I wonder if that data is for injuries caused by chainsaws only (i.e. cuts/strikes of the saw) or all injuries reported while using a saw (i.e. limbs or whatever falling on the user while cutting). If the data includes things falling onto the users then I'm not overly surprised by the number of head injuries as I expect effective helmet use is probably less than it should be. Then again - I bet eye injuries are also considered head injuries and perhaps there are far more cases of things being thrown into eyes resulting in OSHA reports than we realize (not to mention bits of chips/dust falling from cutting above eye level and falling into eyes).