What Level of CO2 is Harmful to Humans: Understanding the Risks

Understanding Carbon Dioxide and Its Effects

Carbon dioxide (CO2) is an odorless gas composed of a carbon atom bonded to two oxygen atoms. It plays a critical role in Earth’s processes and is vital for sustaining life. While carbon dioxide is crucial for natural processes, elevated levels can lead to significant health and environmental risks.

CO2 in the Atmosphere: Carbon dioxide exists in Earth’s atmosphere as a trace gas, comprising approximately 0.04% (or 400 parts per million [ppm]) of the air. This gas helps regulate the Earth’s temperature through the greenhouse effect, which is necessary for life.

However, when human activities such as fossil fuel burning increase CO2 concentrations, it contributes to climate change and environmental degradation.

Greenhouse Gas: As a greenhouse gas, carbon dioxide absorbs heat and keeps Earth warm. However, high levels of Carbon dioxide in the atmosphere trap excess heat, leading to rising global temperatures and disruptions in weather patterns. Reducing CO2 emissions is essential for mitigating climate change.

Role in Photosynthesis: Carbon dioxide is a crucial part of photosynthesis, where plants convert carbon dioxide and sunlight into oxygen and glucose. This process supports life by generating oxygen, vital for humans and animals.

Human Impact and Emissions: Since the Industrial Revolution, human activities have dramatically increased CO2 levels. Excess carbon dioxide leads to ocean acidification, habitat loss, and global warming. Adopting clean energy sources and improving air quality through better practices can help maintain a healthy environment.

Health and Indoor CO2

While CO2 levels in outdoor air are generally safe, high concentrations of carbon dioxide indoors can pose significant risks to human health. In poorly ventilated indoor environments, such as homes or offices, elevated CO2 concentrations can lead to symptoms like headaches, dizziness, fatigue, and even impaired cognitive function. When indoor CO2 levels surpass 1000 parts per million (ppm), these health effects become more pronounced. If CO2 concentrations exceed 5000 ppm, they can be considered dangerous levels of exposure, affecting not only comfort but also productivity. To mitigate these risks and improve indoor air quality (IAQ), installing CO2 monitors is crucial. These devices help track CO2 levels and ensure proper ventilation, preventing exposure to harmful concentrations of carbon dioxide.

See also our article on how candles affect air quality - Does burning candles affect the air quality?

Typical CO2 Levels and Indoor Air Quality

Outdoor air typically contains around 400 ppm of CO2, which is safe. However, indoor air concentrations can rise above 1000 ppm, especially in occupied spaces with poor air exchange. High levels of CO2 indoors signal a need for better ventilation to avoid poor air quality.

CO2 as an Indicator of Indoor Air Quality: Monitoring CO2 levels can help evaluate indoor air quality (IAQ). Low levels of CO2 indicate good ventilation, while higher concentrations can lead to stuffy air and discomfort.

Here you can see more information about the Carbon Dioxide Levels.

~400 ppm	Background (normal) outdoor air levels
400 - 1,000 ppm	Typical levels found in occupied spaces with good air exchange
1,000 – 2,000 ppm	Levels associated with complaints of drowsiness and poor air
2,000 – 5,000 ppm	Levels associated with headaches, sleepiness, and stagnant, stale, stuffy air Poor concentration, loss of attention, increased heart rate and slight nausea may also be present
> 5,000 ppm	Dangerous air for human health and long-term survival

 

Health Risks of High CO2 Exposure

Prolonged exposure to elevated CO2 levels can have significant health effects. Symptoms of poor concentration, headaches, and respiratory distress can occur in environments where CO2 levels exceed safe thresholds.

CO2 poisoning is rare but can occur in situations where CO2 concentrations are excessively high, such as in confined spaces where oxygen is displaced by CO2. In such cases, it can lead to asphyxiation and even death.

Symptoms and Warning Signs of High CO2 Exposure

Even low concentrations of CO2 can cause discomfort, making individuals feel drowsy and unfocused. As CO2 concentrations rise, symptoms like headaches, dizziness, and nausea can become more common.

If exposure continues, prolonged exposure can lead to more severe health effects, including increased heart rate and difficulty breathing. Monitoring CO2 levels and improving ventilation can prevent these risks.

Read about the Hidden Dangers of Poor Air Quality and How it Affects Your Health: Discover the symptoms and understand how poor air can impact your well-being.

Safety Precautions and Ventilation Strategies

Using air quality monitors is essential for tracking CO2 levels in enclosed spaces. Maintaining good air exchange through proper ventilation can reduce exposure to high levels of CO2 and prevent health problems.

Exposure Limits and EPA Standards

The U.S.Environmental Protection Agency (EPA) recommends keeping indoor CO2 levels below 1000 ppm. In work environments, the threshold is 5000 ppm for an eight-hour shift and 30,000 ppm for a 15-minute period.

Preventing High CO2 Exposure in Indoor Spaces

To avoid harmful CO2 concentrations, it’s important to regularly ventilate spaces and monitor indoor air quality. Avoid storing large amounts of solid carbon dioxide (dry ice) in closed environments, as it can sublimate into CO2 gas, increasing CO2 levels rapidly.

Additionally, fire extinguishers containing CO2 should be used cautiously in confined spaces to prevent exposure to dangerous levels of carbon dioxide.

Conclusion

Understanding what level of CO2 is harmful is critical for promoting healthy indoor environments. By monitoring indoor air quality, improving ventilation, and taking safety precautions, we can reduce the risk of high CO2 exposure and maintain a healthier environment. Continued research and awareness are essential to ensure safe CO2 levels and protect human health.

To ensure the safety of yourself and your loved ones and clearly understand the CO2 levels in your home or workplace, check out Airvalent CO2 monitors. They are the smallest in the world and feature an attractive design with a screen.