dirty protest vs stoppage

dirty protest

noun
  • A form of protest where a prisoner refuses to use the toilet and instead defecates and urinates within his or her cell. 

stoppage

noun
  • Something that forms an obstacle to continued activity; a blockage or obstruction. 

  • A pause or halt of some activity. 

How often have the words dirty protest and stoppage occurred in a corpus of books? (source: Google Ngram Viewer )