Texas provided the following information via email:
On August 7, 2012, the licensee notified the Agency that on August 6, 2012, the shutter on a Ronan Model SA-1 fixed nuclear gauge, containing 100 millicuries of cesium-137, at its facility in Longview, Texas, was found to be stuck in the open position. During routine inspection and operation checks in March 2012, the licensee observed that the shutter was difficult to operate. The licensee's maintenance staff had made several unsuccessful attempts to fix the problem. On August 6th, the maintenance staff was going to make another attempt but the shutter was completed stuck and could not be freed. The shutter on this gauge is in the open position during normal operation so there was no increased risk to any individual and there have been no exposures. The licensee has contacted the manufacturer to schedule repairs, has notified employees of the gauge's status, and has implemented administrative controls to restrict access until repairs are completed. More information will be provided as it is obtained, per SA-300.
Source/Source Holder information:
Model: Ronan SA-1
Cesium-137 -- 100 millicuries
Serial #: JJ590
Texas Incident #: I-8973