What are the limits of leakage currents in hospitals?

Electrical leakage current occurs as a result of current flowing through the protective grounding conductor of an electrical installation. It is common for such currents to occur and must be carefully monitored depending on both the installation’s safety and the presence of people in the area where such currents occur. 

In hospitals, leakage currents are controlled by isolated power systems, which use resistance and capacitance together to conduct current through very small circuits, resulting in a low leakage current amount.

Nevertheless, in some areas, such as ICUs and operating rooms, electrical safety is not guaranteed and is affected by a number of environmental factors. Medical equipment falls into this category, with its safety being determined by its operation, the surrounding conditions, the manner of use, and its maintenance.

For this reason, in order to ensure most safety conditions in hospitals, national and international standards must be followed; which require monitoring and preventative review activities that enable electrical risks to be minimized in high-risk areas such as operating rooms and operating theatres.

There are several standards for health care facilities, including the NFPA 99 (Health Care Facilities Code) which specifies different standards for health care facilities; in this statement is said that the voltage between the ground reference point and any exposed conductive surface should not exceed 20 mV in new construction, 500 mV in general care and residential areas and 40 mV in critical care areas.

In addition, there is a recommendation that the impedance between the common ground reference point and the ground of each receptacle should be less than 0.1 ohms in new construction and less than 0.2 in existing construction.

The proper application of these standards depends on the correct installation and maintenance of isolated power systems within hospitals, as they are vital for controlling leakage currents limits inside installations.

At IASS ingeniería, our specialty is isolated power systems. And we are authorized distributors for ‌ ‌ PG ‌ ‌ ‌LifeLink‌. We are known for our quality, experience, and rigor in implementing hospital electrical systems that conform to the NFPA 99 and RETIE standards. Please contact us!