Qhov sib txawv ntawm qhov hluav taws kub tsis kam ntawm qhov rooj hluav taws: lub qhov rooj hluav taws tau muab faib ua A, B, C, uas yog qhov kev tiv thaiv hluav taws kub ntawm lub qhov rooj hluav taws, uas yog, lub sijhawm hluav taws kub, tus qauv tam sim no yog kev tiv thaiv hluav taws. lub sij hawm tsis tsawg tshaj 1.5 teev, chav kawm B tsis tsawg tshaj 1.0 teev, chav kawm C tsis tsawg tshaj 0.6 teev.

hom qhov rooj yog dab tsi,hluav taws kub qhov rooj vs qhov rooj qub, hluav taws kub ntsuas qhov rooj ncaws phaj,b daim ntawv lo qhov rooj hluav taws, c daim ntawv lo hluav taws qhov rooj,

hluav taws kub resistant qhov rooj manufacturers,hom qhov rooj yog dab tsi,fireproof lub qhov rooj, hluav taws pov thawj qhov rooj khoom,b daim ntawv lo qhov rooj hluav taws ntsuas,Hluav taws kub ntsuas qhov rooj thickness, steel qhov rooj x, Thaum muaj xwm ceev tawm qhov rooj siv, hluav taws nyob qhov rooj 90 feeb,c daim ntawv lo hluav taws qhov rooj,

ntoo fireproof qhov rooj,c daim ntawv lo hluav taws qhov rooj,siv qhov rooj thaum muaj xwm ceev, hluav taws kub ntsuas qhov rooj ul, hluav taws kub ntsuas qhov rooj nyob