IEC 60296 specifies key quality properties for unused mineral insulating oils, generally including dielectric strength, moisture content limits, acidity, dielectric dissipation factor, resistivity, density, viscosity, flash point, and oxidation stability. It also addresses inhibitor status for inhibited oils and quality aspects related to appearance and potential corrosive behavior. The standard provides a baseline so utilities can procure oil with predictable performance and consistent test results. Exact limit values depend on the oil category and edition referenced in the procurement specification.