DOCUMENT RESUME ED 384 356 IR 055 533 AUTHOR Van Bogart, John W. C. TITLE Magnetic Tape Storage and Handling:-A Guide for Libraries and Archives. INSTITUTION Commission on Preservation and Access, Washington, DC.; National Media Lab., St. Paul, MN. REPORT NO ISBN-1-887334-40-8 PUB DATE Jun 95 NOTE 42p. AVAILABLE FROMCommission on Preservation and Access, 1400 16th St., N.W., Suite 740, Washington, DC 20036-2217 ($10; orders must be prepaid). PUB TYPE Guides Non-Classroom Use (055) EDRS PRICE MF01/PCO2 Plus Postage. DESCRIPTORS *Audiotape Cassettes; Costs; Equipment Maintenance; Equipment Standards; Equipment Storage; Guides; Library Facilities; *Magnetic Tapes; *Preservation; Problems; Repair; *Videotape Cassettes IDENTIFIERS *Library Materials Conservation; Restoration ABSTRACT This document provides a guide on how to properly store and care for magnetic media to maximize their life expectancies. An introduction compares magnetic media to paper and film and outlines the scope of the report. The second section discusses things that can go wrong with magnetic media. Binder degradation, magnetic particle instabilities, substrate deformation, magnetic tape recorders; and format issues are highlighted in this section. The third and fourth sections cover preventing information loss with multiple tape copies, costs, and how long magnetic media will last. In the fifth section, care and handling, storage conditions and standards, and refreshing of tapes are described for preventing magnetic tape from degrading prematurely. An appendix provides the Ampex Guide to the Care and Handling of Magnetic Tape, an estimation of life expectancies, sources for furtherreading, resources for transfer and restoration of video and audio tape, and a glossary. (AEF) *********************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. *********************************************************************** U.S. DEPARTMENT Of EDUCATOR Oftce of EOue litrOolir Realism'. andPnoymyynyont EDUCATIONAL RESOURCJS INFORMATION CENTER IERV: Ms document hes beenreproduced se reypyO from In* perion or Ofganttatton ortokultirg rl 0 Woof cturnpos nowt beammad* to .mprov retproduckOn Quality P001160! ybeve of toornions statOIN* deCo- mint Po not nCssenly repr1141n1ottle,a1 OE RI posdkon or pokey Magnetic Tape Storage and Handling A Guide for Libraries andArchives L ALNATIONAL MEDIA LAB "PERMISSION TO REPRODUCE THIS MATERIAL HAS BEEN GRANTED BY June 1995 M.K. Sitts TO THE EDUCATIONAL RESOURCES BEST COPY AVAILABLE INFORMATION CENTER (ERIC)." The Commission on Preservation and Access is a private, nonprofit organization acting on behalf of the nations libraries. archives. and universities to develop and encourage collaborative strategies for preserving and providing access to the accumulated human record. 2 Additional copies are available for 510.00 from the Commission on Preservation and Access. 1400 16th St.. NW. Ste. 740. \X'ashington, DC 20036-2217. Orders must be prepaid. with checks in U.S. funds made payable to The Commission on Preservation and Access." This paper has been submitted to the ERIC Clearinghouse on Information Resources. 0 The paper in thispublication meets the minimum requirements of the American National Standard for Information Sciences-Permanence of Paper for Printed Library Materials ANSI Z39.48-I992. ISBN 1-887334-40-8 No part of this publication may be reproduced or transcribed in any form without permission of the publisher. Requests for reproduction for noncommercial purposes. including educational advancement, private study, or research will be granted. Full credit must be given to the author. the Commiy:ion on Preservation and Access, and the National Media Laboratory. Sale or use for profit of any part of this document is prohibited by law. Magnetic Tape Storage and Handling A Guide for Libraries and Archives by Dr. John W. C. Van Bogart Principal Investigator. Media Stability Studies National Media Laboratory June 1995 Published by The Commission on Preservation and Access 1.100 10th Street. NW. Suite 740 Washington. DC 20036-221- and National Media Laboratory Building X35 -1N -1- St. Paul, NlN ii1-14-1000 This report Is a ioint protect of the Commission on Preservation and Access and the National Media Laboratory, developed within the Commission's Preservation Science Research initiative. The initiative encourage,. new techniques and technologies to manage chemical deterioration in library and archival o )llecttons and to extend then useful lite. 4 L ALNATIONAL MEDIA LAB Building 235-1N-17 St. Paul, MN 55144-1000 'the National Media Lab I NMI.) is an industry resource supponing the U.S. Government in the evaluation. development and deployment of advance storage media and