When openings are made in walls to connect buildings, what should always be provided?

When openings are made in walls to connect buildings, fire doors should always be provided to ensure fire protection and containment. Fire doors are specifically designed to resist the spread of fire and smoke between spaces, which is crucial in maintaining the safety of occupants and minimizing damage during a fire incident. These doors are constructed with materials that can withstand high temperatures for a specified period, allowing additional time for evacuation and potentially preventing the fire from spreading to adjoining structures.

Other options, while they may have their own specific uses, do not provide the same level of fire protection as fire doors. For example, valves may be necessary for managing utilities, windows do not contribute to preventing fire spread, and air vents could potentially allow smoke and heat to travel between buildings, which would be counterproductive in a fire situation. Thus, fire doors serve an essential function in safeguarding life and property when connecting openings between buildings are involved.