The T2 plug block was replaced and the M9 and M20 beam blockers were tested.  The plug block did not interfere with the travel of the beam blockers.  There was no change in the T2 vacuum during BB actuation.

Initially there was some confusion about how to actuate the beam blockers.  The following was learned:

M9BB:
- The M9 beam blocker is no longer part of a safety system because there are separate blockers for the M9A and M9B channels
- The M9 beam blocker does not need to be 'enabled' before actuation
- The M9 beam blocker can be actuated from the M9B ASU panel located on the B2 level
- The M9 beam blocker cannot be actuated from the control room.

M20BB:
- There are no additional blockers in the M20 beam line, so the M20BB functions as a safety system and must be lowered before the M20 area can be accessed
- The M20BB must be 'enabled' by controls before it can be actuated
- The M20BB can be actuated from the control room or the M20 ASU on the B2 level