Here’s a video of a VESDA system at work.
Some NFPA references about this installation.
188.8.131.52 Air Sampling~Type Smoke Detector.
17.7,3.6.1 Each sampling port of an air sampling-type smoke
detector shall be treated as a spot-type detector for the pur-
pose of location and spacing.
184.108.40.206.2 Maximum air sample transport time from the far-
thest sampling port to the detector shall not exceed 120 seconds.