| THICKNESS 壁厚 | DUCT DIMENSION 风管尺寸 | REMARK 备注 |
| 0.75 mm Galvanize sheet | Size < 400 mm 单边小于400 mm SINGLE SIDE < 400 mm | ENGINEROOM 机舱 |
| 4.0 mm Steel sheet | Size ≥ 400 单边大于等于400 mm SINGLE SIDE ≥ 400 mm | ENGINEROOM 机舱 |
| 0.75 mm Galvanize sheet | Size < 500 mm 单边小于500 mm SINGLE SIDE < 500 mm | OTHERS 其他区域 |
| 4.0 mm Steel sheet | Size ≥ 500 单边大于等于500 mm SINGLE SIDE ≥ 500 mm |