Which material has a higher heat release rate (HRR) compared to others?

The heat release rate (HRR) is a measure of the energy released during combustion of a material and is a critical factor in fire dynamics. Among the materials listed, polyethylene, which is a plastic commonly used in furniture and various household items, typically has a higher HRR compared to gasoline, a Christmas tree, or a wooden table.

Polyethylene has a significantly high energy content and burns quickly and intensely, leading to a rapid increase in temperature and a high HRR when involved in a fire. This characteristic means that when compared to gasoline, which has a high HRR as well but is in liquid form, polyethylene can also release substantial amounts of heat, especially in solid form where it can ignite and contribute to sustained combustion.

In contrast, a Christmas tree, while flammable, has a different structure and composition which generally results in a lower HRR relative to polyethylene during combustion. Wood, such as that used in a wooden table, also burns but typically does so at a slower rate compared to the high-energy release of polyethylene.

Therefore, recognizing the combustion characteristics of different materials provides insight into why polyethylene chair materials exhibit a higher heat release rate during combustion compared to the other options listed.