Last week E-116 responded to a mid 30's male who had cut off his hand with a skill saw. The house we stop at had no signs of anyone home or any form of construction taking place. My Captain and I decide maybe the person is inside and passed out so we go ahead and make entry ourselves. Just as we get inside a 70 year old man walks around the corner and asks if something is wrong. We ask him if he had cut off his hand . He says "no everything here is just fine, you boys must have the wrong address". He was right and it sucked. So we get the right address now from dispatch and we arrive at the corrected address to find a man sitting on the front lawn holding his hand. We looked at the hand and the dog was chewing on it. (just kidding about the dog part). The man never cut his hand completely off but it was filleted open pretty good. We rapped it up and took care of the hand and sent the man to the hospital with M-116. The engine crew stayed at the house to help the Grandma with the kids and clean up the bloody mess in the house. We later discovered that the gentleman was never doing construction, he was trimming the lawn and ran out of string. He couldn't find anything to cut the new string with to refill the trimmer so he turned on his table saw to cut the string. Ya you guessed it, the table saw pulled his hand right in. He's very lucky it didn't pull his whole body in. So lesson learned. Use a knife or pair of cutters to cut trimmer line NOT A SAW.