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ISA-TR84.00.03-2002
Preface
This preface, as well as all footnotes and annexes, is included for information purposes and is not part of
ISA-TR84.00.03-2002.
This document has been prepared as part of the service of ISA
the Instrumentation, Systems, and
Automation Society
toward a goal of uniformity in the field of instrumentation. To be of real value, this
document should not be static but should be subject to periodic review. Toward this end, the Society
welcomes all comments and criticisms and asks that they be addressed to the Secretary, Standards and
Practices Board; ISA; 67 Alexander Drive; P. O. Box 12277; Research Triangle Park, NC 27709;
Telephone (919) 549-8411; Fax (919) 549-8288; E-mail: standards@isa.org.
The ISA Standards and Practices Department is aware of the growing need for attention to the metric
system of units in general, and the International System of Units (SI) in particular, in the preparation of
instrumentation standards. The Department is further aware of the benefits to USA users of ISA
standards of incorporating suitable references to the SI (and the metric system) in their business and
professional dealings with other countries. Toward this end, this Department will endeavor to introduce
SI-acceptable metric units in all new and revised standards, recommended practices, and technical
reports to the greatest extent possible.
Standard for Use of the International System of Units (SI): The
Modern Metric System
, published by the American Society for Testing & Materials as IEEE/ASTM SI 10-
97, and future revisions, will be the reference guide for definitions, symbols, abbreviations, and
conversion factors.
It is the policy of ISA to encourage and welcome the participation of all concerned individuals and
interests in the development of ISA standards, recommended practices, and technical reports.
Participation in the ISA standards-making process by an individual in no way constitutes endorsement by
the employer of that individual, of ISA, or of any of the standards, recommended practices, and technical
reports that ISA develops.
CAUTION — ISA ADHERES TO THE POLICY OF THE AMERICAN NATIONAL STANDARDS
INSTITUTE WITH REGARD TO PATENTS. IF ISA IS INFORMED OF AN EXISTING PATENT THAT IS
REQUIRED FOR USE OF THE TECHNICAL REPORT, IT WILL REQUIRE THE OWNER OF THE
PATENT TO EITHER GRANT A ROYALTY-FREE LICENSE FOR USE OF THE PATENT BY USERS
COMPLYING WITH THE TECHNICAL REPORT OR A LICENSE ON REASONABLE TERMS AND
CONDITIONS THAT ARE FREE FROM UNFAIR DISCRIMINATION.
EVEN IF ISA IS UNAWARE OF ANY PATENT COVERING THIS TECHNICAL REPORT, THE USER IS
CAUTIONED THAT IMPLEMENTATION OF THE TECHNICAL REPORT MAY REQUIRE USE OF
TECHNIQUES, PROCESSES, OR MATERIALS COVERED BY PATENT RIGHTS. ISA TAKES NO
POSITION ON THE EXISTENCE OR VALIDITY OF ANY PATENT RIGHTS THAT MAY BE INVOLVED
IN IMPLEMENTING THE TECHNICAL REPORT. ISA IS NOT RESPONSIBLE FOR IDENTIFYING ALL
PATENTS THAT MAY REQUIRE A LICENSE BEFORE IMPLEMENTATION OF THE TECHNICAL
REPORT OR FOR INVESTIGATING THE VALIDITY OR SCOPE OF ANY PATENTS BROUGHT TO
ITS ATTENTION. THE USER SHOULD CAREFULLY INVESTIGATE RELEVANT PATENTS BEFORE
USING THE TECHNICAL REPORT FOR THE USER’S INTENDED APPLICATION.
HOWEVER, ISA ASKS THAT ANYONE REVIEWING THIS TECHNICAL REPORT WHO IS AWARE OF
ANY PATENTS THAT MAY IMPACT IMPLEMENTATION OF THE TECHNICAL REPORT NOTIFY THE
ISA STANDARDS AND PRACTICES DEPARTMENT OF THE PATENT AND ITS OWNER.
ADDITIONALLY, THE USE OF THIS TECHNICAL REPORT MAY INVOLVE HAZARDOUS
MATERIALS, OPERATIONS OR EQUIPMENT. THE TECHNICAL REPORT CANNOT ANTICIPATE
ALL POSSIBLE APPLICATIONS OR ADDRESS ALL POSSIBLE SAFETY ISSUES ASSOCIATED