Standard specifications for insulating oil used in power transformers, instrument transformers, bushings, bulk oil circuit breakers, oil circuit reclosers, and switches were provided. The specifications are divided into Class A and Class B depending on the requirement for kinematic viscosity at -40 degrees C. A Class S oil is also introduced for oil circuit breakers. The standards were prepared by the Technical Committee on Transformer and Switch Oils under the jurisdiction of the Steering Committee on Electrical Engineering, and has been formally approved by these committees. It has been also approved as a National Standard of Canada by the Standards Council of Canada. The document provides a list of reference publications, describes the samples and test procedures, properties and delivery requirements. 1 tab.