Daim Ntawv Thov

Los ntawm kev siv cov hloov pauv tsis siv neeg hauv cov neeg caij tsheb elevators, kev ntseeg tau thiab kev nyab xeeb ntawm cov elevators tuaj yeem txhim kho. Nws tuaj yeem ua kom lub elevator txuas ntxiv ua haujlwm li qub thaum muaj hluav taws xob tsis ua haujlwm lossis lwm yam xwm txheej ceev, ua kom muaj kev nyab xeeb thiab kev nplij siab rau cov neeg caij tsheb. Tib lub sijhawm, lub hloov pauv tsis siv neeg kuj tseem tuaj yeem ceeb toom raws sijhawm thiab muab kev sib txuas lus thaum muaj xwm txheej ceev, muab kev tiv thaiv kev nyab xeeb siab dua rau cov neeg caij tsheb.