When this analysis was done for each of the locations individually, the location with the most volunteers enrolled in the study (the prebake smelter) appeared to be where the greatest reductions were seen. The smelter that had experienced work slowdowns due to the economic downturn had a lower rate of daily noise dose readings in excess of the 85 dBA or the 90 dBA levels. The third location (turbine component factory) had a smaller number of enrolled individuals, and there was no clear downward trend of daily noise doses exceeding 85 dBA or 90 dBA at that location. At that facility, the noise overexposures appeared to be driven by a small number of individuals working near a loud noise source.