"I took them outside of the building, I had several cans of compressed air (a mechanized compressor that has a water filter is better as long as it's not too high pressure). I remove the lids of the switches and "went to town" with the compressed air." One good tip with spraying anything out with compressed air is to hold a shop vac near the area you are trying to clean out, so that are you blow the dirt up off the board, it gets sucked into the vacuum, as opposed to being blown into a different part of the board. Avoid touching either to the board! Also, hold the fan still while you clean it to avoid damage.
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