Test: Sweden released the 2013 Chinese version of the white paper “Indoor Air Quality and Human Health.” It states that particulate matter in indoor air poses an even greater threat to health. Previously, studies by the U.S. Environmental Protection Agency (EPA) also indicated that indoor air pollution levels are 2 to 5 times higher than outdoors, and in special cases, can reach 100 times.

The white paper points out that when PM2.5 levels exceed standards, staying at home is not necessarily a wise choice. There are more than 400 chemical substances and 900 different organic compounds indoors. Pollution comes from all aspects of life, yet the threat of indoor air to human health is the most easily overlooked.

The World Health Organization (WHO) once published an article stating that 4% of global diseases, including pneumonia, chronic respiratory diseases, and lung cancer, are related to indoor air quality. The white paper notes that because children, pregnant women, the elderly, and the chronically ill spend more time indoors, they are more vulnerable to indoor environmental pollution; among them, children and infants inhale nearly 50% more air per kilogram of body weight than adults.

The white paper indicates that two effective methods for addressing indoor air pollution are increasing ventilation and using air purifiers. If an air purifier is used, it should comply with the international standard for measuring the overall performance of air purifiers established by the Association of Home Appliance Manufacturers (AHAM), known as the Clean Air Delivery Rate (CADR). According to reports, the CADR standard is specifically used to measure the overall efficiency of air purifier products in removing pollutants, mainly testing three of the most common and representatively sized air pollutants: large-particle pollen, medium-particle dust, and small-particle secondhand smoke. A higher CADR value represents a higher efficiency of the air purifier in removing indoor air pollutants.

The white paper believes that in addition to complying with CADR standards, air purifiers should ensure they do not produce ozone during the purification process, which causes secondary harm to the human body. The best solution is to adopt dual technology—electronic absorption and mechanical filtration—in addition, low noise and energy-saving technologies are also particularly important.