Which of the following can provide the emergency power system for exit sign illumination?

The emergency power system for exit sign illumination can be provided by a variety of sources, each with its own advantages and suitability depending on the situation.

Storage batteries are commonly used in emergency lighting systems because they can be automatically charged during normal operations and provide immediate power when a loss of electricity occurs. This ensures that exit signs remain illuminated during an emergency situation.

Unit equipment is another effective source, which typically consists of battery-powered fixtures that are integrated into the normal lighting system. These units can switch to battery power automatically in an outage, making sure that exit signage is clearly visible to occupants evacuating the building.

On-site generators can also serve as a source of emergency power for exit signs. In larger buildings or facilities where a prolonged outage is a concern, these generators can keep the entire lighting system powered, including exit illumination, providing a reliable backup during emergencies.

Since all these systems are viable options for providing emergency power to illuminate exit signs, the correct response is that any of these solutions can be utilized. Thus, the most comprehensive answer includes all of them as potential sources, affirming that options A, B, and C are all acceptable means of ensuring that exit signs remain lit in case of an emergency.