What are the performance criteria for clean agents in terms of ozone depletion potential (ODP) and global warming potential (GWP)?
Clean agents used in fire suppression systems are evaluated based on their environmental impact, primarily focusing on Ozone Depletion Potential (ODP) and Global Warming Potential (GWP). Ozone Depletion Potential (ODP) is a relative measure of the degree to which a chemical can deplete the ozone layer in the stratosphere. The ODP of a chemical is measured relative to the ODP of CFC-11, which is assigned an ODP of 1. Clean agents should ideally have an ODP of zero, indicating that they do not contribute to ozone depletion. Halon fire suppressants, which were widely used in the past, had high ODP values and were phased out due to their harmful effects on the ozone layer. Global Warming Potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere compared to carbon dioxide (CO2) over a specific time period, typically 100 years. The GWP of CO2 is assigned a value of 1. Clean agents should have a low GWP to minimize their contribution to global warming. The lower the GWP, the less impact the agent has on climate change. For example, FM-200 has a GWP of 3140, while Novec 1230 has a GWP of 1. These values indicate that Novec 1230 has a significantly lower impact on global warming than FM-200. Regulatory agencies, such as the U.S. Environmental Protection Agency (EPA), set limits on the ODP and GWP of fire suppression agents. Clean agents must meet these regulatory requirements to be approved for use. The trend in fire suppression is towards using agents with zero ODP and low GWP to minimize environmental impact. Therefore, when selecting a clean agent, it is crucial to consider both its ODP and GWP to ensure that it meets environmental regulations and minimizes its contribution to ozone depletion and global warming.