A cikin aikin injin, sau da yawa ana cin karo da cewa girman mashin ɗin ba a yiwa alama ba.Gabaɗaya, abokan ciniki za su bayyana ma'aunin tunani tare da rubutu akan zane.Tabbas kowace kasa da yanki tana da nata ma'auni, amma ka'idojin gama gari sune kamar haka;

Na farko shine bisa ga ma'auni na duniya.Mai zuwa shine madaidaicin teburin haƙuri na 0-500mm ainihin girman tare da daidaito matakin 4 zuwa 18:

Bisa ka'idojin kasa da kasa, na biyu ya dace da yankan karfe da sarrafa tambarin gaba daya

Girman layi: girman waje, girman ciki, girman mataki, diamita, radius, nisa, da dai sauransu

Girman kusurwa: girman da yawanci ba ya nuna ƙimar kwana, misali, kusurwar dama na digiri 90.

Haƙuri na siffa yana nufin jimlar bambancin da aka ba da izini ta hanyar siffa guda ɗaya na ainihi, wanda aka bayyana ta hanyar yanki na juriya, wanda ya haɗa da abubuwa hudu na siffar haƙuri, shugabanci, matsayi da girma;Abubuwan da ke jure siffar siffar sun haɗa da madaidaiciya, laushi, zagaye, cylindricity, bayanin martaba na layi, bayanin martaba na saitin dabaran lebur, da dai sauransu.

Haƙurin matsayi ya haɗa da juriya na fuskantarwa, juriya na matsayi da juriyar runout.Duba teburin da ke ƙasa don cikakkun bayanai: