Ko ngā rawhi ngongo he mea here ki ngā pēhanga ngawari, pērā i ngā mea e kitea ana i roto i ngā mahi motuka me te kāinga. I ngā pēhanga teitei, inā koa me ngā rahi ngongo nui, me uaua te rawhi kia taea ai te tu atu i ngā kaha e whakawhanui ana i a ia me te kore e tukua te ngongo kia paheke atu i te taratara, kia puta rānei he turuturu. Mō ēnei mahi pēhanga teitei, ko ngā hononga kōpeketanga, ngā hononga matotoru, me ētahi atu hoahoa rānei te mea e whakamahia ana.

He maha ngā whakamahinga o ngā rawhi ngongo mō ngā mea ehara i te mea e tika ana kia whakamahia, ā, he maha ngā whakamahinga hei rīpene pumau ake i ngā wāhi katoa e whai hua ai te here whakakī i tētahi mea. He tino kaha te momo here tīwiri, ā, he maha atu ngā whakamahinga mō ngā mahi ehara i te paipa i ērā atu momo. Ka kitea ēnei rawhi hei mahi i ngā mea katoa mai i te whakairi i ngā tohu ki te pupuri i ngā whakatikatika whare ohorere (me ētahi atu mea rānei).

Ko tētahi atu āhuatanga whai hua: ka taea te whakapiko i ngā rawhi ngongo taraiwa-noke ki te mekameka-tā, ki te "hiame" rānei hei hanga i tētahi rawhi roa, ki te mea he maha āu, kia poto ake i te mea e hiahiatia ana e te mahi.

He mea whakamahi noa ngā rawhi ngongo i roto i te umanga ahuwhenua. Ka whakamahia ēnei ki ngā ngongo haukini waikore, ā, he mea hanga mai i te huinga o te maitai me te rino. He maha ngā wā ka whakakikoruatia ngā rawhi ngongo haukini waikore ki te cadmium hei ārai i te waikura me te pirau.