3M Peltor ComTac VII MT14H41A-300NA, User Manual

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LABORATORY ATTENUATION
U.S. EPA specifies the NRR as the measure of hearing protector noise reduction. However, 3M makes no warranties as to the
suitability of the NRR for this purpose. 3M strongly recommends personal fit testing of hearing protectors. Research suggests
that users may receive less noise reduction than indicated by the attenuation label value(s) on the packaging due to variation in
fit, fitting skill, and motivation of the user. Refer to applicable regulations for guidance on how to adjust attenuation label values.
It is recommended that the NRR be reduced by 50% to better estimate typical protection.
The attenuation rating (NRR) was obtained with the device powered off.
STANDARD ANSI S3.19-1974
MT14H41A-300NA
A:A Headband with foam cushion
A:1 Frequency (Hz) (ƒ) 125 250 500 1000 2000 3150 4000 6300 8000 NRR CSA
Class
A:2 Mean attenuation (dB) (Mf)
14.0 19.4 27.9 32.3 31.7 39.7 44.5 40.1 41.0
22
A:3 Standard deviation (dB) (sf)
2.7 3.2 2.6 2.1 2.8 3.6 3.4 2.6 2.2
B
MT14H41A-300NA with HY80
A:B Headband with gel cushion
A:1 Frequency (Hz) (ƒ) 125 250 500 1000 2000 3150 4000 6300 8000 NRR CSA
Class
A:2 Mean attenuation (dB) (Mf)
14.9 18.5 27.1 34.5 34.1 39.8 42.1 40.9 40.1
23
A:3 Standard deviation (dB) (sf)
2.6 2.4 2.5 2.8 2.5 3.2 3.4 2.7 2.9
A
MT14H41A-300NA
A:C Helmet attachment with foam cushion on
3M Combat High Cut Ballistic Helmet C105HC
A:1 Frequency (Hz) (ƒ) 125 250 500 1000 2000 3150 4000 6300 8000 NRR CSA
Class
A:2 Mean attenuation (dB) (Mf)
13.1 19.2 27.0 31.0 31.4 39.0 43.1 42.0 42.2
22
A:3 Standard deviation (dB) (sf)
2.9 2.7 2.2 2.0 2.8 2.9 3.2 3.0 3.3
B
MT14H41A-300NA with HY80
A:D Helmet attachment with gel cushion on
3M Combat High Cut Ballistic Helmet C105HC
A:1 Frequency (Hz) (ƒ) 125 250 500 1000 2000 3150 4000 6300 8000 NRR CSA
Class
A:2 Mean attenuation (dB) (Mf)
13.7 17.5 25.8 34.2 34.9 39.7 42.3 41.9 40.8
22
A:3 Standard deviation (dB) (sf)
2.8 2.5 2.2 2.1 2.3 2.8 3.8 2.9 2.3
A