1. Txog kev tsim kho thiab kev ua vaj tsev.
Lub pob zeb xuab zeb ua ke xuab zeb tom qab kev tsim kho pov tseg tuaj yeem siv los ua cov pob zeb ua pob zeb, thiab lub npov pob zeb sib xyaw ua ke tseem tuaj yeem siv rau txoj hauv kev txheej txheem. Cov pob zeb Slag tuaj yeem siv rau kev tsim kho, pob zeb sau cov ntawv, lub hauv paus pob zeb, thiab lwm yam Asphalt pov tseg rau ntawm txoj kev tsheb tuaj yeem ua kom tawg thiab ua tiav.
2. Ua cov khoom lag luam tsev.
Cib thiab lwm cov kev tsim kho cov khib nyiab rov ua dua tshiab tuaj yeem siv thiab kev tsim cov vuas pua tsev hauv av, rov ua dua tshiab cib thiab lwm yam khoom siv hauv tsev.
3. Cov txheej txheem rov qab ua dua cov Board thiab cov ntawv.
Cov ntoo khib nyiab siv ntoo tuaj yeem siv los ua cov ntaub ntawv raw khoom lossis ntawv sau rau cov ntawv ntim ntoo, thiab lwm yam.
4. Rau qhov xau.
Tom qab sib tsoo cov khib nyiab pov tseg rau cov khoom siv av nplaum, nws tuaj yeem siv cov khoom siv sib xyaw ua ke tsis yog ya cov hmoov tshauv, slag hmoov, hmoov zeb, thiab lwm yam.
