Final answer:
When a train operator pulls the emergency alarm due to heavy smoke beneath the train, the next step required by the rules is to notify the fire department or emergency services immediately in order to ensure the safety of passengers and the surrounding area.
Step-by-step explanation:
When a train operator pulls the emergency alarm due to heavy smoke beneath the train, the next step required by the rules is to notify the fire department or emergency services immediately. This is to ensure that the appropriate authorities can respond to the situation and take necessary actions to prevent any further danger or damage.
The prompt notification allows trained professionals to assess the situation, evaluate the potential risks, and take the appropriate measures to ensure the safety of passengers and the surrounding area. By promptly notifying the fire department, they can coordinate the evacuation, if necessary, and provide the necessary assistance to handle the smoke and address the potential fire hazard.