TwinCom EM2140DC-S, User Information, Page: 5 / 8

a) Introduction
The headset AK5850BS and AK5850BHS is made for use in noisy areas. It can be used together with helmet (AK5850BS,
helmet attachment) or without helmet (AK5850BHS, headband). To achieve the best attenuation, it is recommended to use
the AK5850BS/AK5850BHS together with the Offshore ear plug. The hearing protection shall be worn at all times in noisy
environments. The headset cups are made of ABS. The parts in contact with the skin (ear cushions) are made of PVC and the
helmet attachment is made of stainless steel supported by nylon plastic sleeves.
Warning : If the recommendations in this
user manual is not adhered to, the protection of this PPE may be severly impaired!
b) How to mount and adjust the headset before use
The headset shall be fitted and adjusted according to the manual to achieve maximum protection. Use of glasses, beard or
other items that can course leakage between the skin and the ear cushions may impair the attenuation.
For AK5850BS: Place the helmet attachment (1) into the slots on the helmet and put the helmet on to your head. These
earmuffs attached to head protection and/or face protection devices shall be fitted, and used only with the following
carriers/helmets: 3M G3000 (primary helmet), 3M X5500V, Auboueix IRIS 2, Petzl Vertex 1000V, MSA V-GARD 520 1000V
and Sundström SR580 (secondary helmets). The AK5850BHS headband version can be put directly over the top of your
head. For AK5850BHS: Place the headband over the center of the head. There is no mandatory left and right direction for
placement of the cups. However. To be connected to audio communication with duplex communication the microphone has to
be in the front of the mouth within a distance of 1 cm. to achieve the best noise reduction.
Adjust the moving steel rods (6) up and down until the cups are perfectly covering your ears.
Ear-muffs complying with EN 352-1 and EN 352-
3 are of “medium size range” or “small size range” or “large size range”.
“Medium size range” ear-muffs will fit the majority of wearers. “Small size range” or “large size range” ear-muffs are designed
to fit wearers for whom “medium size range” ear-muffs are not suitable.
Warning: AK5850BS is in the small, medium and
large size range (see size ranges for primary and supplementary helmet combinations under 2. g), and the AK5850BHS is for
medium and large size range.
The cups can be set in rest position by pulling them straight out from the ears. This shall only be done in areas without noise
since it will be a gap between the earmuffs and the ears. The normal position can be maintained by pressing the cups back
again towards the ears.
Adjust the microphone (3) to a position straight in front of the mouth. The distance shall not exceed 10 mm. to achieve the
optimal noise attenuation.
c) How to connect the headset to a 2-way radio
The headset can be connected to a 2-way radio by connecting the connector (4) into a PTT-unit made for the different radios.
The headset cannot be connected directly to the radio. Ask your supplier for the right PTT-unit made for each radio brand.
This headset is provided with electrical audio input. Check correct operation before use.
Warning: Do not connect or
disconnect the device to the PTT unit or turn on/off the radio while the equipment is placed over the ears. It is also important
that the interconnecting cord is not damaged.
Short cuts or other disturbance may course high noise that can damage the hearing. Warning: The electrical audio output of
this hearing protector may exceed the daily limit sound level. The usage time for maximum input voltage that corresponds to
an A-weighted equivalent diffuse-field related SPL of 82 dB(A) over 8 h is 47 seconds at 8710 mV
rms
. The A-weighted
diffuse-field related SPL for the maximum input voltage is 110 dB(A) at 8710 mV
rms
. When the earmuffs
AK5850BS/AK5850BHS are used alone the electric input level for which the mean minus one standard deviation A-weighted
diffuse-field related sound pressure level is equal to 82 dB is 336 mV
rms
. The dependence between A-weighted equivalent
diffuse-field related SPL and input voltage:
Sound Pressure Level
dB(A) Input Voltage
(mV
ms
)
70 85
75 152
80 268
85 467
90 832
95 1531
100 2661
105 4519
110 8710
d) How to connect the headset to the Offshore Ear Plug
Connect the 3.5 mm. jack plug on the Offshore ear plug into the 3.5 socket on the left
cup. This shall be done before the Offshore ear plug is placed into the ears.