EXPOSURE TO SULFURIC-ACID AND SULFUR-DIOXIDE IN THE MANUFACTURING OF TITANIUM-DIOXIDE

An assessment of exposure to sulphuric acid and sulphur dioxide was performed in the French titanium dioxide manufacturing industry. The three plants use the sulphuric acid process. with potential exposure mainly to sulphur dioxide and sulphuric acid. The exposures found were below the French limit values, except for some employees using the Moore filtration process in one plant. For sulphuric acid sampling, a comparison was made between thoracic particulate mass and inhalable particulate mass, from samples taken with a Marple cascade impactor. This comparison shows that the suggested new limit value (0.1 mg m-3 in thoracic particulate mass) would be much more severe than the present one (1.0 mg m-3 with no restriction as to the droplet size).