Lenovo S5000 Tablet - Manual (Page 7)

Important safety and handling information
hearing loss. Adjustment of the equalizer to maximum increases the
earphone and headphone output voltage and the sound pressure level.
Therefore, to protect your hearing, adjust the equalizer to an appropriate
level.
Excessive use of headphones or earphones for a long period of time at high
volume can be dangerous if the output of the headphone or earphone
connectors do not comply with specifications of EN 50332-2.
The headphone output connector of your tablet complies with EN 50332-2
Sub clause 7. This specification limits the tablet's maximum wide band true
RMS output voltage to 150 mV. To help protect against hearing loss, ensure
that the headphones or earphones you use also comply with EN 50332-2
(Clause 7 limits) for a wide band characteristic voltage of 75 mV. Using
headphones that do not comply with EN 50332-2 can be dangerous due to
excessive sound pressure levels.
If your tablet came with headphones or earphones in the package, as a set,
the combination of the headphones or earphones and the tablet already
complies with the specifications of EN 50332-1. If different headphones or
earphones are used, ensure that they comply with EN 50332-1 (Clause 6.5
Limitation Values). Using headphones that do not comply with EN 50332-1
can be dangerous due to excessive sound pressure levels.
Sound Pressure Warning statement
For the device which tests accordance to EN 60950-1:
2006+A11:2009:+A1:2010+A12:2011, it is mandatory to perform audio tests
for EN50332.
This device have been tested to comply with the Sound Pressure Level
requirement laid down in the applicable EN 50332-1and/or EN 50332-2
standards. Permanent hearing loss may occur if earphones or headphones
are used at high volume for prolonged periods of time.