Cov cuab yeej siv dej feem ntau yog nruab rau hauv cov chaw hauv qab no:
Hauv qab daus lossis chav tsev khoom siv nyob rau hauv thawj pem teb: Qhov no yog qhov chaw tshaj plaws installation. Cov cuab yeej siv dej tuaj yeem ntsia tau rau hauv cov khoom siv hauv chav ua haujlwm ntawm thawj lossis thib ob hauv pem teb hauv qab daus ntawm lub zej zog, lossis yog tias tsis muaj hauv qab daus, nws tuaj yeem ntsia tau rau hauv cov khoom siv hauv chav tsev ntawm thawj lub tsev hauv zej zog.
Pem teb sab saum toj lossis tshuab chav: rau cov khoom siv hluav taws xob nce, cov khoom siv dej kuj tseem tuaj yeem muab tso rau hauv av sab saum toj lossis tshuab chav. Qhov no kom ntseeg tau tias cov dej txhaws qhov kom txog qhov chaw tso dej txaus, txo cov dej ntws tsis pom, thiab txhim kho cov dej khov kho dej siab thiab dej ntws.
Hauv pem teb nruab nrab: Qee zaum, cov khoom siv dej tuaj yeem ntsia tau rau hauv pem teb nruab nrab, xws li nruab nrab ntawm 10th thiab 20th pem teb. Qhov no tuaj yeem txo qhov kev ncua deb thiab siab poob ntawm cov dej thiab txhim kho tag nrho cov dej kom zoo.