A carbon dioxide level of approximately 40,000 parts per million poses an instant danger to health and life, according to the Minnesota Department of Health. The Minnesota Department of Labor and Industry established workplace guidelines indicating that the average concentration of carbon dioxide should not exceed 10,000 parts per million over an eight-hour period and 30,000 parts per million over a 15-minute period.
Sustained exposure to carbon dioxide levels higher than 5,000 parts per million can result in dizziness, headache and nausea, advises the Minnesota Department of Health. Asphyxiation can occur at higher levels as the carbon dioxide replaces oxygen in the blood.
Carbon dioxide levels determine ventilation needs, explains the Minnesota Department of Health. The level of carbon dioxide indoors varies based on factors such as room or area size, length of time the area houses people, the number of people in the area, the amount of fresh air entering the room, and the outdoor concentration.
Carbon dioxide occurs due to exhalation into the air, decaying vegetation and the burning of fossil fuels, explains the Wisconsin Department of Health Services. Carbon dioxide can exist as a solid or a liquid. In its solid form, carbon dioxide finds use as dry ice and in laboratories and fire extinguishers.