UkuthethelelwaUkwakheka kosayizi wenqubo nokukhethwa kwenqubo kwenziwa ngasikhathi sinye, ngakho-ke, amaphuzu alandelayo kufanele anake lapho uhlela usayizi wenqubo:
(1) Landela umthetho wevolumu ehlala njalo, usayizi wenqubo yokwakheka kufanele uvumelane namaphoyinti asemqoka wenqubo ngayinye; Ngemuva kwenqubo, ivolumu ngaphambi kokuthi inqubo ilingane nevolumu eliphelele ngemuva kwenqubo. I-volume ephelele isho isamba senani levolumu yemikhiqizo eqediwe etholwe yinqubo kanye nevolumu yokulahleka kwezinto ezibonakalayo okwenzeka kule nqubo.
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(3) Usayizi wemikhiqizo eqediwe etholwe kwinqubo eyodwa kufanele ikwazi ukwenza inqubo elandelayo iqhubeke kahle. Isibonelo, lapho kuqala ukudonsa isikhathi eside bese udidanisa, awukwazi ukudonsa isikhathi eside, ngaphandle kwalokho ukukhathazeka kuzohlelwa futhi kugobe.
(4) Lapho wenza izingxenye, kuyadingeka ukuqinisekisa ukuthi ingxenye ngayinye inevolumu eyanele.

(5) laphoUmlilo omningi, amathuba okushisa okuphakathi komlilo ophakathi nendawo kufanele abhekwe, njengosayizi weInqubo yokwakha, Umlilo ophakathi nendawo, umkhiqizo oqediwe ungabekwa ekufuneni okulithayo nokunye.
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(7) Isikhathi esideUkukhokhiswa ShaftUbude obudingekayo obukhulu obudingayo bunembe kakhulu, kufanele kulinganiswe ukuthi usayizi wobude buzonwetshwa kancane lapho ugqoka.
Inani lekhanda lokusika leUkukhokhiswa Shaftkufanele ahlangabezane nezidingo.