As of 2015, most companies do not make HAZMAT suits specifically for kids. While Halloween shops may stock HAZMAT costumes for children, real HAZMAT suits, designed to protect an individual from dangerous chemicals, are not sized for children.
Companies that specialize in protective clothing, such as Lakeland Industries, provide sizing charts for the different brands they sell. The extra-small size is listed as fitting an individual up to 5'3" tall and weighing between 90 to 115 pounds. The average height of a 10-year-old boy in the U.S. is 4'7" and the average weight is about 70 pounds. Therefore, the average 10-year-old boy is considerably smaller than the smallest HAZMAT suit currently made by this company.