What does the IMC require for the ventilation of buildings?

The International Mechanical Code (IMC) establishes guidelines for the ventilation of buildings to ensure a healthy indoor environment. Ventilation requirements are closely tied to the occupancy of a space. This means that the amount and type of ventilation needed should be tailored according to the specific uses of each area within a building and the number of occupants.

For instance, certain areas such as restrooms, kitchens, and assembly areas have higher occupancy levels and generate specific contaminant loads. Consequently, these areas will require more robust ventilation solutions compared to less frequently occupied spaces like storage rooms.

By designing the ventilation system based on occupancy, the IMC aims to promote health, safety, and comfort by providing adequate fresh air while also managing energy efficiency. This flexibility ensures that buildings can effectively meet the unique needs of their occupants, leading to better indoor air quality.

In contrast, options that limit ventilation types—such as seasonal, mechanical only, or natural only—do not fully address the varying needs dictated by different occupancy scenarios within a building, and therefore would not comply with the comprehensive requirements of the IMC.