NIOSH Sound Level Meter (SLM) App

The National Institute for Occupational Safety and Health (NIOSH) is pleased to announce the availability of a new mobile application (app) for iOS devices that can measure sound levels in the workplace. The app called the NIOSH Sound Level Meter (SLM) app can help promote better hearing health and prevention efforts at construction worksites by acquiring and displaying real-time noise exposure data when occupational safety and health professionals are not readily available. The NIOSH SLM app is free, easy to use, and can give any user immediate feedback about sound levels and noise exposure.


The NIOSH SLM app provides a readout of the sound level in the workplace using the smartphone’s built-in microphone, or preferably, an external calibrated microphone (see details on our NIOSH Science Blog).  It reports the instantaneous sound level, equivalent sound level, time-weighted average, and noise dose based on NIOSH and OSHA limits (user selectable). The app also contains basic information about noise and hearing loss prevention. This app could be particularly helpful to occupational safety and health trainers because they can use the NIOSH SLM app to raise construction apprentices’ awareness of noise hazards and the need to protect their hearing. In addition, the app allows users to save and share measurement data with others through the smartphone’s communication and media features. 


For additional information, please visit the app page at: or contact CAPT Chucri (Chuck) A. Kardous, M.S., P.E. at  To install the NIOSH Sound Level Meter app on your iOS device, visit the iTunes app store.