Open-beaker oxidative aging methods have been used for many years in laboratories of oil companies, electrical equipment manufacturers, and electric utility companies interested in the stability of electrical insulating oils under oxidative conditions. They are particularly useful as a check on the continuity of production and shipment of insulating oils. They are also useful as process and product checks for applicable type oils.

Specification limits for oils subjected to open-beaker oxidative aging by this method are established by agreement between individual producers and consumers of applicable type oils. These properties of the oil involved in specification limits for aging stability may be measured after the oxidative aging (and sometimes before aging) by appropriate test methods such as Test Method D 924, Test Method D 1169, and Test Method D 664.

1.1 This test method describes two procedures for subjecting electrical insulating oils to oxidative aging:

1.1.1 Procedure A , without a metal catalyst, and

1.1.2 Procedure B , with a metal catalyst.

1.2 This test method is applicable to oils used as impregnating or pressure media in electrical power transmission cables if less than 10% of the oil evaporates during the aging procedures. It applies and is generally useful primarily in the evaluation and quality control of unused oils, either inhibited or uninhibited.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.