What is the safest route in case of gas detection in a furnace?

Evacuating the area and contacting professionals is the safest route in the event of gas detection in a furnace. This approach prioritizes the safety of individuals present by removing them from a potentially dangerous situation where a gas leak could lead to fire or explosion risks. Emergency services or qualified technicians have the expertise and equipment necessary to handle gas leaks safely, ensuring that the situation is assessed and resolved without danger to those who may not have the specialized training.

While ensuring proper ventilation is important in some contexts, it does not address the immediate need to remove people from a hazardous environment when gas is detected. Turning off the main supply and checking the gas lines carries inherent risks, as this could expose the individual to the gas and further complicate the situation. Monitoring the situation from outside does not provide an effective solution either; while staying at a safe distance is fundamental, it does not actively resolve the issue, and the focus should be on obtaining professional assistance.

Overall, evacuating and contacting professionals is a comprehensive response that safeguards lives first and foremost, while also ensuring that trained experts can handle the technical aspects of the gas detection appropriately.