CO2

What is Carbon Dioxide (CO2)?

Carbon dioxide (CO2) is a natural gas that we exhale when we breathe. It's also produced by combustion processes, such as burning fossil fuels. In indoor environments, elevated CO2 levels are a good indicator of poor ventilation, meaning that there isn't enough fresh air circulating to replace the stale air. While it's not a direct toxin like carbon monoxide (CO), high CO2 levels can still have significant health effects. The concentration of CO2 in the air is measured in parts per million (ppm).

Health Effects at Different PPM Levels

250–400 ppm: Normal Outdoor Air

This range represents the typical concentration of CO2 in clean, outdoor air. It is the baseline for what we consider normal and healthy.

400–1,000 ppm: Well-Ventilated Indoor Spaces

This is the target range for most well-ventilated indoor environments like homes, schools, and offices. Within this range, occupants are unlikely to experience any negative health effects related to CO2.

1,000–2,000 ppm: Initial Symptoms

When CO2 levels rise to this range, it indicates that a space is becoming crowded or that ventilation is inadequate. At these levels, occupants may start to experience some noticeable symptoms, including:

Drowsiness and fatigue
Feelings of stuffiness or stale air
Difficulty concentrating
Reduced cognitive performance, affecting decision-making and problem-solving skills.

2,000–5,000 ppm: Significant Symptoms and Potential Health Concerns

At these higher concentrations, the symptoms become more pronounced and can affect a larger portion of the occupants. The lack of oxygen in the air begins to be noticeable, and the body's respiratory system works harder. Symptoms can include:

Headaches
Nausea
Increased heart rate
Slight shortness of breath

Prolonged exposure to these levels can also lead to increased absenteeism in schools and workplaces due to feeling unwell.

>5,000 ppm: Hazardous and Unsafe

This level is considered hazardous. It is well above the recommended exposure limits set by organizations like OSHA (Occupational Safety and Health Administration). At these concentrations, occupants can experience:

Severe headaches
Rapid breathing
Confusion and disorientation
Elevated blood pressure

Levels above 40,000 ppm can be life-threatening and may lead to seizures, coma, or even death. Fortunately, it is extremely rare for indoor environments to reach such high concentrations unless there is a specific, unventilated source of CO2, such as a leak. The health risks at these levels are directly related to the displacement of oxygen in the air, leading to a state of oxygen deprivation, or asphyxiation.

Page updated

Google Sites

Report abuse