Umphambili ufumana amandla empembelelo, athi asasazwe yibhampa yangaphambili kwiibhokisi zokufunxa amandla kumacala omabini aze adluliselwe kuloliwe osekhohlo nasekunene wangaphambili, emva koko uye kuwo wonke ulwakhiwo lomzimba.
Umva uyachatshazelwa yimpembelelo yamandla, kwaye amandla empembelelo agqithiselwa yi-bumper yangasemva kwibhokisi yokufunxa amandla kumacala omabini, ukuya ngasemva nasekunene kaloliwe ongasemva, kwaye emva koko kwezinye izakhiwo zomzimba.
Ii-bumpers zempembelelo ezisezantsi ziyakwazi ukujamelana nempembelelo, ngelixa ii-bumpers zempembelelo eziphezulu zidlala indima yokuhanjiswa kwamandla, ukusabalalisa kunye nokunciphisa, kwaye ekugqibeleni ukudluliselwa kwezinye izakhiwo zomzimba, kwaye emva koko zithembele kumandla okwakheka komzimba ukuchasa.
I-Amerika ayithathi i-bumper njengendlela yokukhusela: i-IIHS eMelika ayithathi i-bumper njengendlela yokukhusela ukhuseleko, kodwa njenge-accessory yokunciphisa ilahleko ye-low-speed collision. Ke ngoko, uvavanyo lwe-bumper lukwasekwe kumbono wendlela yokunciphisa ilahleko kunye neendleko zokugcina. Kukho iintlobo ezine zeemvavanyo ze-IIHS ze-bumper crash, ezizimvavanyo zengozi ngaphambili nangasemva (i-speed 10km/h) kunye novavanyo lwengozi yangaphambili nangasemva (isantya se-5km/h).
