Brake fluids used in 159 passenger cars, produced in 1998-2017 with a varied mileage were studied for b.p. Fluids with b.p. above 180 degrees C (55.4%), in the range of 180-155 degrees C (33.3%) and less than 155 degrees C (11.3%) were qualified as materials for further exploitation, short-term use or decommissioning, resp. The b.p. values of brake fluids decreased with an increase of the age of cars and their annual and total mileages.