Paragraph 8.6.1 Extraneous noise
The average sound pressure level over the measuring surface, calculated in accordance with the method described in 8.1, shall be corrected, if necessary, to take account of the extraneous noise determined in accordance with the method described in 8.2. The correction K1, in dB, which shall be subtracted from the average sound pressure level over the measuring surface is given in Table II.
Table II
| Difference (in dB) between the sound pressure level calculated when the sound source is operating and the sound pressure level due to extraneous noise alone | Correction K1 in dB |
|---|---|
| less than 6 | no valid measurement |
| 6 | 1.0 |
| 7 | 1.0 |
| 8 | 1.0 |
| 9 | 0.5 |
| 10 | 0.5 |
| more than 10 | no correction |