1. Lub hau kev sib tsoo yog cov khoom tsis yooj yim, uas yuav tsum tau ua nrog kev saib xyuas kom tiv thaiv kev tawg thiab kev puas tsuaj.
2. Kev sib tsoo lub log yuav tsum muab cia rau ntawm lub txee lossis hauv lub thawv kom tiv thaiv kom tsis txhob ya raws.
3. Cov nplaum daim ntawv cog lus sib tsoo lub log yuav tsum tsis txhob sib chwv nrog cov tshuaj alkali. Tom qab lub sijhawm khaws cia dhau ib xyoos, nws yuav tsum dhau qhov kev paub ua lub zog ua ntej siv nws.
