1.1 Kev ceev faj tus kheej, cov cuab yeej tiv thaiv thiab cov txheej txheem xwm txheej ceev
Siv cov cuab yeej tiv thaiv tus kheej.Tsis txhob tsim cov hmoov av.Tsis txhob ua pa vapors, pos huab lossis
gas.Xyuas kom muaj qhov cua txaus.Tsis txhob ua pa plua plav.
1.2 Kev ceev faj ib puag ncig
Tiv thaiv kom tsis txhob xau lossis nchuav ntxiv yog tias muaj kev nyab xeeb ua li ntawd.Tsis txhob cia cov khoom nkag mus rau hauv cov dej ntws.
Kev tso tawm mus rau ib puag ncig yuav tsum zam.
1.3 Cov txheej txheem thiab cov khoom siv rau kev ntim thiab tu
Khaws thiab npaj pov tseg yam tsis tsim plua plav.Sweep thiab shovel.Khaws rau hauv
haum, kaw ntim rau pov tseg.
