[Kimura and Yasui]

 We installed an interlock circuit in the #-39 pumping unit at X-end on Apr. 24..
After installation, we confirmed that the interlock circuit works in the event of a power failure and that the shutoff valve between the dry pump and the TMP is closed.
After this operational test, the gate valve between the pumping unit and the duct was opened and the TMP of the #-39 pumping unit started pumping.

 We also installed blue and red double-sided magnetic sheets to indicate operating status of vacuum pumps.
The blue side of the magnetic sheet indicates " operation", while the red side indicates " shutdown".