Poisonous fumes can enter a cab due to: Question Poisonous fumes can enter a cab due to: Answers A defective exhaust system. Using the wrong type of fuel. A lack of oil in the engine. Explanation A faulty exhaust system is a serious safety hazard. It may allow poisonous fumes to enter the vehicle's cab or sleeper berth. This questions appears in the following tests: Kentucky Class A Knowledge Test Louisiana Tank Maryland Class B Knowledge Test Montana Class B Knowledge Test Nebraska Tank North Carolina Class A Knowledge Test North Carolina Passenger Oklahoma Passenger Oregon Class B Knowledge Test Rhode Island Double Tennessee Class A Knowledge Test Vermont Passenger Washington Class A Knowledge Test Washington Class A Knowledge Test
