We often think of our homes and offices as safe havens, yet indoor air can be laden with pollutants that harm our health and well-being. From gases released by furniture and building materials to mold spores, fungi, and viruses, the air indoors can be a cocktail of harmful substances. These issues have gained attention since the 1970s under the term “sick building syndrome.” Alongside poor lighting, noise pollution, and psychological stress, contaminated air is a major contributor to this condition.
The Role of VOCs in Air Pollution
Volatile organic compounds (VOCs) are a primary source of indoor air pollution, posing significant health risks. VOCs such as benzene, formaldehyde, and naphthalene are emitted by everyday items like furniture and construction materials. These compounds not only harm health directly but also react with ground-level ozone to create secondary pollutants.
Environmental guidelines now regulate VOC concentrations in indoor spaces, making continuous and reliable monitoring essential. Non-dispersive infrared spectroscopy (NDIR) is particularly effective for VOC detection due to the strong absorption of VOCs in the infrared spectrum.
CO₂: A Reliable Indicator for Air Quality
Carbon dioxide (CO₂) is not just a natural component of our atmosphere; it’s also a key indicator of indoor air quality. While outdoor CO₂ levels hover around 400 ppm, concentrations indoors can rise rapidly, particularly in crowded spaces. Each human breath releases approximately 40,000 ppm of CO₂, which accumulates alongside other pollutants.
Air quality is considered hygienically safe up to 1000 ppm of CO₂. Beyond this level, air exchange or purification becomes necessary. NDIR technology is ideal for monitoring CO₂ levels, as CO₂ strongly absorbs infrared light at a wavelength of 4.26 µm.