1. The Coudé Lab Environment Boulder 18 March 2009

2. The Coudé Lab

3. Air Curtain Interface

4. Instrument Foundations

6. Air Curtain Interface

7. Dust Control Requirements 0.002 %/hr ≈ 264 ppm per 24 hrs Figure 15. The figure shows the effects of dust accumulation on the primary mirror after one day and one week, assuming the UKIRT accumulation rate of 0.002 percent per hour. [TN-0013] … we can tolerate about … 0.3 percent total coverage…we will exceed the stray- light budget after only 132 hours (about five days). [TN-0083] Photosphere: The scattered light from telescope and instrumentation from angles > 10 arcsec shall be 1% or less.

8. Cleanrooms Class # 0.5 mm particles per ft3 # 5.0 mm particles per ft3 air changes per hour ceiling filter coverage (%) air velocity (fpm) max. vibration (min/s) temp. tolerance RH tolerance approx. capital cost per ft2 office12-18?$10 100,000 65018-3010$50 10,000 6540-603010±3.0°F±5%$200-250 1,000 6.5150-3005030-50±2.0°F±5%$350-400 100 0.65400-54080-10075-90500±1.0°F±5%~$1200 10 0.065400-54010075-90250±0.5°F±3%~$3500 110.0065540-60010090-100250±0.3°F±2%~$10,000+ 0.5 0.0033540-600100100-110125±0.1°F±1%~$25,000+ Cleanrooms fall under the following FED-STD-209E classifications: Note: Dunn environment approximates Class 100,000 (ISO 7) with existing filtration in use

9. The Downflow Concept

10. Environmental Rooms Clean Room – has a controlled level of contamination that is specified by the number of particles per cubic meter at a specified particle size, but it also implies many other parameters. Environmental Room - temperature and/or humidity level is controlled at a single set condition within specified tolerances regardless of activity in the room. In any case - tight temperature control requires flow that is free of recirculation zones.

11. The Coudé Lab END

12. from “The Harris Guide to Environmental Room Design” Design Parameters Temperature and Velocity (0.5 m/s and 20 or 21 or 22  C)Design set-point (0.5 m/s and 20 or 21 or 22  C) (0.25  C)Temperature Uniformity @ work surface (0.25  C) (0.5  C)Temperature Gradient through room (0.5  C) (0.5 m/s @ optics)Velocity (0.5 m/s @ optics) Heat Loads (sensible & latent) Design allowance (lights, ventilation, instruments, equipment, etc.) (people, laptops, equipment?)Vagrant Loads (people, laptops, equipment?) Humidity (45%±5%)35-50% for comfort, 45% for ESD (45%±5%) Low to prevent hygroscopic adhesion of dust Dust Control Filtration vs. cleaning Contamination control (personnel, construction materials, etc.) Pressure Control (positive pressure) Service Access (access to filters, etc.) Vibration (fans, equipment locations)

13. CROSS FLOW mechanical packaging Air Handling Unit Return Air Supply Air

14. CROSS FLOW results

15. CROSS FLOW boundary conditions SUPPLY RETURN Air properties for 3000-m 16ea – 4’x4’ openings supplying 4 m 3 /s @18˚C 16ea – 4’x4’ openings for return @ P=0 Pa Thermal properties set up, but never run