I don't understand why you need a news article to do something responsible. No, there has never been a case in which it was proven that a machine with an internal combustion engine has caused a fire because of the removal of a factory installed spark arrestor. However, I think it is wise to continue using them. They don't hurt anyone by being installed, so why take the chance. If in all the years of spark arrestors, they have saved 1 or 2 fires, and somebody's home or land, then they are worth it in my opinion. After all, if it was my home or property that it had saved, I would be very thankful. In theory it makes sense to me why they work, albeit old technology. Carbon buildup on the head, exhaust valve, or somewhere close to the head can retain enough heat to be smoldering as it is thrown from the engine, especially on a red hot motor. Once that little piece of hot stuff hits a dry leaf, I could see it igniting. The spark arrestor is merely a screen to slow down that little fire starter, and gives it time to cool before being thrown to the ground. Certainly, most 4 stroke engines today run so clean and efficiently that you may never have that buildup that could end up 'sparking', but why take the chance? Just my two cents. :ride: