[Jeff, Daniel]
The clean room smelled less of smoke, so I took some more particle counts at 2:50 PM, after ~150 minutes of the air purifier being on in B111A, to ensure we can do vacuum work in B111B and to see how well the air purifier is working. Other areas are also getting a lot better, so all of this improvement is very unlikely to be from the air purifier.
| B111A North small table | B111A Outside clean rooms west of north small table | B111B Control area | B111B Outside clean room by northeast shelves | B111B Inside clean room | B111 Antechamber | |
| 0.3 um | 0 | 46 | 88 | 59 | 0 | 1182 |
| 0.5 um | 0 | 9 | 42 | 28 | 0 | 283 |
| 1.0 um | 0 | 4 | 23 | 20 |
0 |
165 |
The particle counter in the B111B clean room read 14/0/0 on a first reading, so I more carefully turned it on by staying under the particle counter and it then read 0/0/0.
We installed the 2.75" 1550 nm AR Coated Viewport onto the Laser Filter Cavity (LFC) Output Vacuum Cube with an annealed copper gasket. The gasket had some discoloration/very light scratches on one face, but I think this is ok. We tightened the screws loosely, then tightly by hand, then by hand using the socket on the screws, then using the wrench with my hand near the bolt, then using the full length of the wrench, then using the torque wrench at 6 Nm, 7 Nm, 8 Nm, and finally at 9.6 Nm. 9.6 Nm was enough so that the flange appeared to be fully tightened. Special care was used to ensure we didn't touch the glass of the viewport flange. 14 Nm was used for the 2.75" blank flange and regular copper gasket.
We then pushed the LFC Output Vacuum Cube into place, secured it to the optics tables, and brought the LFC Input Vacuum Cube closer to the edge of the table so that we can more easily work on it. We tightened that cube to the table as well.