On Tue, 09 Oct 2007 17:00:13 -0000, billy
wrote:

What material can be used for shield against potentially dangerous
levels of radio waves. Lets say outside my bedroom is a radio
communication device. What material could stop the waves from
entering. Cement? Lead? How thick?

You need to fabricate one of these devices ............. immediately!

http://zapatopi.net/afdb/