After the 6 meter emergency gate road authorities came with the question to increase this length in order  to provide access for larger emergency vehicles such as fire fighter trucks; after all the wider the median gate the faster they can pass through.
So SPIE came up with a 9 meter boom length including a pivoting post to ensure the crash resistance according the EN1317-2.

Also for this CADO emergency gate there could be a cost saving advantage in operating a number of them on one and the same hydraulic unit.