The 3M(tm) Noise Indicator NI-100 alerts users to potentially dangerous noise levels, helping identify areas where noise assessment may be needed to determine the need for hearing protection. Users clip the Noise Indicator to a shirt or jacket, and its LED light delivers an indication when noise levels exceed a potentially hazardous threshold. A red flashing LED means that noise levels are above 85 dBA, and hearing protection may be required. A green flashing LED means that noise levels are below 85 dBA, and hearing protection may not be necessary.