1. Tsis muaj residue nyob rau hauv tag nrho cheeb tsam, RFU< 5;
2. Kev ua haujlwm siab zoo: Raws li qhov sib txawv ntawm cov tshuab kho qhov muag thiab cov teeb tsa laser, kev sib tw tuaj yeem nyob hauv 0.5 vib nas this;
3. Tag nrho cov khoom siv kho qhov muag yog tsim los ntawm nws tus kheej, ua tiav thiab sib sau ua ke, thiab cov tub ntxhais laser tswj tau tsim nws tus kheej;
4. Laser optics thiab cov txheej txheem kev daws teeb meem tuaj yeem hloov kho tau yooj yim raws li cov neeg siv khoom sib txawv
