. ▁ ▁If ▁a ▁ca ution ▁occurs ▁during ▁the ▁last ▁five ▁la ps , ▁the ▁counter ▁may ▁be ▁reset , ▁depending ▁on ▁the ▁track , ▁and ▁the ▁five ▁la ps ▁begins ▁on ▁the ▁en su ing ▁restart . ▁ ▁Many ▁prom ot ers ▁established ▁these ▁rules ▁far ▁before ▁NAS C AR ▁implemented ▁the ▁rule ▁nation ally ▁in ▁ 1 9 9 5 . ▁ ▁British ▁Super bi ke ▁Championship ▁motor cycle ▁racing ▁uses ▁a ▁similar ▁rule ▁after ▁two - third s ▁of ▁the ▁race ▁has ▁been ▁completed . ▁ ▁After ▁two - third s ▁of ▁the ▁race ▁la ps ▁( r ounded ▁down ) ▁have ▁been ▁completed , ▁if ▁a ▁ca ution ▁is ▁called , ▁the ▁race ▁will ▁be ▁extended ▁by ▁three ▁la ps . ▁ ▁For ▁example , ▁in ▁an ▁ 1 8 - lap ▁race , ▁the ▁ca ution ▁is ▁w aved ▁on ▁the ▁ 1 4 th ▁lap ▁( two - third s ▁is ▁ 1 2 ▁la ps ). ▁ ▁The ▁ca ution ▁period ▁last s ▁three ▁la ps , ▁with ▁the ▁safety ▁car ▁coming ▁in ▁at ▁the ▁end ▁of ▁the ▁ 1 6 th ▁lap , ▁effectively ▁calling ▁the ▁restart ▁on ▁Lap ▁ 1 7 . ▁which ▁would ▁be ▁two ▁la ps ▁remaining . ▁ ▁However , ▁British ▁Super bi ke ▁rules ▁state ▁that ▁once ▁two - third s ▁of ▁the ▁race ▁distance ▁is ▁passed , ▁the ▁first ▁three ▁la ps ▁of ▁a ▁ca ution ▁" do ▁not ▁count ▁as ▁race ▁la ps ," ▁similar ▁to ▁short -