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NASA designed an inflatable habitat intended for space whose exterior incorporates an expandable layer known as the bladder – the main pressure shell of a module to which astronauts may reside while off-world. The bladder is made from a polymer material and is surrounded by protective layers to ensure it is not damaged and does not leak. On every module, there are two areas where the bladder and other flexible layers interface with the ends of a cylindrical core, at the bulkheads. Seals between the non-metallic bladder and the metallic bulkhead are critical in maintaining a safe pressurized environment for astronauts to live and work. With both bulkhead plates assembled, RTV silicone is deposited in specially designed channels which are sandwiched between the plates. After the channels are filled, a cure-in-place seal is formed between the bladder and the bulkhead. The RTV sealing method worked successfully during prototype testing as confirmed by a helium leak test and post-test visual inspection of the seals. In prototype testing, this method created a consistent and reliable seal between the bladder and bulkhead assembly replicated from the inflatable module design. The RTV sealing method may benefit terrestrial applications that may demand cure-in-place internal seals. The method could also innovate manufacturing processes for components by enhancing the speed of assembly while increasing seal integrity.