Which of the following require re-acceptance testing to be performed?

• A. Smoke detectors that have been added or removed
• B. Changes to control relay
• C. Changes to system hardware
• D. Changes to the battery type

Answer: (A)

Re-acceptance testing is done after changes to a fire alarm system to confirm the whole system still meets the design and code requirements. Adding or removing smoke detectors directly changes the initiating devices in the system, which affects coverage, zone configuration, addresses, and how the panel interprets alarms. Because these changes can alter detection timing, supervision, and interconnections, re-acceptance ensures that all devices are correctly integrated and that the system will respond as intended across all parts of the installation.

Changing a control relay or other system hardware, while still requiring proper testing to verify operation, does not by itself alter the detection coverage or the overall configuration in the same way, so it typically doesn’t invoke re-acceptance testing. Changing the battery type impacts power considerations and reliability, which are tested through power and battery checks rather than re-acceptance.