What is the key purpose of conducting an air test on rubber gloves?

Conducting an air test on rubber gloves primarily serves to confirm their insulating properties. This process involves inflating the gloves with air to check for any leaks or defects that could compromise their ability to provide electrical insulation. Ensuring that the gloves retain air without any loss indicates their integrity and effectiveness in protecting the wearer against electrical hazards.

While other options like checking for physical damage and ensuring a proper fit are certainly important aspects of using rubber gloves, they do not specifically address the core function of testing the gloves' insulating capabilities, which is critical for safety in electrical work.