What is the maximum size for the opening of an operable window according to the guidelines?

The guidelines specify that for operable windows, the maximum size for the opening should not exceed 4 inches. This regulation is primarily established to enhance safety, particularly in preventing unintended access by small children and ensuring that objects do not accidentally fall out of the window. A limit of 4 inches allows sufficient ventilation while maintaining a degree of security and minimizing the risk of accidents.

Larger openings could pose safety hazards, which is why regulations are in place to restrict them. The chosen answer aligns with building codes and safety standards designed to protect occupants in residential and commercial properties.