Abstract
Pion attenuation following nucleon decay within a nucleus is examined. It is found that predictions of pion survival may be made by use of established phenomenology. The reduction in pion flux is a factor of 2 for C12 or O16. This implies that the number of observable μ+'s for a water source would be 0.55 times that from a free-nucleon mixture. For the π0e+ mode the probability of survival as a correlated pair is 0.33.