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Click to read - THE TRUTH ABOUT OS1 (NOW OS1A) AND OS2


There continues to be a great deal of confusion about the purpose, and meaning, of the cabled optical fibre Categories OS1 and OS2. This confusion exists at all levels of the industry and affects, in equal measure, the suppliers of optical fibre and optical fibre cable, distributors, installers, customer and their consultants.

This has now been exacerbated by the replacement of OS1 by OS1a in the latest editions of the ISO/IEC 11801-x and EN 50173-x standards for generic cabling.

NOTE:     The above standards are available as BS ISO/IEC 11801-x:2017 and BS EN 50173-x:2018

This White Paper replaces the FIA White Paper entitled “The Truth About OS1 and OS2” last revised in October 2010 and explains the subtle differences between the European specifications of OS1a/OS2 and their international counterparts in ISO/IEC.

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