1 Since a main vertical zone (MVZ) may be up to 48 m long, any vessel above 96 m normally has 3 or
more MVZs, and the SRtP regulations apply. If, however , the extreme forward and/or aft zone(s) of the ship
contain only appendages/voids/tanks without equipment, systems or storage, these zones may be considered
to be of low risk and hence exempted from the MVZ criteria.