Under NRC regulations, a facility that wishes to possess and use certain nuclear gauges must have a license for that nuclear device. This license may either be a “general” or “specific” license.  A general license is typically less cumbersome and used by sites with few gauges.  A specific license can cover multiple gauges at a specific site and may allow for greater permissions to work with the gauges, but it also requires more initial paperwork and training. The NRC and most Agreement States allow both general and specific licenses.  Some agreement states, however, do not allow general licenses, requiring that all nuclear gauges be listed on a site specific license.

U.S. Nuclear Regulatory Commission

General License

A General License permits the facility to own and operate the gauge under certain conditions. The facility personnel can mount the shield and source to the applicable pipe or vessel with instructions provided by the manufacturer/distributor, and can perform the regulatory required maintenance. However, they are required to have a specifically licensed service technician on site to commission, decommission, and recommission the shield, which involve dose rate surveys and documentation prior to putting the shield into service, taking it out of service and dismounting the shield, and relocating to a new location, respectively.
A responsible party within the General Licensees company must be designated to maintain all documentation and records of regulatory required maintenance. Once delivered, Berthold will alert the regulatory body that the site has acquired a nuclear device, and the regulatory body will reach out to the site with a registration form which must be completed and paid annual. More information

Specific License

A Specific License is a license maintained by each company or site.  A specific license may allow the site  to conduct more gauge related activities while the device is owned. However, this depends entirely on the regulatory body and license terms and conditions. Activities such as moving the source from one location to another, commissioning the source upon initial installation, and performing non-routine maintenance (including removal and re-installation) may be approved under this license category.

A Radiation Safety Officer (RSO) is required for a specific license and must undergo the appropriate training to take program responsibility. The facility must have the specific nuclear device on their license prior to its delivery.  It is recommended the site RSO, in this role, report directly to the site general manager.

Regulatory Required Maintenance

An Operational Safety Test must be performed at minimum every 6 months. This requires checking the opening/closing of the shutter mechanism and doing a general inspection of the shielding to ensure its physical integrity.
A wipe test, also known as a leak test, around the area of the shielding must be performed at a minimum of every three (3) years or as specified in the license issued by the respective regulatory body.
Records of the operational safety checks and leak tests must be maintained by the site’s RSO or responsible party.

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Each device must be registered with the regulatory body for the state from which it is sold. These devices have strict design, safety, and dose rate requirements, and the design and devices cannot be altered or modified without first updating the sealed source device registration. Nuclear devices sold in the US by Berthold Technologies are registered with the Department of Environment & Conservation of the State of Tennessee.

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