What action should follow changes to the design or installation when modifications occur?

• A. Re-verify design concentrations and control logic.
• B. Update vendor contact list only.
• C. Update emergency exit signage only.
• D. Update drawings, calculations, and operating manuals to reflect changes; re-verify design concentrations and control logic.

Answer: (C)

When changes are made to the design or installation, you must update all related documentation and re-check the system to ensure it still provides the intended level of protection. This means revising drawings, calculations, and operating manuals to reflect the new configuration, including any changes to agent quantities, distribution, piping, detection and release hardware, and control sequences. At the same time, re-verify design concentrations and control logic to confirm that the target agent concentration is still achieved in the protected spaces within the required time, and that actuation, interlocks, alarms, and sequencing operate as designed. This comprehensive update prevents hidden mismatches between the fieldwork and the documented design, which could otherwise compromise safety and performance. Updating only vendor contact information or only signage addresses non-critical aspects and does not ensure the system will perform correctly after modifications.