Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Noise Criterion vs. Noise Rating and dB(A)

Comparing Noise Criterion (NC, NCB, RNC) to Noise Rating (NR) and dB(A).

Noise Criterion - NC - were established in U.S. for rating indoor noise, noise from air-conditioning equipment etc.

In Europe it is common to use Noise Rating Curves - NR.

dB(A) - LA - is a weighted method compensating for the human hearing of sound pressure at different frequencies.

Choosing appropriate noise criteria is important when specifying acceptable levels of noise. Most organizations use a particular index based upon practical experience. Recommended maximum noise levels for different types of rooms and standards are indicated in the table below

Noise Criterion vs. Noise Rating and dB(A)
Type of Room - OccupancyMaximum Level (dB)
Noise Criterion
- NC, NCB, RNC -		Noise Rating
- NR -		dB(A)RC
Very quiet Concert and opera halls, recording studios, theaters, etc. 10 - 20 20 25 - 30 20
Private bedrooms, live theaters, television and radio studios, conference and lecture rooms, cathedrals and large churches, libraries, etc. 20 - 25 25 25 - 30 25
Private living rooms, board rooms, conference and lecture rooms, hotel bedrooms 30 - 40 30 30 - 35 30
Quiet Public rooms in hotels, small offices classrooms, courtrooms 30 - 40 35 40 - 45 35
Moderate noisy Drawing offices, toilets, bathrooms, reception areas, lobbies, corridors, department stores, etc. 35 - 45 40 45 - 55 40
Noisy Kitchens in hospitals and hotels, laundry rooms, computer rooms, canteens, supermarkets, office landscape, etc. 40 - 50 45 45 - 55 45

Related Topics

  • Acoustics

    Room acoustics and acoustic properties. decibel A, B and C calculations. Noise Rating (NR) curves. Sound transmission through walls. Calculate sound pressure, sound intensity and sound attenuation.

Related Documents

Search

Search is the most efficient way to navigate the Engineering ToolBox.

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

Translate this Page

Translate this page to Your Own Language .

About the Engineering ToolBox!

Privacy Policy

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

Citation

This page can be cited as

  • The Engineering ToolBox (2004). Noise Criterion vs. Noise Rating and dB(A). [online] Available at: https://www.engineeringtoolbox.com/noise-criteria-d_726.html [Accessed Day Month Year].

Modify the access date according your visit.

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter

















































9.26.9

.