Chemical and physical properties, and tolerances on dimensions and defects, for refractories of not less than 93% silica.Cross References:BS 1902:Section 2.1BS 1902:Section 3.5BS 1902:Section 3.8BS 1902:Section 3.11BS 1902:Section 3.13BS 1902:Section 4.3BS 1902:Section 4.8BS 1902:Section 4.9BS 1902:Section 5.10BS 1902:Section 9.2BS 3446BS 6065BS 6434BS 6886