What should a professional driver do first if his truck catches fire while driving?

When a professional driver finds themselves in the unfortunate situation of their truck catching fire while driving, the first and most crucial step is to stay calm and move to the shoulder of the roadway. This action is of paramount importance for several reasons.

Firstly, moving the vehicle to the shoulder helps to ensure the safety of the driver, passengers, and other road users. By guiding the truck to a safer location away from traffic, the driver reduces the risk of a collision that could exacerbate the situation. A calm approach allows the driver to maintain focus on executing this maneuver safely and effectively.

Secondly, stopping the truck in a designated area minimizes the likelihood of causing further accidents as other vehicles navigate around the vehicle's sudden stop. Once the vehicle is safely out of the way, the driver can then assess the situation and take appropriate actions, such as calling emergency services.

The other options present responses that could either worsen the situation or fail to address the immediate necessity for safety. Therefore, the decision to remain calm and move to the shoulder represents the textbook response to managing a fire in a professional driving context.