Isolated power systems are an indispensable tool for hospitals, since they are used in operating rooms, intensive care units, cardiac catheterization laboratories, delivery rooms and critical medical areas.

Different hospital equipment uses this system for supplying electrical power without physical connection to ground, which reduces the risk of an electric shock and maintains the power supply during surgical procedures.

To prevent electric shocks and sparks that can cause a fire, isolated power systems should be reviewed annually. In the absence of an early detection of faults, the boards may not be able to protect patients from leakage currents and electric shocks that might cause their death.

Being an essential part of the electrical system of hospital facilities, the NFPA (National Fire Protection Association) establishes an annual review of the isolated power systems, since patient safety must be ensured through proper installations.


The inspection must be performed by a specialist and the verification must include technical documentation, tests, visual reports, and records according to RETIE (Technical Regulation of Electrical Installations).

¿For isolated power systems, what tests and records should be performed?


  1. Measure spurious or common node currents.
  2. Equipotentiality tests.
  3. Measure grounding resistance.

Records of tests performed:

  1. Corrosion level.
  2. Improvements to the grounding system if required.
  3. Document all changes since last inspection.
  4.  Resistance values.
  5. Condition of conductor joints and components.
  6. General condition of system conductors.
  7. Photographic record.

In IASS Ingeniería we have a technical team made up of professionals who specialize in the design and implementation of hospital electrical infrastructure projects, so if you want to perform the maintenance and annual review of your isolated power system, contact us!