secured, the licensee noted surveys of the drum were higher than expected:
Side survey of the drum was 18 mrem/hr (gamma) on contact and 90 mrem/hr (neutron) for a total of 108 mrem/hr.
Top survey of the drum was 40 mrem/hr (gamma) on contact and 400 mrem/hr (neutron) for a total of 440 mrem/hr.
Bottom survey of the drum was 3 mrem/hr (gamma) on contact and 20 mrem/hr (neutron) for a total of 23 mrem/hr.
The drum was then shielded with polyethylene and cadmium. Upon resurveying the drum to confirm readings the following differences were noted: With the drum upright and the neutron detector on top of the drum, the reading was 400 mrem/hr. With the drum on its side and the neutron detector in contact with the drum, the reading was 440 mrem. Wipes of the drum were then taken and the results were [less than] MDL (Minimum Detectable Levels).
The drum was then opened for further inspection by the licensee. It was noticed that a polyethylene bag containing sources was sitting on top of the shield plug and was only about 2 inches from the top of the drum and not covered by any shielding indicating that the sources were not shielded correctly prior to shipment.
The sources were in-processed by the licensee and are still in the licensee's possession (quantity and activity as approved per their NC License).
North Carolina Radiation Protection, [the common carrier] and E&Z Isotope Products were notified of the event on 5/1/2017.
NC Radiation Protection is actively investigating this event at this time.
Report ID Number (NC): NC170020
At this time the cause and corrective action is to be determined. NC Radiation Protection will be reaching out to E&Z Isotope Products and [the common carrier] for more information. The licensee was authorized to receive the materials in the quantity and activity they received.