Buildings may be as simple as a lone roof providing shelter from the rain for a single occupant, or as complex as a hospital regulating temperature, air flow, light, gas content, bacteria movement, particle flow, pressure, and people movement and activities. | Buildings may be as simple as a lone roof providing shelter from the rain for a single occupant, or as complex as a hospital regulating temperature, air flow, light, gas content, bacteria movement, particle flow, pressure, and people movement and activities. |