An additional aspect of vehicular environmental pollution is noise emission. The noise emission limits enforced by law, are partially shown in the figure. The frequency-evaluated sound-pressure level in dB(A) in a definite driving condition (accelerated drive-by) serves as a measure for the disturbance resulting from noise.
One final selection criterion that still belong to the area of environmental influences is the vibratory characteristic of vehicle propulsion. Besides the noise strain, vibrations of the engine that are too strong can annoy the vehicle's passengers and cause material fatigue of the power train components or the engine mounts.
Finally, the assessment criteria can be summarized as follows:
Operating behavior
Driving characteristic
Start-up behavior
Control behavior and startability
Economy
Specific energy or fuel costs
Specific production costs
Power-to-weight ratio and power-to-volume ratio
Maintenance costs
Capability to use multiple fuels
Durability and reliability
Environmental influences
Exhaust emission
Noise emission
Vibration behavior