system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
In living rooms, number of air changes in one hour should be: March 2013
assistant
The correct answer is  Ans. B i.e. 2-3 Air changes per hour is a measure of how many times the air within a defined space (normally a room or house) is replaced. It is recommended that in the living rooms, there should be 2 or 3 air changes per hour; in work rooms and assemblies 4 to 6 air changes.