Typical parts of a chain saw are identified in the following picture.
OSHA REQUIRES that the chain saw have the parts identified in bold text.
[29 CFR 1910.266(e)(1)
Chain saws placed into service after February 9, 1995 must also meet the requirements of ANSI B175.1-1991, Safety Requirements for
Gasoline Powered Chain Saws.
1 Chain catcher to prevent a broken or dislodged chain from
Checklist for Field Use: Chain Saw
striking the logger.
4 Decompression valve
5-7 Anti-vibration handle system is recommended by
OSHA to limit ergonomic stress to the
6 Hand guard
8 Muffler to reduce engine noise.
9 Chain brake to stop the chain if kickback occurs, if the
saw was placed into service after February 9, 1995.
10 Throttle which will stop the chain when pressure on the
throttle is released.
11 Throttle interlock which prevents the throttle from
activating until the interlock is depressed.