How much barium sulfate is needed for 1 square meter wall of ct room radiation protection

According to the "Basic Standard for Radiation Health Protection", the CT room must be surrounded by a solid wall made of dense cement, with a thickness of not less than 370mm, and the stucco layer is made of barium sulfate, yellow sand and cement mixed mortar, with a weight ratio of 2.5:1.5:1, and the stucco layer is not less than 30mm, and the wall needs 65kg of barium sulfate per square meter according to the proportion calculation.