Air tools must be powered by an air compressor that can provide enough pressure and volume. For many small home applications, a low-horsepower compressor can be plugged in to any available 120 volt wall socket. These compressors can go up to three horsepower or higher. Models rated at five horsepower and above are hard-wired for use in 240 volt systems. Chances are, your home applications won't require such a powerful machine, but if you aren't sure whether your home or shop can handle the load, double check the voltage requirements on the compressor and get some advice from your local power company if you need more voltage than your current electrical system can provide.