Hearl, FrankHryniewicz, OlgierdStudzinski, JanRomaniuk, Maciej2019-09-162019-09-162007https://dl.gi.de/handle/20.500.12116/27681Occupational hygienists have used exposure limits as a trigger for remedial action, a target for engineering control efforts, and as a tool in selecting appropriate personal protective equipment. The limits have often been set in the absence of complete scientific understanding and with significant uncertainties. The formal processes for modifying existing limits or setting new limits are often controversial and slow to respond to changing conditions, such as the introduction of new materials or exposure situations, e.g. mixtures. Hygienists often use professional judgement when dealing with situations where exposure limits are inadequate or non-existent, for example for biological agents and nanomaterials. New systematic approaches to exposure control have been devised that use gross properties, qualitative exposure assessment, and categorical risk phrases to guide in the selection of appropriate control strategies. Applying these techniques along with appropriate professional judgement can be used to protect workers from potentially harmful exposures in the absence of complete scientific information.Text/Conference Paper