Ko tētahi painga nui o ngā papa rapa keri ko tōna kaha ki te whakaiti i te haruru me te wiri ki te whakataurite ki ngā momo maitai kē atu. He mārire ake te mahi a ngā mīhini taumaha kua whakauruhia ki ngā pūnaha keri papa rapa, he mea nui tēnei mō ngā papa hangahanga o te tāone nui me ngā ture haruru tino pakari. Ka mimitihia e ngā āhuatanga maori o te rapa ngā wiri, ka whakarei ake i te whakamarie o te kaiwhakahaere me te whakaiti i te ngenge i ngā wā roa o te mahi. Nā tēnei ka puta hengā papa ara kerihe kōwhiringa pai rawa atu mō ngā kaupapa e tata ana ki ngā hōhipera, ngā kura, ngā wāhi noho rānei. Hei tāpiri, ka whakaitihia e te wiri iti te taumahatanga ki raro i te mīhini, ka roa ake te roa o te ora o ētahi atu wāhanga pēnei i ngā roera me ngā sprocket. Mō ngā kaimahi kirimana e hiahia ana ki te whakapai ake i ngā āhuatanga o te wāhi mahi me te whakatutuki i ngā paerewa taiao, ko ngā papa keri i hangaia mai i te rapa kounga teitei te otinga tino pai.

I te wā e mahi ana i runga i ngā mata ngawari pēnei i te papa tā, ngā ara hikoi, ngā papa rānei o roto, ka ārai ngā papa rapa o te keri i ngā kino ka pā mai ki ngā ara maitai. Ko te āhua kore-whakakoi okeri papa rapaKa whakarite kia noho pūmau ngā mata kua oti, kia kore ai e hiahiatia he whakatikatika utu nui, he whakahou rānei i te mata. Nā tēnei ka pai ngā papa ara keri mō ngā kaupapa ā-rohe, ngā whakaritenga huihuinga, me ngā whare ahumahi e hiahiatia ana te tiaki i te papa. Kāore i rite ki ngā papa ara keri whakarewa, ka tohatohahia te taumaha e ngā momo rapa, ka whakaitihia te pēhanga whenua, ka ārai hoki i ngā kōhao. He maha ngā kamupene whakapaipai whenua me ngā kamupene ratonga e pai ake ana ki ngā papa keri nā te mea ka taea te mahi i runga i ngā whenua tairongo me te kore e waiho he tohu, e kino rānei te hanganga.