Does aluminum foil or a reflective plastic emergency blanket block radiation in case of a radiation leak or dirty bomb?

Dirty Bomb: In the case of a dirty bomb the CDC recommends that you cover your mouth and nose with a cloth and immediately enter a building. Remove the cloth and your clothing and immediately wash yourself with soap and water. Seal the clothing in a plastic bag if possible before showering and do not touch it after you shower. Listen to local radio stations for instructions. http://tinyurl.com/jav3zmu

Survival: 3 questions answered: 1) Decent survival food should have similar nutrition as regular food, so insulin requirements should be similar. 2) Poop and pee can go into sealable plastic bags/drums for a while, but consider chemical toilets (porta-potty). 3) A large amount of radiation in the air will get you no matter what. Whole body decontamination suits will limit contact exposure.