(来学网)排水塑料管立管管径≥110mm时,在楼板贯穿部位设置的防火套管长度应()
  • A.
    (来学网)≥500mm
  • B.
    (来学网)≥300mm
  • C.
    (来学网)≥200mm
  • D.
    (来学网)≥50mm
正确答案:
A