CLEAN ROOM TECHNOLOGY - Welcome to CaltechAUTHORS - CaltechAUTHORS
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CLEAN ROOM TECHNOLOGY Useller
Transcript of CLEAN ROOM TECHNOLOGY - Welcome to CaltechAUTHORS - CaltechAUTHORS
CLEAN ROOM TECHNOLOGY
Useller
NASA SP-5074
EAN ROOM NOLOGY
Bv James W: Useller
Lewis Research Center, Cleveland, Ohio
Th 1 ec no ogy Utihzatron D~v~s~o?z
OFFICE OF TECHNOLOGY UTILIZATION 1969 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
Washington, D.C.
For Sale by the Superintendent of Documents,
U.S. Government Printing Office, Washington, D.C. 20402
Price 35 cents
Library of Congress Catalog Card Number 75402376
FOREWORD
The emphasis on improving component reliability in the United States Space Program has generated an expanding number of facilities throughout NASA and its supporting contractors to control contamination. NASA has reported many hardware failures attributable to contamination. Although the clean room is only one of several elements in a contamination control plan, it is a vital part. Developing the techniques for contamination control requires an increasing number of trained technicians each year. The literature related to clean rooms abounds in information from a wide variety of sources and diverse technical publications, but a comprehensive compilation for use in training clean room technicians is not easily found.
This publication evolved from lectures presented to acquaint technicians and their supervisors with the characteristics and operation of a clean room. The material has been gathered not only from published data, but also from discussions with clean room operators and recognized authorities in contami- nation control technology. This is one of a series of publications issued to make technological information of potential value to many industries generally available.
CONTENTS
Page BACKGROUND INFORMATION. ....................................
Historical Background. .............................................. Needfor CleanRooms ............................................... Nature and Origin of Contamination ...................................
CLEAN ROOMS .....................................................
Controlling Contamination With a Clean Room ......................... Air Cleanliness Classes and Standards .................................. Conventional Flow Clean Rooms. ..................................... Laminar Flow Clean Rooms. ......................................... Comparison of Clean Room Types. ................................... Laminar Flow Work Stations. ........................................
CLEAN ROOM ENVIRONMENT .. : .................................. CleanRoomMonitoring ..............................................
Pressure Monitoring. ................................................ Temperature Distribution. ........................................... Humidity Measurements. ............................................ Particulate Monitoring. .............................................. SelectionofSample ..................................................
Manual Counting Technique .......................................... Samplingprocedure ................................................
Preparation of microscope. ......................................... Countingparticles .................................................
Calculations ......................................................
Precisionandaccuracy .............................................
Automatic Counting Techniques ....................................... Light transmission method .......................................... Electrical aerosol method. .......................................... Lightscatteringmethod ............................................
Operating cost comparison. ......................................... EffectofStaticCharge ...............................................
Liquid-Borne Contaminants. ......................................... Monitoring Questionnaire. ............................................
CLEAN ROOM OPERATION ......................................... Factors Affecting Clean Room Operation. .............................. Facility Design Criteria. ............................................. Selection of Clean Room Equipment. .................................. Clean Room Personnel Garments. ..................................... CleanRoomMaintenance ............................................
Clean Room Certification .............................................
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CLEAN ROOM PERSONNEL. ............
Selection of Clean Room Operators. ........ Personnel Control Procedures. ............. Training and Certification of Operators ......
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CLEANING TECHNIQUES ................ Pure Water ..............................
Precision Cleaning Methods ................ Evaluating Cleaning Methods. .............
Water break test. ...................... Atomizer test. ......................... Contamination monitoring systems. ......
Clean Room Packaging .................... Packaging materials. ................... Precision packaging checklist. ...........
GLOSSARY OF CLEAN ROOM TERMS
BIBLIOGRAPHY
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