What gases can enter the cabin, causing a failure of the floor pan during inspection?

Exhaust gases are a significant concern during vehicle inspections as they can enter the cabin through various means, such as leaks in the exhaust system or improperly sealed areas. These gases include harmful substances like carbon monoxide, nitrogen oxides, and particulate matter, which can not only compromise the vehicle’s structural integrity if they contribute to corrosion of the floor pan but also pose severe health risks to the occupants.

Identifying the presence of exhaust gases during an inspection is crucial, as they can lead to a variety of issues, including safety hazards due to toxicity and potential failure of vital components such as the floor pan due to ongoing corrosive effects. This specific focus on exhaust underscores the importance of maintaining a vehicle's exhaust system, ensuring not just performance, but also passenger safety and vehicle longevity.

In contrast, while other gases mentioned may have their own set of issues, they do not directly relate to the failure of the floor pan during inspection as exhaust gases do.