This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Not shielded.

adj. (used especially of machinery) not protected by a shield

"He said mobile phone radiation could heat the side of the head or potentially thermoelectrically interact with the brain, while Bluetooth devices and "unshielded" headsets could convert the user's head into an effective, potentially self-harming antenna."

unprotected   

shielded    unskilled    unthreaded