Nws tau dav siv hauv roj av drilling kev kawm.
siv
Nws yog qhov yuav tsum tau tawm ntawm lub tshuab tso tawm kom sib txuas thiab cov nkev phom sij kom tshem tawm nws cov phom sij rau ib puag ncig thiab kev nyab xeeb.
Cov kev ceev faj rau kev siv
1. Lub chaw muaj kev nyab xeeb ntawm lub tshuab hluav taws xob thiab cov neeg ua hauj lwm (qhov chaw nyob nyab xeeb yog 60 metres).
2. Mob siab rau kev tiv thaiv ntawm cov khoom siv hluav taws xob tiv thaiv kom tsis txhob muaj xwm txheej tsis raug puas tsuaj los ntawm kev puas tsuaj rau cov khoom siv hluav taws xob.