Knauf Fire and Water Resistant Gypsum Boards have been evaluated to meet the requirement for Type X (Special Fire-Resistant) compliant board as defined by ASTM C1396. These boards are specifically designed for use in areas where fire and moisture protection is required. Field of Application: Knauf Type X Fire and Water Resistant Gypsum Boards (GB-WRTX) are high performance gypsum boards used as the cladding component of drywall constructions in humid areas such as:Fire Rated Partition or Ceilings of Kitchens / Bathrooms Fire Rated Shaftwalls in humid areas.