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4.0 Hazardous Locations
FOS-01 Operation Manual
Page 6 of 17
4.0 Hazardous Locations
The Fiber Optic Switch meets the requirements of European Parliament Directive 94/9/EC,
Equipment and
protective systems Intended for use in potentially explosive atmospheres (ATEX Directive) and
IEC 60079-28
(Explosive atmosphere - Protection of equipment and transmission systems using optical radiation) when
used in conjunction with the Fiber Optic Interface FOI-01-221.
According to ATEX Directive, the Fiber Optic Switch is classified as Simple Apparatus "Ex op is" for the
following reasons:
- The device is entirely passive and non-electrical.
- Light energy produced by the Fiber Optic Interface meets the requirements for Ex Op is (inherently safe
optical radiation) per IEC 60079-28 and ANSI/ISA 60079-28.
The device being a "Simple Apparatus" shall not bear the CE mark according to the ATEX directive.
Therefore, the Fiber Optic Switch can be safely installed and operated in any type of hazardous area:
- ATEX Equipment Group I (Mines); All Categories (M1 and M2); All Gas and Dust Environments
- ATEX Equipment Group II; All Categories (1, 2 and 3); All Gas and Dust Environments
According to NEC 504.2, the Fiber Optic Switch is classified as Simple Apparatus for the following reasons:
- The device is entirely passive and non-electrical.
- The device does not dissipate any power that can increase its surface temperature over ambient.
- NEC 500 Class I (Gas and Vapor), Divisions 1 and 2, Group. A, B, C, D, Temp. T6
- NEC 500 Class II (Dust), Divisions 1 and 2, Group E, F, G Temp. T6
- NEC 500 Class III (Fibers or Flyings), Divisions 1 and 2
- NEC 505 Zones (Gas and Vapor): Zones 0, 1, 2, 20, 21, 22
According to NEC 504.4 the Fiber Optic Switch being a "Simple Apparatus" does not have to be listed.