It will need to be secure if you fit one; this is one of the major checks the scrutineers undertake. Heavy metal objects moving around in the cabin is not good for obvious reasons.
There is space in front of the seats on the floor to fit one using this kind of bracket x2. Just need to think about the best place to mount should the worse happen and you need to act fast
https://www.ebay.ie/itm/Lifeline-Hand-H ... Sw-29ZWzUb