Pipelines casings regulated by PHMSA require the mitigation of shorted casings. One method that aligns with the PHMSA guidelines is the utilization of NACE SP0200. This standard recommends using a corrosion-inhibiting gel filler that transforms from the viscosity of water to a high-viscosity gel, providing effective sealing and corrosion protection. However, concerns exist regarding the potential loss of the inhibitor filler during its application. While some operators opt for pneumatic pressure tests instead of hydrotests to minimize contamination and reduce costs, the rapid loss of pressure in a pneumatic test does not equate to a rapid loss of corrosion inhibitor gel. To address this concern, a custom-designed pressure chamber was employed to simulate casing defects ranging from 5 to 13 mm in the worst-case scenario (6 o'clock position). Corrosion inhibitor gel filler was injected into the chamber and then pressurized to a maximum of 20 psia (~1.4 bar). The pressure was released through the different simulated defects and the corrosion inhibitor filler loss was recorded. The study revealed that inhibitor retention remained satisfactory. In the worst-case scenario, the maximum loss of corrosion inhibitor gel filler recorded was approximately 1 to 5% of the injected solution.