Retrofitting a clean agent into an existing fire extinguishing system shall result in what type of system?

• A. A listed system
• B. An approved system
• C. A system that is listed
• D. A system that is listed or approved

Answer: (D)

When you retrofit a clean agent into an existing fire extinguishing system, the resulting setup must have formal recognition that confirms it’s been evaluated for use with that agent. This recognition comes in two forms: listing and approval. Listing means a recognized testing laboratory has evaluated the system design and components and found them to meet the applicable standards for clean agent use. Approval means the authority having jurisdiction (or the recognizing body) has accepted the modified system for the intended installation.

Because a retrofit changes how the system will perform—potentially affecting agent compatibility, discharge characteristics, detection, and reliability—the modified system should be either listed or approved. This ensures it has been reviewed and accepted for safety and performance. That’s why the best choice is a system that is listed or approved.