Normalized impact noise level Ln 

Definition and scope

Determination of transmission of impact sound of floors excited by a standard tapping machine.

The measurement shall be performed in a laboratory.

Evaluation method according to NF EN ISO 10140-1 and 3  

Expression of results: Calculation of the single index Ln weighted according to DIN EN ISO 717-2

Values of Ln in third octave bands between 100 and 3150 Hz accounted for, accuracy of 1/10th of a dB.

Vertical displacement of a reference curve by 1 dB break until the sum of adverse deviations is the largest while remaining less than or equal to 32 dB.

Ln, w is the value given by while the reference curve at 500 Hz

Example Ln test result