4
English / USA
MS 290, MS 310, MS 390
!Warning!
Prolonged use of a power tool (or other 
machines) exposing the operator to 
vibrations may produce whitefinger 
disease (Raynaud's phenomenon) or 
carpal tunnel syndrome. 
These conditions reduce the hand's 
ability to feel and regulate temperature, 
produce numbness and burning 
sensations and may cause nerve and 
circulation damage and tissue necrosis.
All factors which contribute to white-
finger disease are not known, but cold 
weather, smoking and diseases or 
physical conditions that affect blood 
vessels and blood transport, as well as 
high vibration levels and long periods of 
exposure to vibration are mentioned as 
factors in the development of whitefinger 
disease. In order to reduce the risk of 
whitefinger disease and carpal tunnel 
syndrome, please note the following:
– Most STIHL power tools are 
available with an anti-vibration 
(“AV”) system designed to reduce 
the transmission of vibrations 
created by the machine to the 
operator's hands. An AV system is 
recommended for those persons 
using power tools on a regular or 
sustained basis.
– Wear gloves and keep your hands 
warm. Heated handles, which are 
available on some STIHL power-
heads, are recommended for cold 
weather use.
– Keep the AV system well 
maintained. A power tool with loose 
components or with damaged or 
worn AV buffers will tend to have 
higher vibration levels.
Keep the saw chain sharp. A dull 
chain will increase cutting time, and 
pressing a dull chain through wood 
will increase the vibrations 
transmitted to your hands. 
– Maintain a firm grip at all times, but 
do not squeeze the handles with 
constant, excessive pressure. Take 
frequent breaks. 
All the above-mentioned precautions do 
not guarantee that you will not sustain 
whitefinger disease or carpal tunnel 
syndrome. Therefore, continual and 
regular users should closely monitor the 
condition of their hands and fingers. If 
any of the above symptoms appear, 
seek medical advice immediately.
!Warning!
The ignition system of the STIHL unit 
produces an electromagnetic field of a 
very low intensity. This field may 
interfere with some pacemakers. To 
reduce the risk of serious or fatal injury, 
persons with a pacemaker should 
consult their physician and the 
pacemaker manufacturer before 
operating this tool.
Proper Clothing
!Warning!
To reduce the risk of injury, the operator 
should wear proper protective apparel.
Clothing must be sturdy 
and snug-fitting, but allow 
complete freedom of 
movement. Wear long 
pants made of heavy 
material to help protect 
your legs from contact with branches or 
brush. To reduce the risk of cut injuries, 
wear pants or chaps that contain pads of 
cut retardant material.
Avoid loose-fitting jackets, scarfs, 
neckties, jewelry, flared or cuffed pants, 
unconfined long hair or anything that 
could become caught on branches, 
brush or the moving parts of the unit. 
Secure hair so it is above shoulder level.
Good footing is very 
important. Wear sturdy 
boots with nonslip soles. 
Steel-toed safety boots 
are recommended.