1. Saib: Thaum xaiv lub khob ntawv pov tseg, tsis txhob' tsis txhob saib cov xim ntawm lub khob ntawv xwb. Don' tsis xav tias qhov xim dawb, qhov zoo nkauj dua. Txhawm rau ua kom lub khob zoo nkauj dua, qee lub khob khob cov tuam txhab ntxiv ntau cov tshuaj fluorescent whitening.
Thaum cov tshuaj phem no nkag mus rau tib neeg lub cev, lawv yuav dhau los ua cov carcinogens. Cov kws tshaj lij hais tias thaum xaiv lub khob ntawv, cov pej xeem yuav tsum tau thaij duab hauv qab lub teeb. Yog tias lub khob ntawv yog xiav nyob rau hauv lub teeb fluorescent, nws ua pov thawj tias tus neeg sawv cev fluorescent tshaj tus qauv, thiab cov neeg siv khoom yuav tsum siv ceev faj.
2. Pinch: Lub khob lub cev yog mos thiab tsis ruaj khov, ceev faj txog cov dej to. Tsis tas li ntawd, siv cov khob ntawv nrog cov phab ntsa tuab thiab tawv. Cov khob ntawv uas tsis tshua muaj lub cev hardness yog mos heev thaum pinched. Tom qab nchuav dej los yog dej haus, lawv yuav raug deformed heev thaum tuav, lossis txawm tias tsis tuaj yeem tuav tau, uas cuam tshuam rau kev siv.
Cov kws tshaj lij tau taw qhia tias feem ntau cov khob ntawv zoo tuaj yeem ntim dej rau 72 teev yam tsis muaj qhov xau, thaum qhov tsis zoo yuav pom dej hauv ib nrab teev.
3. Tsis hnov tsw: xim ntawm lub khob phab ntsa yog zoo nkauj, ceev faj kom txhob muaj kuab lom. Cov kws tshaj lij saib xyuas kev ua tau zoo tau taw qhia tias cov khob ntawv feem ntau muab tso ua ke. Yog hais tias lawv damp los yog paug, pwm yuav inevitably tsim. Yog li ntawd, cov ntawv khob uas ntub dej yuav tsum tsis txhob siv.
Tsis tas li ntawd, qee lub khob ntawv yuav raug luam tawm nrog cov xim zoo nkauj thiab cov lus. Thaum cov ntawv khob tau muab tso ua ke, tus number case nyob sab nraud ntawm lub khob ntawv yuav ua rau muaj kev cuam tshuam rau sab hauv ntawm lub khob ntawv qhwv ib ncig ntawm nws. Tus cwj mem muaj benzene thiab toluene, uas ua rau muaj kev phom sij rau kev noj qab haus huv. Yuav cov khob ntawv uas tsis muaj tus cwj mem lossis luam ntawv tsawg dua ntawm txheej txheej.
4. Siv: cais lub khob txias thiab khob kub, txhua tus muaj nws lub luag haujlwm. Cov kws tshaj lij thaum kawg tau taw qhia tias cov khob ntawv pov tseg peb feem ntau siv tau feem ntau muab faib ua khob dej txias thiab khob dej kub, txhua yam muaj nws lub luag haujlwm. Ib zaug" hloov chaw", nws yuav muaj kev cuam tshuam rau kev noj qab haus huv ntawm cov neeg siv khoom.