This was the second test of the day on October 4th, recorded in Oak Ridge Tennessee. This siren is part of the system for the national lab and is located behind the post office in downtown Oak Ridge. The sirens test on the first Wednesday of the month at noon in three minutes of alert and are used to warn of accidents at the Y-12 facility. This system was installed sometime around 2012 and replaced the old system of AL-6000R and AL-7200 sirens whereas the ETTP kept the older sirens. The system is mostly comprised of T-121s, however there are also a few T-135 DC sirens and some I-Force STI-3200s around the national lab. I hope to record one of the T-135s soon, but I have to say that the T-121 was quite potent. Here is the aforementioned video:
https://www.youtube.com/watch?v=Go2mu9w-euE