Maybe.
I've never gone through the list of requirements for approving something under the FCC guidelines, but I wouldn't be surprised if there's something in there that says that at distance x the generated RF from the device (e.g. through the psu, chips on the board, out of the antenna, etc..) can't be more than y in any direction.
There's also the guidelines specific to ISM bands.
Google EMC (electromagnetic compatibility) for getting an understanding that your device may not be 'harmful' to other devices, but also that your device can tolerate a certain rf noise environment from other devices. You may even *want* to put your project in a metal can if your device is highly susceptible to outside noise.
If you're using a plastic enclosure, investigate 'metallic paint' (similar to what you sometimes see inside laptops, not sure of the proper name of the substance) to provide an rf shield on the inside of your enclosure. That could be all you need.
