ash ▁Prote ction ▁System ▁( WH IP S ) ▁is ▁a ▁system ▁to ▁protect ▁against ▁autom ot ive ▁wh i pl ash ▁inj uries ▁introduced ▁by ▁Vol vo ▁in ▁ 1 9 9 8 . ▁It ▁was ▁launched ▁when ▁the ▁Vol vo ▁S 8 0 ▁was ▁released ▁for ▁the ▁ 1 9 9 9 ▁model ▁year ▁and ▁has ▁since ▁been ▁part ▁of ▁the ▁standard ▁equipment ▁of ▁all ▁new ▁Vol vo ▁cars . ▁ ▁Details ▁A ▁WH IP S ▁equ ipped ▁seat ▁is ▁designed ▁so ▁that ▁the ▁entire ▁back rest ▁helps ▁to ▁protect ▁the ▁front ▁occup ant ' s ▁neck ▁in ▁a ▁case ▁of ▁a ▁rear ▁impact . ▁When ▁the ▁system ▁is ▁deployed , ▁the ▁front ▁seat ▁back rest s ▁and ▁head rest s ▁are ▁lower ed ▁back ward ▁to ▁change ▁the ▁se ating ▁position ▁of ▁the ▁driver ▁and ▁front ▁seat ▁passenger . ▁The ▁main ▁energy ▁is ▁absor bed ▁via ▁a ▁pivot ▁at ▁the ▁base ▁of ▁the ▁seat – me chan ism ▁which ▁allows ▁the ▁seat ▁to ▁move ▁around ▁the ▁occup ants ▁actual ▁hip ▁joint ▁while ▁moving ▁rear ward ▁to ▁abs orb ▁additional ▁energy . ▁A ▁piece ▁of ▁metal ▁inside ▁the ▁back rest ▁h inge ▁de forms , ▁absor bing ▁more ▁energy . ▁The ▁h inge ▁piece ▁needs ▁to ▁be ▁replaced ▁after ▁having ▁been ▁deployed . ▁ ▁According ▁to ▁Vol vo ' s ▁traffic ▁accident ▁research ▁team , ▁the ▁WH IP S ▁equ ipped ▁seat ▁resulted ▁in ▁a ▁ 3 3 % ▁reduction ▁in ▁short ▁term ▁injury ▁and ▁a ▁ 5 4 % ▁reduction