Pensky-Martens closed tester - apparatus used in determining the flash point of fuel oils and cutback asphalt under conditions prescribed by test method ASTM D 93. The test sample is slowly heated in a closed cup, at a specified constant rate, with continual stirring. A small flame is introduced into the cup at specified intervals through shuttered openings. The lowest temperature at which the vapors above the sample briefly ignite is the flash point. See Tag closed tester.