Usiba lwerhanisi ayinalo ivumba elikhethekileyo kwaye iyimathiriyeli yobushushu elunge kakhulu. Isetyenziswa ngokubanzi njengento yokuzalisa iimpahla kunye neebhedi. Iintsiba zerhanisi kunye nerhanisi zineengenelo ezininzi ezinje ngokusezantsi okukhulu, ukuthamba okuhle, umngxuma ophezulu, njalo njalo. Iintsiba ezilungileyo ngaphandle kwevumba. Ukongeza, iintsiba zerhanisi zinokusetyenziswa njengokuhombisa okanye ukwenza imisebenzi yezandla.