NIOSH National Institute for Occupational Safety and Health - The NIOSH Sound Level Meter App has been updated! It now works on the latest iPhone models. Download it today and always know
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![Free Sound Level Meter App from CDC's National Institute for Occupational Safety and Health | Noisy Planet Free Sound Level Meter App from CDC's National Institute for Occupational Safety and Health | Noisy Planet](https://www.noisyplanet.nidcd.nih.gov/sites/noisyplanet/files/cell-phone-cropped.jpg)