This part of IEC 60794 sets forth technical requirements and characteristics of single-mode optical fibre cables for duct and direct buried installation. This specification includes functional mechanical, environmental and optical requirements, recommended features and test methods for assessing the product against the stated requirements. The specified test methods, where applicable, are those referenced in IEC 60794-1-1 and described in detail in IEC 60794-1-2. The requirements of this specification supplement those of IEC 60794-3 and IEC 60794-3-10 Multimode fibre requirements are not addressed in this standard; see IEC 60794-3-12.