Isikrini sewindi lensimbi esingenalutho sibizwa nangokuthi iwindi lesinambuzane esingenasici, isikrini sefasitela lokuphepha. Yenziwe ngekhwalithi ephezulu yensimbi engagqwali ngokuqina nokusebenza okungapheli. Insimbi yensimbi engenacici ingamelana nokugqwala, ukugqwala, ukushisa, i-alkaline, ngakho-ke ingasetshenziswa ezindaweni ezinzima zamafasitela, iminyango kanye nezikrini zemipheme ukuvimbela izinambuzane.