Operating and maintaining the JWST cleanroom attached to JSC's chamber A during preparations for the OTIS cryogenic thermal vacuum test

Kelly A. Henderson-Nelson; Edwin W. Goldman; Joseph O. Ward; Jason E. Durner; Jason Brandon; Yingrui (Zao) Huang; Jonathan L. Homan

doi:10.1117/12.2641199

3 October 2022 Operating and maintaining the JWST cleanroom attached to JSC's chamber A during preparations for the OTIS cryogenic thermal vacuum test

Kelly A. Henderson-Nelson, Edwin W. Goldman, Joseph O. Ward, Jason E. Durner, Jason Brandon, Yingrui (Zao) Huang, Jonathan L. Homan

Author Affiliations +

Proceedings Volume 12224, Space Systems Contamination: Prediction, Control, and Performance 2022; 1222408 (2022) https://doi.org/10.1117/12.2641199
Event: SPIE Optical Engineering + Applications, 2022, San Diego, California, United States

Abstract

In order to maintain cleanliness during preparations for JWST’s OTIS (Optical Telescope Element-Integrated Science Instrument Module) Cryogenic Thermal Vacuum Test, a cleanroom was built that attached directly to the 60-year-old Chamber A. The cleanroom and chamber were outfitted with independent environmental control systems each providing ISO Class 71 air cleanliness. To maintain balanced, positive pressure in both the cleanroom and chamber volumes, a special control protocol was developed and successfully implemented. Dual back-up environmental control units (one each for the chamber and cleanroom) were installed just outside the building to provide environmental control redundancy due to a single source chilled water supply and weather threats. In addition, lack of a dedicated cleanroom airlock facilitating clean ingress and egress made it necessary to perform additional cleaning and packaging, as well as augment the uncontrolled truck lock space with small clean tents for pre-cleaning. Special procedures were developed to allow ingress of extra-large support equipment required for load testing of the cleanroom crane, installation of optical equipment in Chamber A and accommodation of the OTIS shipping container. A thorough bake-out and cleaning of Chamber A was also necessary to reduce volatiles from the shroud’s black thermal paint and to reduce particle fallout. Acrylic adhesive fracture discovered during early cryo-testing represented a significant challenge that was successfully mitigated prior to OTIS testing. A dedicated team of Contamination Control (CC) Technicians was specifically trained to clean support equipment and screen materials entering the cleanroom and chamber to ensure cleanliness and vacuum compatibility.

Conference Presentation

Citation Download Citation

Kelly A. Henderson-Nelson, Edwin W. Goldman, Joseph O. Ward, Jason E. Durner, Jason Brandon, Yingrui (Zao) Huang, and Jonathan L. Homan "Operating and maintaining the JWST cleanroom attached to JSC's chamber A during preparations for the OTIS cryogenic thermal vacuum test", Proc. SPIE 12224, Space Systems Contamination: Prediction, Control, and Performance 2022, 1222408 (3 October 2022); https://doi.org/10.1117/12.2641199

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available