THOMAS JEFFERSON NATIONAL ACCELERATOR
The U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility in Newport News, Virginia, is al electron accelerator basic-physics research facility. The device that captures the residual energy of the beam after use is housed in a nitrogen-blanketed, five thousand cubic foot enclosure. The original vent allowed air to back-draft, increasing the O2 concentration above acceptable levels. A few weeks ago the lab installed a 360 Siphon. The following is a recent comment by a senior engineer.
“Gents, Last week, after the electricians sealed up the electric box on the N2 pump and facilities installed the new vent cap on the stack, I made a couple measurements at the dump vent stack for flow and O2.
The flow was significantly higher than it had been in the past (there was a mild breeze blowing, and the effect of the gusts of wind could clearly be seen, drawing the gas out of the stack). The manufacturuer of the cap says that even a 1 mph wind will establish a positive draft on the stack.
The O2 level is at the lower limit of what the meter could read (essentially 0% oxygen). This is a great improvement, and indicates that we are getting an effective purge (better than the design goal). I want to confirm this with a measuremenet from inside the hall.
Thanks to everyone for your support.”