CO2 does not cause asthma.
CO2 levels are a reflection of ventilation. Obtaining CO2 levels is a way to evaluate if there is enough outdoor air exchange. CO2 is exhaled from our lungs with each breath; we are the source of CO2. Outside air introduced into a space helps keep the levels down. Controlling asthma triggers like fragrance and dust in a school is equally important to overall school indoor air quality.
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