Air Quality Index
What is CO2?
Carbon Dioxide or CO2 is a greenhouse gas that is natural and harmless in small quantities but as levels rise it can be dangerous to your health. Most commonly produced by the air we exhale, CO2 levels concentrate indoors with less ventilation. It is one of the most important gases on the earth because plants use it to produce carbohydrates in a process called photosynthesis. 350-1,000 ppm concentrations are typical of occupied indoor spaces with good air exchange.
Formaldehyde (HCHO) is the most important carcinogen in outdoor air. The World Health Organisation guideline for indoor air formaldehyde (HCHO) concentration is 0.10 mg/m3. The California Air Resources Board recommends an “action level” of 0.10 mg/m3 and a “target level” of 0.05 mg/m3 or lower for homes. Average concentrations in older houses with UFFI are generally well below 0.10 mg/m3.
What are TVOCs?
TVOCs stands for Total Volatile Organic Compounds, which are the total amount of any emitted gases with short or long-term health effects. TVOCs can cause serious health effects in both the short and long term. Health effects vary from minor eye, nose and throat irritations all the way to liver and kidney damage or cancer, depending on the level of exposure. Action level of 0.50 mg/m3.
Nitrogen Dioxide (NO2)
The effort to reduce NO2 also needs to be targeted on the sources that make the biggest contribution to the problem: road vehicles contribute about 80% of NO2 pollution at the roadside and growth in the number of diesel cars has exacerbated this problem. The law states that hourly levels of NO2 must not breach 200 micrograms per cubic metre (µg/m3) more than 18 times in a whole year. This limit is regularly broken in London.
Guidline for indoor air formaldehyde (HCHO) concentration is 0.08 ppm (0.1mg/m3). The California Air Resources Board recommends an “action level” of 0.1 ppm and a “target level” of 0.05 ppm or lower for homes. ... Average concentrations in older houses with UFFI are generally well below 0.1 ppm. The World Health Organization