▁major ▁economic ▁consequences . ▁ ▁Based ▁on ▁this ▁the ▁type ▁of ▁ship ▁is ▁specified ▁for ▁each ▁operation : ▁Class ▁ 1 ▁D P ▁units ▁with ▁equipment ▁class ▁ 1 ▁should ▁be ▁used ▁during ▁operations ▁where ▁loss ▁of ▁position ▁is ▁not ▁considered ▁to ▁end anger ▁human ▁lives , ▁cause ▁significant ▁damage ▁or ▁cause ▁more ▁than ▁minimal ▁poll ution . ▁Class ▁ 2 ▁D P ▁units ▁with ▁equipment ▁class ▁ 2 ▁should ▁be ▁used ▁during ▁operations ▁where ▁loss ▁of ▁position ▁could ▁cause ▁personnel ▁injury , ▁poll ution ▁or ▁damage ▁with ▁great ▁economic ▁consequences . ▁Class ▁ 3 ▁D P ▁units ▁with ▁equipment ▁class ▁ 3 ▁should ▁be ▁used ▁during ▁operations ▁where ▁loss ▁of ▁position ▁could ▁cause ▁fatal ▁acc idents , ▁severe ▁poll ution ▁or ▁damage ▁with ▁major ▁economic ▁consequences . ▁ ▁Fail ure ▁ ▁L oss ▁of ▁position , ▁also ▁known ▁as ▁run off , ▁can ▁be ▁a ▁threat ▁to ▁safe ▁operations ▁and ▁the ▁environment , ▁including ▁possible ▁loss ▁of ▁life , ▁injury , ▁damage ▁to ▁property ▁or ▁the ▁environment , ▁and ▁loss ▁of ▁reputation ▁and ▁time . ▁Inc ident ▁records ▁indicate ▁that ▁even ▁vessels ▁with ▁redundant ▁dynamic ▁position ing ▁systems ▁are ▁subject ▁to ▁occas ional ▁loss ▁of ▁position , ▁which ▁can ▁be ▁due ▁to ▁human ▁error , ▁proced ural ▁failure , ▁dynamic ▁position ing ▁system ▁fail ures , ▁or ▁bad ▁design . ▁▁ ▁Dynamic ▁position ing ▁failure ▁results ▁in ▁an ▁in ability ▁to ▁maintain ▁position ▁or ▁heading ▁control , ▁and ▁can ▁be ▁a ▁dr ift ▁off ▁caused ▁by ▁ins u fficient ▁thrust , ▁or