systems. The NMI. endeavors to provide a broad perspective of current progress in storage issues, both from a commercial and government perspective The NNII. accomplishes its mission by acting: As a CONSULTANT to the.S. Government. specializing in data storage and access requirements. assessing evolving technologies. determining applicability of currently available technologies to recording programs. and influencing commercial recording systems standards to accommodate Government requirements. As a RESEARCH AND DEVELOPMENT FACILITY which includes tech- nology assessment and evaluation capabilities. measurements and testing laboratories, and prototype product development capabilities. This research facilityisdistributedacrossindustry.university and Government laboratories. Asa TECHNICAL SERVICE organization.providing user supportat operational sites. field monitoring. rapid crisis response. and the transfer of technology and information. As an ADMINISTRATI \ T. AGENT in programs which require both broadly- basedindustrial and academic resources and coordinationacross Government. industry boundaries. More information about the N \IL and its accomplishments is available on the Internet via the Vbrld Wide Web. 1bu can access the NML Home Page at the following URL: http:www.nall.org 5 Table of Contents Preface Author's Acknowledgements 1.Introduction 1 1.1 Magnetic Media Compared to Paper and Film 1 1.2 The Scope of the Report 1 2. What Can Go Wrong with Magnetic Media? 2 Figure I. Diagram of. a Tape Reel Figure 2. Cross Section cy'a .1lag,netic Tape 3 2.1 Binder Degradation 3 Lubricant Loss 4 2.2Magnetic Particle Instabilities 5 2.3Substrate Deformation 6 2.4Format Issues 7 Helical versus Longitudinal Scan Recording Figure 3. Helical Scan Recording Figure 4. Types Mistracking for Helical Scan Recording 8 Figure 5. Longitudinal Recording 8 Analog versus Digital Storage 8 2.5 Magnetic Tape Recorders 3.Preventing Information Loss: Multiple Tape Copies 10 4.Life Expectancy: How Long Will Magnetic Media Last? 11 4.1Tape Costs and Longevity 11 4.2 Practical Life Expectancies 11 5. How Can You Prevent Magnetic Tape from Degrading Prematurely? 12 5.1 Care and Handling 13 Frequent ACCey, Transportation of Nlagnetic Tape 1 5.2Storage Conditions and Standards 14 Temperature and Relative Humidity 14 Figure (). Temperature and Humidity Omditions and Risk of Hydrolysis 15 Variations in Temperature and Humidity 15 Figure 7. Bad Tape Wind &amp les 16 Dust and Debris 16 Figure 8. Size of Tape Debris Relative to the Tape/Head Spacing 16 Corrosive Gases 17 Storage Recommendations 17 Table 1. Current Recommendations jOr Magnetic Tape Storage 17 Table 2. Key Features of Access and Archival Storage cy'Magnetic Tape 18 Removal of Magnetic Tapes from Archival Storage 19 Table 3. Acclimation Times for Magnetic Media Removed from Archilyd Storage 19 5.3 Refreshing of Tapes 19 Appendix 21 Ampex Guide to the Care and Handling of Magnetic Tape 23 Recommended practices 23 Figure 9. Tape Debris 4 Tape handling 25 Rotary Head Recorders 26 Estimation of Magnetic Tape Life Expectancies (LEs) 28 Figure 10. Life Expectancies for a Hi Grade VHS Tape '8 Further Reading 29 Resources for Transfer and Restoration of Video and Audio Tape 29 Glossary 30 Preface This report from the National Media Laboratory (NNIL) helps clarify long-term storage requirements for magnetic media. The information is derived from the industry's accu- mulated knowledge base. plus media stability studies and operations support activities conducted by the NMI. for the l'. S. Government advanced data recording community. Clearly. the purpose and scope of long-term magnetic media storage issues for libraries and archives are different from those of many Government operations. but thebasics remain the same. The report focuses on how to properly store and care for magnetic media to maximize their life expectancies. However, it provides more than a how-to guide. The author includes technical explanations for the rationale behind recommended procedures. written specifically for librarians, historians, records managers. archivists, and others who do not have a significant background in recording technology.In addition. the report is useful for decision-making and cost-benefit analyses for managers and administrators who have responsibility for the long-term preservation of information stored on magnetic media. Author's .cknowledgements The author wishes to thank Devon' Molitor. Pestctzel. Chris Ward. and Jim Druzik for their dis cerning comments, notable suggestions. and assistance in preparing this manuscript. 1. Introduction The use of magnetic media to record and store numeric and textual information. sound. motion. and still images has presented