Putting safety in contextĀ
This 48-page document, āType of protection: intrinsic safety,ā is part of Pepperl+Fuchsā Explosion Protection Compendium. It covers intrinsic safety (IS) operating principles, circuits, verification, interconnection, installation, and protection types to use in fieldbuses. Itās here.
Three partsāand the entity
This seven-minute video, āIntrinsic safety: protection technique for hazardous locationsā by Hazcon Inc., covers basic principles, the three components of an IS system, circuit installation, and how the components work together to become an IS system, also known as the entity concept. Itās here.
Thorne & Derrick International
Greater safety understanding
This online article, āUnderstanding what s meant by intrinsically safe,ā defines hazardous areas, shows how to select pressure transducers and load cells for IS areas, describes installation and risk management, and answers frequently asked questions. Itās at https://www.omega.com/en-us/resources/understanding-what-is-meant-by-intrinsically-safe
Standards, codes and regional differences
This 52-minute webinar video, āIntroduction to intrinsic safetyā by Dave Malohn, staff engineer in the Energy and Power Technologies division at UL, teaches the definition of IS, different types of IS equipment, applicable standards and codes, differences between North American and international IS requirements, and fundamentals of designing IS equipment. Itās here.
Isolators and barriers
The online repository, āIntrinsic safety, barriers and isolators,ā provides links to IS articles about fundamentals, IS design, difference between IS and explosion proof, IS in hydrogen/oxygen mixtures, calculating IS loop approvals, subdivision of gases, cable parameters, IS junctions boxes, minimum ignitions curves, Zener diode barriers and others, Theyāre at- https://iceweb.eit.edu.au/equipment/intrinsic_safety_barriers_and_isolators.html
Engineering Institute of Technology
Verification, plant and layout
These two short videos, āIntrinsic safety verification made easyā and āHow to layout an IS circuitā by Barbara Vazquez-Isla, automation sales engineer at R. Stahl, show how to verify Ex I IS for hazardous applications with equipment from different manufacturers, as well as plan for IS circuits and layout IS cabinets. Theyāre here and here.
Design, install, inspect and maintain
This 20-page document, āA userās guide to intrinsic safetyā from MTL Instruments, Cooper Crouse-Hinds and Eaton, introduces its basic concepts and nomenclature, installation and inspection methods, system designs, and maintenance and repair proceduresāincluding a section on dust. It's here.
Practical principles
This five-minute video, "Principle of Intrinsic SafetyāExplanation of Intrinsic Safety Technology," covers dangerous gas mixtures, ignition curves, and how to limit them with Zener diodes and limiting circuits. Itās here.
Evolution of FISCO
This online article in Chemical Processing magazine, āThe intrinsically safe fieldbus has arrivedā by Dave Rizzo, explains the evolfieldbus intrinsically safe concept (FISCO), how it works with device couplers and power supplies, the split-architecture solution, entity parameters, and reducing downtime while easing maintenance. Itās here.Ā
(No) blast from the past
This online article, āSure-fire intrinsic safety,ā is the Resources Guide from 2017, and it consists of nine entries on understanding and implementing IS principles. Itās here.
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