Recommendation ITU-T L.107 describes the characteristics, construction and test methods for optical fibre cables to be installed in sewer ducts and drainpipes. The characteristics that a cable should have for an optical fibre to perform appropriately are described. Also, the test methods together with performance criteria are described for determining whether or not the cable has the required characteristics. The required conditions may differ according to the installation environment, thus detailed test conditions need to be agreed upon between the customer and manufacturer for the environment in which the cable is to be used. Recommended technical requirements are detailed by reference to [IEC 60794-3-40] on outdoor optical fibre cables for storm and sanitary sewers applications. Changes and additions to these requirements suitable to sewer cable application are recommended herein. Note that the Recommendation ITU-T L.78 was redesignated as ITU-T L.107 in February 2016.