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Evaluation of Systems for Intrinsic Safety

  • Ernest C. Magison
Chapter

Abstract

Evaluation of a system, i.e., equipment and associated wiring, to determine whether it is intrinsically safe in accordance with the requirements of ISA Recommended Practice RP12.2, is not, and cannot be, a “cookbook” procedure. ISA RP12.2 adequately states the essential energy limitations and specifies the considerations of failure against which to judge the system. However, it is not practical to list all possible specific constructional features which would render a particular mode of failure highly improbable or “for all practical purposes” impossible. The requirements of RP12.2 must be applied to a particular system with judgment. This judgment must be based on knowledge of the technology underlying the specific requirements of RP12.2. This is emphasized in RP12.2, paragraph 2.4:

“This Recommended Practice is intended to promote uniformity among specialists. It is intended that it be applied only by those who have carefully studied the subject. This Recommended Practice is not an instruction manual for untrained persons.”

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References

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Copyright information

© Springer Science+Business Media New York 1966

Authors and Affiliations

  • Ernest C. Magison
    • 1
  1. 1.Honeywell Inc.Fort WashingtonUSA

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