[T.B. Yoits]

You do know that lasers can be used to pick up sound vibrations from window glass from a distance right? If the SCIF had a window it was not secure.

USAF1985 mentioned in his comment that they had white noise generators.

https://digiscan-labs.com/products/dng-2300/

"Suppresses wall contact microphones, window laser systems and wired microphones inside walls, voids and air ducts."

[USAF1985]

Thank. All of our windows have the generators.