Can radiation penetrate a Faraday cage?

That depends on the radiation. A Faraday cage works only on electromagnetic radiation below some limiting frequency. Alpha and beta radiation are probably blocked before ever getting to the cage. read more

The Faraday cage is effective for electromagnetic radiation with wavelength significantly larger than atomic spacing for a box type ‘cage’. So gamma radiation could penetrate the cage. Very long wavelength radiation may be able to penetrate the cage owing to the effect of the long ‘skin depth’ for this type of radiation. read more

The Faraday Cage (named after its discoverer) means that the electric charge on a conductor sits on the outer surface of it. Therefore, no electrostatic field is present within the conductor FARADAY CAGE – RADIOWAVES. PURPOSE: To demonstrate that radio waves cannot penetrate a Faraday cage. read more