I think it’s safe to expose yourself to the Smart Key’s rays.
It uses infrared, not X-rays. I mean it’s like exposing yourself to the sun. Plus, all the phones, computers and new gadgets these days use wireless technology (Bluetooth, infrared, Wi-Fi, etc.) to connect with each other. So if you’re not gonna get cancer from your Smart Key (or cell phone), you’d get it from all the waves flowing around you everywhere you turn.