Sethula i-I-Crane Scale - Isixazululo esiphezulu sesisindo esinembile nesisebenzayo kuzilungiselelo zezimboni nezohwebo. Le divayisi emisha iklanyelwe ukwenza lula inqubo yokukala yemithwalo esindayo nenkulu, inikeze izilinganiso ezinembile nokusebenza okuthembekile. Ngezici zayo ezithuthukile nokwakhiwa okuhlala isikhathi eside, i-Crane Scale iyinketho ekahle yamabhizinisi afuna ukuthuthukisa imisebenzi yawo yokukala.
I-Crane Scale ifakwe iseli lomthwalo wekhwalithi ephezulu eliqinisekisa izilinganiso ezinembile nezingashintshi, ngisho nalapho usebenza ngezinto ezinkulu nezinzima. Ukwakhiwa kwayo okuqinile kanye nezinto ezisindayo kuyenza ifanelekele ukusetshenziswa ezindaweni ezinzima njengezindawo zokugcina izimpahla, izindawo zokukhiqiza, nezindawo zokwakha. Umklamo omangelengele wesikali usivumela ukuthi simelane nobunzima bokusetshenziswa kwansuku zonke, sinikeze ukwethembeka okuhlala isikhathi eside nokuqina.