What does the term "listed" imply about equipment or materials?

The term "listed" in relation to equipment or materials signifies that those items are included in a list published by an approved organization, such as Underwriters Laboratories (UL), Factory Mutual (FM), or similar entities. This indicates that the product has been tested and meets specific safety and performance standards set forth by those organizations. Being "listed" ensures that the equipment or materials are deemed reliable and safe for use in various applications, particularly in compliance with codes and regulations governing sprinkler systems and fire protection.

This certification process is crucial for ensuring that the products perform as expected under specific conditions and are suitable for installation in fire protection systems. Items that are not "listed" may not have had the same level of scrutiny and therefore could present a risk in terms of safety and effectiveness.