is the engine harmful because it could expand due to pressure

Question: is the engine harmful because it could expand due to pressure
- Keywords:
  dangerous,
  engine,
  expand,
  harmful,
  pressure
Asked by milleh to Charlie on 15 Mar 2011.
- Charlie Ryan answered on 15 Mar 2011:
  
  nice Q thanks milleh.
  No it isn’t harmful but it is something we have to consider when we are doing the testing. For example our propellent liquid often has air bubbles in it. If these air bubbles were still there when it was put into space the bubbles would expand, splurting liquid everywhere!
  To remove these bubles we put the propellent in a vacuum chamber, and suck them out!

Question: is the engine harmful because it could expand due to pressure