Kev ntsuas dej noo permeability yog siv los ntsuas lub peev xwm ntawm cov ntaub kom xa dej vapor nyob rau hauv qee yam mob. Lub khob dej noo permeability uas muaj cov desiccant lossis dej thiab kaw nrog cov qauv ntaub yog muab tso rau hauv qhov chaw kaw nrog qhov ntsuas kub thiab av noo. Tus nqi ntawm noo noo permeability thiab noo noo permeability yog xam raws li qhov loj ntawm qhov hloov pauv ntawm lub khob dej noo permeability (xws li cov qauv thiab cov desiccant lossis dej) dhau lub sijhawm. Moisture permeability tus nqi sawv cev rau qhov loj ntawm cov dej vapor dhau vertically los ntawm ib cheeb tsam ntawm cov qauv nyob rau hauv ib lub sij hawm raws li qhov ntsuas kub thiab av noo ntawm ob sab, qhia nyob rau hauv grams ib square meter ib teev [g/(m²·h)] los yog grams ib square meter ib 24 teev [g/(m²·24h)]. Moisture permeability tus nqi sawv cev rau qhov loj ntawm cov dej vapor dhau vertically los ntawm ib cheeb tsam ntawm cov qauv nyob rau hauv ib lub sij hawm raws li qhov ntsuas kub thiab av noo nyob rau ob sab, nrog ib chav tsev dej vapor siab sib txawv, qhia nyob rau hauv grams ib square meter ib pascal ib teev [g / (m²·pa·h)].
Cov nqi siab dua rau ob qhov ntsuas qhia tau zoo dua noo noo permeability ntawm cov ntaub. Qhov sib txawv tseem ceeb ntawm GB/T12704.1–2009 "Textiles - Test Methods for Moisture Permeability - Part 1: Hygroscopic Method" and GB/T12704.2–2009 "Textiles - Test Methods for Moisture Permeability - Part 1: Hygroscopic Method" and GB/T12704.2–2009 "Textiles - Test Methods for Moisture Permeability" nram qab no: nyob rau hauv txoj kev hygroscopic, ib tug desiccant muab tso rau hauv lub khob permeation, thaum nyob rau hauv txoj kev evaporation, distilled dej yog muab tso rau hauv lub khob permeation. Txoj kev evaporation yog ntxiv muab faib rau hauv txoj kev khob upright thiab lub khob inverted; lub khob inverted txoj kev tsuas yog siv tau rau cov ntaub ntawv tsis muaj dej thiab breathable. Hauv cov qauv uas tau hais los saum toj no, muaj ntau yam kev xaiv rau qhov kub thiab av noo ntawm qhov chaw kaw. Yog li ntawd, siv tib txoj kev sim ntawm tib tus qauv, qhov sib txawv ntawm qhov kub thiab txias yuav ua rau cov txiaj ntsig sib txawv.
Kev tawm dag zog ua kom hws ntau, thaum kev ua si sab nraum zoov inevitably cuam tshuam nrog cua thiab nag. Qhov no nthuav tawm qhov tsis sib xws: lub cev yuav tsum muaj peev xwm tiv thaiv los nag thiab daus los ntawm kev ntub dej thaum tseem tuaj yeem tshem tawm hws zoo. Hmoov zoo, tib neeg lub cev emissions dej vapor nyob rau hauv ib zaug xwb - molecule lub xeev, thaum nag thiab daus yog aggregated kua tee dej, thiab lawv qhov ntau thiab tsawg sib txawv.
