Isetshenziselwa ukugcwalisa ama-pores amahle ebusweni bamathayela aphucuziwe, okunikeza amathayili aphucuziwe umphumela wesibuko ohlala isikhathi eside. Inesikhunta esihlala isikhathi eside, ukumelana namabala, ukumelana nokugqokwa, ukumelana ne-asidi ne-alkali, njll. Kubaluleke kakhulu kubuchwepheshe besimanje bokupholisha bokulwa nokungcolisa. Izinto zokulungiselela.