Liquid Penetrant Testing (LPT) is a non-destructive testing (NDT) technique used to detect surface flaws that may not be detectable to the naked eye under standard lighting conditions. Liquid penetrant testing is typically used for non-magnetic metals to reveal surface flaws and in some cases plastics. Penetrant testing is one of the simplest and most economical non-destructive testing techniques. Additionally, it requires the least investment in personnel in terms of formal