A container in a clean-agent extinguishing system must be refilled or replaced if it experiences a loss of more than 5% of its original weight or a loss in original pressure of more than 3%. This requirement ensures the system maintains sufficient agent concentration for fire suppression.

Reference to Fire Inspector Documentation:

1. NFPA 2001 – Standard on Clean Agent Fire Extinguishing Systems (2022 Edition)

NFPA 2001, Section 7.3.2.1 states that a container must be refilled or replaced if the weight loss exceeds 5% or the pressure loss exceeds 3% from the original fill pressure.

These limits are set to maintain system effectiveness and ensure that a clean-agent system can properly discharge in case of a fire.

2. 2021 International Fire Code (IFC) – Chapter 9 (Fire Protection Systems)

IFC 904.10 requires that clean-agent systems be maintained per NFPA 2001 to ensure reliability.

Detailed Explanation of Answer Choices:

Option A (Correct): 3% pressure loss is the correct threshold beyond which a container must be replaced or refilled.

Option B (Incorrect): While 5% is correct for weight loss, it is not the correct value for pressure loss.

Option C (Incorrect): A 10% pressure loss is too high and would compromise system performance before reaching the replacement threshold.

Option D (Incorrect): 12% is well beyond the acceptable loss limit and would pose a significant safety risk.

Thus, the correct and verified answer is: A. 3