Kev daws rau qhov tawg ntawm qhov nruab nrab zaus hluav taws xob nqi hluav taws xob:

1. Txais qhov tsim nyog kom qhuav thiab cua sov kom tswj tau qhov siab tshaj plaws vapor siab hauv cov nqi nruab nrab zaus;

2. Ntxiv cov tshuaj tiv thaiv kev tawg xws li cov tshuaj tiv thaiv kev tawg mus rau qhov nruab nrab zaus them nyiaj kom ua rau huab cua permeability ntawm lub cev tawv thiab txo qis hauv vapor siab ntawm cov castable.