This part of IEC 61753 contains the minimum test and measurement requirements and severities which a sealed fibre optic closure must meet in order to be categorised as meeting the IEC standard for Category A - Aerial, as defined in Annex A of IEC 61753-1. Pressure compensating closures are not covered by this standard. The closures are used in feeder and wide area networks and become increasingly important when expanding fibre-to-the-home-networks. The standard contains the minimum requirements, the details and the severities for 25 different tests of the IEC 61300 series. Thus, the standard provides manufacturers and users with investment security and test laboratories and manufacturers with detailed information on testing. The standard is one of three similar standards which differ by installation environment and, therewith, by detail and severity: DIN EN 61753-111-7 - Aerial DIN EN 61753-111-8 - Ground DIN EN 61753-111-9 - Subterranean The responsible Committee is Subcommittee UK 412.2 "Komponenten für Kommunikationskabelanlagen" ("Components for communication cabling systems") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.