How is brake fluid typically assessed?

Assessing brake fluid is important for maintaining the hydraulic braking system's efficiency and safety. Brake fluid is typically evaluated by checking its moisture content and boiling point. Over time, brake fluid can absorb moisture from the air, which lowers the boiling point and can lead to brake fade, where the brakes become less effective under heavy use due to vaporization of the fluid.

Measuring moisture content involves using a brake fluid tester or a refractometer, allowing technicians to determine if the fluid is still within acceptable levels for safe operation. Likewise, testing the boiling point provides insight into whether the fluid has degraded, as a lower boiling point indicates that the fluid is likely contaminated.

Other options, such as measuring engine temperature, inspecting brake pads' thickness, or analyzing brake pedal resistance, do not provide relevant information about the condition of the brake fluid specifically. Therefore, checking moisture content and boiling point is the correct approach to assessing brake fluid health and ensuring optimum brake performance.