When an engine compartment fire alarm sounds or smoke is detected while driving a passenger coach, what is the driver's FIRST and most critical action?

1. Accelerate to the next city terminal to find maintenance technicians
2. Tell passengers to ignore the smoke and stay seated
3. Immediately steer to the right shoulder/breakdown lane, bring vehicle to a complete stop, engage parking brake, cut master power switch, and open passenger doors for evacuation
4. Spray bottled water into the air vents while driving