Limitation of liquid penetration testing method : This process requires elaborate surface cleaning. Surface cleaning shall be properly done otherwise there will not show any indication. Processing is time consuming. The process has temperature limitations. 5 degree Cent. to 52 degree cent. For testing at high temp special penetrant materials are required. Requires careful processing. Does not indicate the size of the discontinuities. Difficult to test porous materials & rough surface. Requires post cleaning.