Ukuze uthuthukise izindleko zenqubo yokukhiqiza amakhemikhali futhi ugcine umkhiqizo osezingeni eliphezulu, udinga ukubamba uketshezi lwenqubo olumele ukuze luhlaziywe elabhorethri njalo. Ukusampula (okwaziwa nangokuthi i-spot sampling, i-field sampling, noma i-rational sampling) kusiza ukuqinisekisa izimo zenqubo nokuqinisekisa ukuthi umkhiqizo okhiqizwayo uhlangabezana nezimfuneko zangaphakathi noma ezisekelwe kumakhasimende.
Imithetho eyisisekelo yokukhetha amasampula
1: Isampula kumele imele isimo senqubo, futhi i-probe kufanele isetshenziswe ukukhipha isampula phakathi kwepayipi yenqubo ukuze kugwenywe ukuguquka kwesigaba ngesikhathi sokuthuthwa kwesampula.
2: Isampula kumele ibe sesikhathini. Ukunciphisa isikhathi sokuthuthwa kusuka endaweni yokukhipha kuya elabhorethri kuyasiza ukuqinisekisa ukuthi izimo zenqubo zibonakaliswa ngokunembile.
3: Isampula kumele ibe msulwa. Gwema indawo efile yepayipi phezulu kwesitsha sesampula futhi uvumele ukuhlanza nokuhlanza okwanele uhlelo lokuhlola ukuze unciphise amathuba okungcola.
Cabanga ngoketshezi lwenqubo lapho igesi incibilikiswa khona. Uma izinga lokushisa likhuphuka futhi ingcindezi yehla, igesi encibilikisiwe ingabila iphume kusampula. Noma cabanga ngesampula yegesi enokushisa okuphansi kanye nengcindezi ephezulu, okungabangela ukuthi uketshezi luhlangane futhi luhlukane nesampula. Esimweni ngasinye, ukwakheka kwesampula kuyashintsha ngokuyisisekelo, ngakho-ke akusakwazi ukumelela izimo zenqubo.
Ngenxa yezizathu ezingenhla, kubalulekile ukusebenzisaamabhodlela esampulaukuqoqa igesi noma igesi encibilikisiwe ukuze kulondolozwe isigaba esifanele futhi kulondolozwe ukumelela kwesampula. Uma igesi inobuthi, isilinda nayo iyasebenza ekuvikeleni uchwepheshe wesampula kanye nendawo ezungezile ekukhishweni kwentuthu noma kokukhishwa komoya.
Isikhathi sokuthunyelwe: Feb-17-2022