(Equivalent Test Methods: IP 303 and ISO 3679)
EXPLANATION
These test methods cover procedures for the determination of the flash point by a small scale closed tester. The procedures may be used to determine the actual flash point temperature of a sample or whether a product will or will not flash at a specified temperature (flash/no flash).
TEST SUMMARY
Method A: Flash/No Flash Test - A portion of a sample is introduced by a syringe into the cup of the selected apparatus that is set and maintained at the specified temperature. After a specific time a test flame is applied and an observation made as to whether or not a flash occurred.
Method B: Finite (or Actual) Flash Point - A portion of a sample is introduced into the cup of the selected apparatus that is maintained at the expected flash point. After a specified time, a test flame is applied and an observation made as to whether or not a flash occurred.
The portion is removed from the cup, the cup cleaned, and the cup temperature adjusted 9 ° F (5 ° C) lower or higher depending on whether or not a flash occurred previously. A fresh portion is introduced and tested. This procedure is repeated until the flash point is established within 9 ° F (5 ° C).
The procedure is then repeated at 2 ° F (1 ° C) intervals until the flash point is determined to the nearest 2 ° F (1 ° C). If improved accuracy is desired, the procedure is repeated at 1 ° F (0.5° C) intervals until the flash point is determined to the nearest 1 ° F (0.5° C).
TEST PRECISION
Where M is the mean of the two results.