What does the term 'listed' refer to in fire alarm systems?

The term 'listed' in fire alarm systems refers to equipment that has been evaluated by an authoritative testing organization and found to meet specific standards for safety and performance. This certification ensures that the components are suitable for their intended use, particularly in protecting lives and property from fire hazards. When a fire alarm system component is ‘listed’, it indicates that it has undergone rigorous testing and meets the safety criteria set forth by relevant codes and standards such as those established by Underwriters Laboratories (UL) or other similar entities. This designation is crucial for ensuring that the systems installed in buildings are dependable and compliant with fire safety regulations.

In contrast, devices without certification or those that do not meet established standards lack the necessary evaluation to assure their reliability in a fire emergency. Temporary installations may not necessarily be listed, as the term is specific to equipment that has been officially designated as safe and effective for permanent use.