When can carbon monoxide incidents be terminated?

The correct answer is based on guidelines for safe levels of carbon monoxide exposure. Readings below 8 parts per million (ppm) indicate that the environmental concentration of carbon monoxide has dropped to a level considered safe for human health. At this concentration, the risks associated with carbon monoxide exposure are minimal, allowing responders to safely terminate the incident.

When carbon monoxide levels are higher, such as those below 35 ppm, there might still be potential health risks for vulnerable populations, especially over prolonged exposure. Levels below 1 ppm are extremely low and sometimes outside the sensitivity of detection equipment typically used in these scenarios. Additionally, stability in readings is important for safety assessment, but it alone does not guarantee that the environment is safe, which is why it is key to rely specifically on the concentration levels measured.

In summary, terminating an incident when levels are below 8 ppm ensures that the air quality is at a safe threshold for those potentially exposed.