In inert gas clean agents that are not liquified, what condition indicates the container should be refilled?

• A. A drop in ambient temperature
• B. A loss in pressure greater than 5 percent (adjusted for temperature)
• C. Any decrease in article weight
• D. Visual color change

Answer: (B)

For inert gas clean agents stored as nonliquified gas, the amount of agent left in a cylinder is reflected directly by cylinder pressure. Temperature affects pressure, so the test uses a temperature-adjusted comparison. If the pressure drops more than about 5% after accounting for ambient temperature, it indicates a loss of gas (leak or depletion) and the cylinder should be refilled. Other signs like a temperature change, a weight decrease, or a visual color change aren’t reliable indicators for this type of agent—the gas is colorless and not in liquid form, and weight or visual cues aren’t practical ways to gauge remaining quantity.