Sulfuric acid at workplacesapplicability of the new Indicative Occupational Exposure Limit Value (IOELV) to thoracic particlesPresented at the Seventh International Symposium on Modern Principles on Air Monitoring & Biomonitoring, June 1923, Loen, Norway

• Main Authors: Breuer, Dietmar, Heckmann, Petra, Gusbeth, Krista, Schwab, Gregoria, Blaskowitz, Morten, Moritz, Andreas
• Format: Article
• Language: English
• ISSN: 1464-0325; 1464-0333
• DOI: 10.1039/c2em10659k

Until 2009, the limit values for airborne sulfuric acid in Europe were based on the inhalable particle fraction ( e.g. MAK (Maximum allowed concentration at workplace) value 0.1 mg m 3 as the inhalable fraction). With the publication of the Commission Directive 2009/161/EU, an Indicative Occupational Exposure Limit Value (IOELV) of 0.05 mg m 3 for sulfuric acid aerosols was based for the first time on the thoracic particle fraction. To permit a comparison of the measured values for the inhalable fraction with those of the thoracic fraction and to quantify the thoracic fraction, a cyclone was fabricated out of sulfuric-acid-resistant stainless steel that achieves suitable collection characteristics (PM 10 ) at a flow rate of 5.34 L min 1 . 49 measurements were carried out in parallel in 21 companies. At concentrations well below the IOELV, there is little difference between the thoracic and inhalable particle concentrations. At higher concentrations (>0.1 mg m 3 inhalable aerosol), larger droplets have a marked effect on the measured values and the thoracic fraction accounts for only 32.1 12.5% of the inhalable fraction. The EU's IOELV and the proposal of the MAK Commission therefore provide a comparable level of protection. In the transposition of the IOELV into national law, an air limit of 0.1 mg m 3 could therefore be implemented for the inhalable fraction. The paper presents a first comprehensive study of sulfuric acid measurements at workplaces using a high flow thoracic sampler.