What should be used to cover air inlets from outside the building serving residential occupancies?

The appropriate cover for air inlets from outside a building serving residential occupancies is a screen that has openings between ¼ to ½ inch. This type of screen allows for the adequate passage of air, which is crucial for ventilation, while also preventing the entry of larger debris, insects, and small animals. The specified size of the screen openings is effective in balancing airflow with protection, maintaining the efficiency of HVAC systems and ensuring indoor air quality.

In residential settings, controlling what enters through air inlets is important for maintaining comfort and safety. A screen that has been sized within that specific range strikes a good balance between being effective and ensuring that airflow is not overly restricted.

Other options like wire mesh could be too fine or too coarse depending on the size of the mesh, plastic covers might not allow for any ventilation at all, and wooden slats might not provide sufficient airflow combined with adequate filtration against unwanted intrusions. Therefore, the screen with ¼ to ½ openings is specifically designed to meet the needs for both protection and ventilation in a residential context.