Specification of windscreen.
This wind screen is 60 mm in diameter and fits on a 1/2 inch microphone.
Corrections to add when using Nor1451:
Frequency  Correction Uncertainty
31.5 Hz 0 dB  0.1 dB
63 Hz 0 dB  0.1 dB
125 Hz 0 dB  0.1 dB
250 Hz 0 dB  0.1 dB
500 Hz 0.05 dB  0.1 dB
1  kHz 0.15 dB 0.1 dB
2  kHz 0.3 dB; 0.2 dB
4 kHz 0.5 dB 0.2 dB
8  kHz 0.25 dB 0.3 dB
12.5  kHz -0.1 dB 0.4 dB
16  kHz -0.4 dB  0.4 dB
When theese frequency response corrections are used on the combination of wind screen type Nor1451 on microphone Nor1225 and preamplifier Nor1215 on a Nor145, it is supposed to fulfill the requirements of a type 1 sound level meter according to IEC 61672-1.
Please note that the change in frequency response due to the use of wind screens is only acceptable when the the wind screen is intact, dry and clean.