To what length should the exhaust system extend beyond the occupant compartment?

The exhaust system must extend to the back of the rearmost door opening to ensure that exhaust gases are safely expelled away from the vehicle's occupant compartment. This requirement is a critical safety measure. By directing exhaust fumes away from passengers, the risk of carbon monoxide poisoning and other harmful exposure is significantly reduced. Proper placement of the exhaust system helps maintain air quality within the cabin and prevents any potential hazards related to exhaust leaks.

This specific guideline ensures that vehicles are designed with passenger safety in mind, providing a clear and defined area where exhaust can dissipate into the environment rather than being recirculated or lingering near passengers.