Tsis ntev los no, kev lag luam PVC hauv tsev tau nce ntxiv ntau heev. Tom qab Hnub National, kev xa khoom thiab kev thauj mus los ntawm cov khoom siv tshuaj lom neeg raug thaiv, cov tuam txhab ua tiav cov khoom lag luam tsis txaus los txog, thiab kev txaus siab yuav khoom tau nce ntxiv. Tib lub sijhawm, cov khoom muag ua ntej ntawm cov tuam txhab PVC tau nce ntxiv ntau heev, qhov kev thov zoo, thiab kev muab khoom nruj, tsim kev txhawb nqa tseem ceeb rau kev ua lag luam kom nce sai.
