What is the IDLH level for Carbon Dioxide?

The correct identification of 40,000 parts per million (ppm) as the IDLH (Immediately Dangerous to Life or Health) level for carbon dioxide is based on safety guidelines established by occupational health standards. The IDLH level is defined as the concentration at which an individual may be exposed for a brief period without experiencing irreversible health effects or impairment.

For carbon dioxide, which is a colorless, odorless gas that can displace oxygen in the air, the high IDLH threshold reflects the potential for rapid asphyxiation in environments with limited oxygen. Prolonged exposure even at lower concentrations can lead to symptoms such as headache, dizziness, or loss of coordination, but the threshold of 40,000 ppm is defined to provide a clear and actionable safety limit, ensuring that workers are warned of hazardous environments where the gas could affect health.

The other options reflect lower concentrations, which do not align with the established IDLH level for carbon dioxide and could mislead individuals about the safety and health risks when working in environments where carbon dioxide is present. Hence, recognizing the correct IDLH level is crucial for ensuring worker safety and adopting appropriate precautionary measures.