Reports until 18:17, Thursday 10 November 2011
H1 PEM
thomas.vo@LIGO.ORG - posted 18:17, Thursday 10 November 2011 (1708)
Analysis of 2011-11-10 Dust Monitors 3, 4, &11
Attached are the trend plots for the three dust cameras 3, 4, & 11.  Dust Monitor 3 and 4 were located in the clean room over the ISI/Quad Test stand. Dust Monitor 11 was located between the aforementioned clean room and the clean room over HAM 12 where ICC were using drills throughout the day.  The plots are intended to look for any high dust counts that could connect monitor 11 to 3 and 4.  This would indicate the effectiveness of the anti-contamination mechanisms which are put in place to prevent particles from affecting the ITM, such as the HEPA filters over the ISI and the filter on the various drills which are used for ICC.

Preliminary Analysis:
Dust Monitor 11 is located outside of the clean rooms so it is subject to high amounts of particulates leading to its count remaining high through most of the day but there were two relatively large spikes at approximately 18:00 and 23:00.  The first large spike could possibly be when the drills first started combined with a large amount of people walking past the monitor.

Dust Monitor 3 is relatively low in the morning but picks up around 19:00, attributed maybe to normal activities.  The largest dust counts come towards the end of the day but does not seems to be caused by the drilling as indicated by Dust Monitor 11. 

Dust Monitor 4 shows very high dust counts at 19:00 also as well as 20:00.  To be noted, at approximately 23:15 Dust Monitor was disconnected and adjusted so readings during this time are mostly likely invalid.

All in all, judging from the graphs shown, it seems like the the amount of particles that are showing up between the two clean rooms are not correlated to the high dust counts that are indicated by the monitors 3 and 4 in the ISI clean room throughout the day. 

On Monday, the ICC team plans to continue and it'd be a good chance to re-apply a similar analysis.

Non-image files attached to this report