Not tree related - but

[Steve NW WI]

Guy was killed locally when a cutoff saw kicked back and struck him in the neck while working on a water main project: Pioneer Press Article

Sounds like this company recently had some trouble with OSHA, but it was related to excavating techniques, and not so much equipment related.

 

[hazard]

This same thing happened on a highway project I designed in ####eyville Wi in 2006. Cutting a concrete pipe in the trench and saw kicked back. By the time he was found it was to late

Scary stuff
Chris