sealedsource

Sealed sources are radioactive materials permanently encapsulated in a capsule or fixed in a solid matrix to prevent dispersion of radioactive material during normal use or under foreseeable conditions. The encapsulation provides mechanical and leak-tight containment, allowing the source to be handled with shielding and remote manipulation while minimizing exposure risk. Sealed sources are designed for long-term use and are intended to be reused, periodically inspected, and replaced when degraded or expired.

There are several encapsulation forms, including metal capsules, glass enclosures, or resin-encapsulated pellets. The activity and half-life determine the configuration and shielding requirements. Sealed sources are designed to contain the radioactive material under normal handling and during transportation, and they are tested to confirm the integrity of the containment.

Common uses include industrial radiography, well-logging, and calibration of instruments, as well as brachytherapy in medicine and, in some models, smoke detectors. Isotopes such as Ir-192, Co-60, Cs-137, I-125, Pd-103, and Am-241 are typical examples, chosen based on radiation type and energy. Devices that use sealed sources are designed with shielding and interlocks to enhance safety and to limit exposure during operation and handling.

Safety and regulatory considerations are central to sealed sources. Their manufacture, handling, storage, transport, and disposal are subject to radiation-safety regulations and licensing requirements in many jurisdictions. Routine quality assurance includes leak testing and integrity checks; sources are tracked and controlled to prevent loss, contamination, or diversion.

Lifecycle management includes proper disposal or recycling when a source expires or is decommissioned, typically through licensed facilities or supplier return programs. Secure storage, inventory controls, and transport compliance are essential to responsible use.