double wrapping

Question

kevod harav "I hear" that in going to the bathroom with seforim or tashmeshei kedusah, it is not enough for it to be in a pocket or a suitcase. it has to be wrapped again, and maybe twice? what is thehalacha? 2. heating up food in a microwave that is used for treif, like at work,, how much must our food be wrapped, once double wrapped???thank you jh