scope:

This standard covers performance requirements for emergency and standby power systems providing an alternate source of electrical power to loads in buildings and facilities in the event that the primary power source fails.

Power systems covered in this standard include power sources, transfer equipment, controls, supervisory equipment, and all related electrical and mechanical auxiliary and accessory equipment needed to supply electrical power to the load terminals of the transfer equipment.

This standard covers installation, maintenance, operation, and testing requirements as they pertain to the performance of the emergency power supply system (EPSS).

This standard does not cover the following:

Application of the EPSS 

Emergency lighting unit equipment 

Distribution wiring 

Utility service when such service is permitted as the EPSS 

Parameters for stored energy devices 

The equipment of systems that are not classed as Level 1 or Level 2 systems in accordance with Chapter 4 of this standard.

*This standard does not establish criteria for stored energy systems.

The selection of any of the following is not within the scope of this standard:

Specific buildings or facilities, or both, requiring an EPSS

Specific loads to be served by the EPSS

*Assignment of type, class, or level to any specific load

Purpose. This standard contains performance requirements for an EPSS.

It is the role of other NFPA standards to specify which occupancies require an EPSS and the applicable level, type, and class. This standard does not specify where an EPSS is required.

This standard also is intended to provide guidance for inspectors, designers, installers, manufacturers, and users of EPSSs and to serve as a vehicle for communication between the parties involved. It is not intended as a design manual.

Compliance with this standard is not intended to exempt the parties involved from their respective responsibilities for the design, installation, maintenance, performance, or compliance with other applicable standards and codes.

Application. This document applies to new installations of EPSSs, except that the requirements of Chapter 8 shall apply to new and existing systems. Existing systems shall not be required to be modified to conform, except where the authority having jurisdiction determines that nonconformity presents a distinct hazard to life.