1.1 This test method covers relative stability of middle distillate fuels under high temperature aging conditions with limited air exposure. This test method is suitable for all No. 1 and No. 2 grades in Specifications D 396, D 975, D 2880, and D 3699 and for grades DMX and DMA in Specification D 2069. It is also suitable for similar fuels meeting other specifications.1.2 This test method is not suitable for fuels whose flash point, as determined by Test Methods D 56, D 93, or D 3828,