Methods for acids up to 100 per cent H$d2SO$d4 for sampling oleums and for diluting and testing oleums and liquid sulphur trioxide.Cross References:BS 572BS 604BS 646BS 795BS 846BS 1647BS 1752BS 1792BS 2058BS 2586BS 3145BS 3591BS 3978BS 4123BS 4404BS 4426ISO/R 910