The Centers for Medicare & Medicaid Services (CMS) mandates adherence to NFPA 99, ensuring that healthcare facilities meet these rigorous standards. NFPA 99 establishes criteria for healthcare services based on the risk to patients, staff, and visitors, aiming to minimize fire, explosion, and electricity hazards. It sets minimum requirements for the inspection, testing, maintenance, performance, and safe practices of essential electrical systems (EES).

An overview of essential electrical systems in NFPA 99

NFPA 99, published by the National Fire Protection Association, establishes minimum criteria for various systems and equipment in healthcare facilities. Specifically, Chapter 6.7 of NFPA 99 focuses on the EES, detailing the performance, maintenance, and testing requirements to ensure a reliable and continuous power supply. These systems are crucial for patient safety, operational continuity, and compliance with regulatory standards, as they provide power to critical areas such as operating rooms, intensive care units, and emergency departments.

The code outlines specific requirements for installing and testing generators and other critical electrical components. By adhering to these standards, healthcare facilities can mitigate the risk of power failures, ensuring the safety and well-being of patients, staff, and visitors while also maintaining compliance with federal, state, and local regulations.

Normal power vs. on-site power

Normal power* refers to the primary electrical supply provided by a healthcare facility’s local utility company. It is the standard power source for all nonessential and essential electrical loads under normal operating conditions.

Characteristics of normal power include:

  • While generally reliable, normal power can be interrupted by utility failures, natural disasters, or other unforeseen events.
  • It is usually delivered through the local electrical grid, which is susceptible.
  • Healthcare facilities rely on this power source for day-to-day operations, including lighting, HVAC systems, and noncritical equipment.

(* It is important to note that neither the NFPA 70®, National Electrical Code®, nor NFPA 99, Health Care Facilities Code, defines a “normal” system explicitly. Generally, the normal system encompasses all elements not required to be part of the EES. The critical requirement is that there must always be at least two independent power sources, one of which must be on-site.)

On-site power refers to backup power systems, such as generators, installed within the healthcare facility premises to provide an alternate power source when normal power fails.

Characteristics of on-site power include:

  • On-site power systems are designed to automatically activate and supply power to the EES within seconds of a normal power system outage.
  • These systems operate independently of the local utility grid, ensuring continuity during external power disruptions.
  • It typically includes diesel or natural gas generators, transfer switches, and sometimes battery backup systems to ensure immediate power availability.
  • On-site power systems must meet specific standards and regulations, such as those outlined in NFPA 99, to ensure they can reliably support life safety and critical loads in healthcare facilities.

The branches of an essential electrical system

An EES in healthcare facilities is meticulously designed to ensure continuous power supply to vital areas and equipment during normal operations and emergencies. To achieve this, the EES is divided into three distinct branches: the life safety branch, the critical branch, and the equipment branch. Each branch has specific functions and requirements to maintain the highest level of reliability and safety.

  • Life safety branch. The life safety branch provides power to systems that ensure the safety of occupants during an emergency, such as emergency lighting, fire detection, alarm systems, communication systems, and exit signs to facilitate safe evacuation. This branch must receive power restoration within 10 seconds of a power outage.
  • Critical branch. The critical branch supplies power to areas and equipment for patient care and treatment. These include critical care areas, operating rooms, intensive care units, life-support systems, monitoring systems, and other medical equipment and devices crucial to patient care. Like the life safety branch, the critical branch requires power restoration within 10 seconds.
  • Equipment branch. The equipment branch supplies power to equipment essential for the healthcare facility’s operational efficiency but does not directly affect patient care or safety. This branch includes components such as HVAC systems, sterilization equipment, and other essential operational equipment that support the hospital’s infrastructure. Power restoration for the equipment branch can be delayed by as much as a few minutes after restoring the critical and life safety branches.

On-site power source requirements

NFPA 99 sets strict standards for generators within healthcare facilities. These standards include needing multiple independent power sources, proper sizing and reliability of on-site generators, and careful placement and protection. The code also covers coordinating overcurrent protective devices (OCPD), ground-fault protection, regular maintenance and testing, transfer switch requirements, and maintaining an adequate fuel supply.

Additionally, keeping detailed documentation and compliance records is crucial to prove adherence to these standards. By following NFPA 99 requirements, healthcare facilities can ensure their generators provide continuous, reliable power, which is essential for patient care and facility operations during power outages.

  • A minimum of two independent power sources. Healthcare facilities must have at least two independent power sources for their EES to ensure power supply redundancy and reliability. One source is usually the public utility, and the other is an on-site power source such as a diesel generator.
  • On-site power source sizing and reliability. The on-site power source must be adequately sized to supply the entire EES and ensure it can handle the full load of the life safety, critical, and equipment branches. Regular assessment and testing ensure the on-site power meets the facility’s maximum demand requirements.
  • Location and protection of generators. Generators must be in areas that minimize the risk of damage from environmental factors such as flooding, fire, or extreme weather to ensure continuous operation and accessibility for maintenance under adverse conditions. Generators can be installed indoors in a dedicated room with a 2-hour fire resistance rating or outdoors in a suitable enclosure.
  • Coordination of overcurrent protective devices. These devices must be coordinated to ensure minimal disruption during faults, prevent extensive power interruptions, and protect against overloads and short circuits. Proper selection and coordination of OCPDs in the on-site power’s electrical path is necessary.
  • Ground-fault protection guidelines. Ground-fault protection must be included without automatic disconnection for on-site power sources to prevent unnecessary power interruptions due to ground faults while ensuring safety.
  • Maintenance and testing protocols. On-site power and associated equipment must be regularly maintained and tested to ensure reliability and compliance with NFPA 99 standards. Monthly and annual testing under load conditions is required to confirm the system’s ability to meet the 10-second transfer.
  • Transfer switch requirements. During a normal power system failure, automatic transfer switches (ATS) ensure a quick transition to the on-site power source. The ATS must be installed and maintained to facilitate immediate power transfer within the specified time limits.
  • Fuel supply and storage. Adequate fuel supply must be maintained to ensure uninterrupted generator operation and continuous power during prolonged utility outages. Regular inspection and replenishment of fuel supply are required, with consideration for emergency refueling plans.
  • Documentation and compliance records. Thorough documentation of maintenance, testing, and compliance activities is required to provide evidence of compliance with NFPA 99 and facilitate audits by the authority having jurisdiction (AHJ). Ensure detailed logs of all activities, including test results and maintenance actions.

Register for our next CHEPP online class!

Understanding and implementing NFPA 99 is crucial for ensuring the safety and reliability of the essential electrical system. Becoming a Certified Healthcare Emergency Power Professional (CHEPP®) will give you the knowledge and skills to ensure your facility meets all regulatory requirements, demonstrating your commitment to maintaining a safe healthcare environment.

Course Benefits:

  • In-Depth Knowledge: Learn about the latest updates and recommendations in the 2025 NFPA 110, NFPA 111, and the 2024 edition of NFPA 99.
  • Best Practices: Implement best practices for routine maintenance and operational testing to enhance the reliability of your EPSS.
  • Advanced Technologies: Explore new technologies and methods for monitoring and testing, including automated systems.
  • Comprehensive Record-Keeping: Maintain detailed records and prepare for inspections by the authority having jurisdiction.

Enroll in our course to improve your skills in maintaining, testing, and ensuring compliance. Secure your spot now!