Hauv cov txheej txheem kev muag khoom, cov khob ntawv feem ntau muab tso ua ke thiab kaw hauv cov ntim yas. Txawm hais tias lawv tuaj yeem pom thiab kov tau, cov neeg feem coob tsis paub qhov zoo. Ntawm no yog yuav ua li cas xaiv cov khoom khob rau cov neeg siv khoom.
Saib ntawm kev ntim khoom thiab kev txheeb xyuas: feem ntau, cov khob ntawv yuav tsum muab ntim rau hauv lub hnab yas, thiab lub hnab ntim khoom yuav tsum tsis txhob raug puas tsuaj. Cov khob ntawv nrog cov ntim xoob yog qhov ua rau muaj kuab paug ib puag ncig, thiab kev nyiam huv tsis tuaj yeem lav. Lub npe thiab chaw nyob ntawm cov chaw tsim khoom, tus qauv tswj hwm ntawm cov khoom, hnub tsim khoom, lub sijhawm siv tau, thiab lwm yam yuav tsum tau qhia rau ntawm pob khoom. Kev ua tau zoo ntawm cov khoom khob ntawv yuav tsum ua raws li QB/T2294 1997 daim ntawv khob tus qauv, lossis cov qauv kev lag luam. Txawm li cas los xij, cov ntsuas kev tu cev yuav tsum ua raws li QB11680-1989 tus qauv tu cev rau cov ntawv hauv qab rau ntim khoom noj.