You press the brake pedal of your motor vehicle fully down. What is the maximum safe decrease of pressure in the braking system if the air tanks are full?

The correct answer is 0.7 bar. In German traffic regulations for vehicles with compressed air braking systems, when you press the brake pedal fully with fully charged air tanks, the pressure drop in the system should not exceed 0.7 bar. This limit ensures there is enough remaining air pressure in the system for safe braking, preventing brake failure. Exceeding this value may indicate leaks or faulty components, which is a safety risk. Knowing this value is important for safety checks and inspections on vehicles with air brakes.