What type of ventilation must be provided in confined spaces for proper combustion of heaters?

In confined spaces where heaters are present, proper combustion requires a consistent supply of air, which is why general mechanical ventilation is necessary. This type of ventilation uses fans and ductwork to circulate air, ensuring that there is enough fresh air for the combustion process to occur safely and efficiently.

While natural ventilation relies on passive air flow through openings, it may not provide the required air exchange rates in all conditions, especially if the openings are insufficient or if external conditions limit air movement. Open air ventilation is not a specific term used in building codes to describe a type of effective ventilation system. Controlled ventilation implies a system that can be adjusted based on specific needs, though it does not guarantee that adequate air is provided for combustion as reliably as general mechanical ventilation does.

General mechanical ventilation is regarded as the most effective method for ensuring a constant air supply, which is crucial to prevent potential hazards such as carbon monoxide buildup or inadequate combustion. Therefore, in the context of ensuring safety and efficiency in confined spaces with heating systems, this type of ventilation is essential.