Air filtration

Indoor Air Quality (IAQ)

Continuous air replacement leads to energy waste, but air scrubbing can reduce the need for outside air.
enVerid indoor air treatment

The Importance of Good Indoor Air Quality

Indoor air quality (IAQ) directly affects the health and productivity of building occupants, making it one the most critical aspects of indoor environments. 

While some contaminants appear as “particles,” such as dust, that can be captured by conventional filters, others appear as free-floating molecules, far too small to be filtered. For this reason, air replacement has been the only way to offset the buildup of these “molecular” contaminants. This is particularly true of CO2, by far the most abundant indoor-generated molecular contaminant, though equally relevant are volatile organic compounds (VOCs). Read more about research results showing the detrimental effects of increased CO2 levels on our brains. Indoor air treatment is one of four integrated capabilities in enVerid’s HLR® (HVAC Load Reduction®) module. enVerid’s game-changing approach is based on molecular cleaning of indoor air. In its “adsorption” mode of operation, the HLR system utilizes a combination of novel, efficient adsorbents to capture molecular contaminants and clean the inside air. Simultaneously reducing the amount of outside air being brought into buildings reduces the load on the HVAC system to heat or cool the air. The result: significant energy savings.  

Cleaning Indoor Air

With standard HVAC systems, all of the air in a building is replaced every 1-2 hours. In some buildings, that means 20 times the entire volume of the building’s air capacity passes through the building every day. That air doesn’t enter the building at room temperature, so vast amounts of energy is wasted heating or cooling the air to a comfortable level. To reduce this waste, buildings can use HVAC Load Reduction® (HLR) modules to scrub the indoor air to maintain indoor air quality. When doing this, the building can use less outside air changes – creating a huge energy saving.

The HLR system is the only commercially available solution that effectively captures CO2, VOCs and formaldehyde from indoor air in buildings. During the adsorption phase of the HLR’s operating cycle, a small portion of indoor air flows through the sorbents and contaminants are captured, allowing clean air to flow back into the building. CO2 levels are maintained near or below their target parts-per-million (ppm) levels, which can be set by users, even with high occupancy densities. VOCs and formaldehyde levels are also maintained at or below target levels. 

Typically, 60-80% of outside air brought in by traditional air replacement systems can be eliminated by HLR technology, saving heating or cooling energy. Enough air still needs to be brought into the building to maintain positive pressure and make up for mandated building exhaust from bathrooms, but far fewer outside air changes are required with HLR modules.

Keeping Pollution Out of Indoor Air

In environments where the outside air is polluted, whether due to temporary spikes or permanently, the substantial reduction in outside air also reduces the outside contamination loads on the building and the HVAC filtration systems. This enables further cost savings by reducing the frequency of filter replacement.

Furthermore, studies show that bringing outdoor air pollution into a building can be hazardous for both health and productivity. One study from Tufts University found that people living near the polluted air coming off a highway had a higher risk of cardiovascular disease. A study by the National Bureau of Economic Research found that urban pollutants from outside air lowered the productivity of workers.

Productivity Gains

HLR Technology improves indoor air quality in two ways. It cleans indoor air, removing contaminants at the molecular level. It also reduces the need for bringing outdoor air into the building. While outdoor air may be called “fresh air,” it’s hardly fresh. Outdoor air is full of pollutants and reducing ventilation keeps those pollutants out of the building. Indoor air quality is important for more than health and comfort. Studies show that improved indoor air quality increases employee productivity. The National Bureau of Economic Research wrote: 

“We find that higher levels of air pollution, commonly found in major cities, decrease worker productivity.” 

A Harvard study showed that improved air quality led to a $6,500 per employee productivity increase. Based on financial numbers from the Harvard study, a 1% improvement in productivity in a typical office will pay for HLR modules in just 3 weeks. 

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