Abstract: An operability testing apparatus used in conjunction with an electrical testing apparatus to perform live-dead-live tests consists of: a power source; a voltage source coupled to the power source with the voltage source being configured to provide an AC voltage output and/or a DC voltage output; and one or more visual indicators. The visual indicator(s) are configured to indicate operability for electrical testing equipment such as voltmeters and the like. The probes or leads of electrical testing equipment are inserted into apertures in the apparatus. The apparatus provides an output, allowing a determination to be made as to the operability of the electrical testing equipment. Then, the test leads or probes are applied to the subject electrical circuit or equipment to ensure that the subject electrical circuit or equipment is de-energized.