Poor Air Quality During Sleep – Measurements in the Bedroom

Measurements of Carbon Dioxide (CO₂) concentration at night were conducted in the bedroom of an insulated house. The bedroom had an area of 45 m² and was fitted with new plastic windows. Two adults and a one-year-old child slept in it. The sensor recorded an increase in CO₂ concentration to more than three times the recommended value. “The air measured over 3,000 ppm of carbon dioxide, which is far beyond the threshold for a quality sleeping environment,” says Ing. Miloš Žáček, Executive Director and Managing Director of Protronix.

Graph No. 1: Measured Values with Completely Closed Windows

The following night, measurements were taken with the same number of people but with micro-ventilation, enabled by the less airtight installed windows. The maximum recorded CO₂ values were lower (2600 ppm), and from one o’clock in the morning, the concentration dropped significantly, reaching the recommended level by morning.

Graph No. 2: Measured Values with Micro-Ventilation

The third measurement was conducted with the window tilted open. The level of carbon dioxide concentration exceeded just slightly above 1200 ppm at its highest point. The measured concentration level corresponded to an airflow rate of about 23 m³ of air per hour per person, which meets the generally accepted requirement for fresh air in a room.

Graph No. 3: Measured Values with Tilted Window