Why is it crucial to perform leakage current tests on therapeutic equipment?

Performing leakage current tests on therapeutic equipment is crucial because these devices often come into direct contact with patients and can deliver electrical energy for therapeutic purposes. Leakage current refers to the small, unintended electrical current that can flow from the device's chassis or applied parts to ground or to the patient. Even small amounts of leakage current can pose a significant electrical shock hazard, particularly for vulnerable patients or those with invasive devices. For example, a patient with a central venous catheter is more susceptible to microshock, which is a dangerous electrical shock that can occur when a small current passes directly through the heart. Leakage current tests are performed to ensure that the device's leakage current remains within safe limits, as defined by standards like IEC 60601. These tests involve measuring the current that flows under various conditions, such as normal operating conditions and single-fault conditions (e.g., a failure of the device's insulation). If the leakage current exceeds the allowable limits, it indicates a potential electrical safety hazard that needs to be addressed before the device is used on patients. Regular leakage current testing is an essential component of a comprehensive electrical safety program for medical equipment, helping to protect patients and healthcare personnel from electrical shock and ensuring the safe and effective use of therapeutic devices.