AS/NZS 60079.28:2016

This part of IEC 60079 specifies the requirements, testing and marking of equipment emitting optical radiation intended for use in explosive atmospheres. It also covers equipment located outside the explosive atmosphere or protected by a Type of Protection listed in IEC 60079-0, but which generates optical radiation that is intended to enter an explosive atmosphere. It covers Groups I, II and III, and EPLs Ga, Gb, Gc, Da, Db, Dc, Ma and Mb.This standard contains requirements for optical radiation in the wavelength range from380 nm to 10 µm. It covers the following ignition mechanisms:-Optical radiation is absorbed by surfaces or particles, causing them to heat up, and undercertain circumstances this may allow them to attain a temperature which will ignite asurrounding explosive atmosphere.-In rare special cases, direct laser induced breakdown of the gas at the focus of a strongbeam, producing plasma and a shock wave both eventually acting as ignition source.These processes can be supported by a solid material close to the breakdown point.NOTE 1 See a) and d) of the introduction.This standard does not cover ignition by ultraviolet radiation and by absorption of the radiation in the explosive mixture itself. Explosive absorbers or absorbers that contain their own oxidizer as well as catalytic absorbers are also outside the scope of this standard.This standard specifies requirements for equipment intended for use under atmospheric conditions.This standard supplements and modifies the general requirements of IEC 60079-0. Where arequirement of this standard conflicts with a requirement of IEC 60079-0, the requirement ofthis standard takes precedence.

Originated as AS/NZS 60079.28:2007.Second edition 2016. Originated as AS/NZS 60079.28:2007. Second edition 2016.