Class A foam is typically used in which concentration range?

Class A foam is used in a concentration range of 0.3-0.6% because this specific concentration is effective for reducing the surface tension of water, which allows it to penetrate and wet Class A materials, such as wood and other combustible solids. This property enhances the foam’s ability to cool the burning material and suppress the fire by creating a barrier that cuts off the oxygen supply.

When using foam in firefighting, it is crucial to adhere to this concentration range to maintain its effectiveness. A lower concentration may not provide sufficient coverage or suppression capability, while a higher concentration could be unnecessarily wasteful or may lead to other operational issues. Therefore, employing Class A foam within the 0.3-0.6% range is optimal for effective fire suppression tactics.