Radio-frequency (RF) leakage from shielded enclosures is minimized while ensuring applicable RF attenuation standards and access requirements of the Americans with Disabilities Act (ADA) by attaching an inflatable bladder to a door of an enclosure. Substantially surrounding the bladder is an electrically conductive material. When the bladder is inflated it makes contact with conductive material which in turn makes conductive contact with the door frame to create an RF seal. The use of the bladder and conductive material provides an improved RF seal and allows for the use of a low-profile threshold that permits ADA access to, and from, the enclosure.