I'm back on the headrest trail. The big ones on the rear seat are just impractical as they cannot be removed without tilting the seat back forward because they hit the roof. They also reduce rear visibility which is a precious commodity.
From what I can see, the latest in-force version of ADR 22/00 2006 concerning head restraints still only mandates them for front seats, but I can see where I think Ineos Australia have opted to use the minimum height limit of 700mm from seat base to lowest adjusted height on the rear seats out of an abundance of caution.
22.2. PROVISION, LOCATION AND SIZE
22.2.1. A ‘Head Restraint’ must be provided for each front ‘Outboard Seating Position’. It may be provided with vertical and lateral adjustable mounting, and may be removable without the use of tools.
22.2.2. The ‘Head Restraint’ must be so designed that:
22.2.2.1. it presents an impact surface which extends between 2 planes not less than 115 mm apart and normal to the ‘Torso Line’; and
22.2.2.2. the upper boundary of the impact surface is not less than 700 mm above the ‘Seating Reference Point’ measured along the ‘Torso Line’, for any position of adjustment which may be provided.
For reference, the smaller centre headrest in the Grenadier is only 660mm above the seat base.
I checked in our 2018 VW Golf which has the same type of cut-over seat back headrests and they are indeed more than 700mm above the seat base. So I am still trying to find if there is some other piece of possibly state-based legislation that mandates this minimum dimension on rear head restraints, thereby setting an effective national design rule by default.
I still want to see if Ineos can swap them over as the big headrests just bug the crap out of me.