How to Manage Indoor Air Quality: 3 Key Steps

Air that is of high quality is necessary for a healthy home. Contaminants that damage or irritate us, have an unpleasant scent, or interfere with our ability to see appropriately (smoke) can impair the air quality within buildings.

These toxins may be released inside the home (from furniture, household products, stoves, pets, and people) or originate outside. Which impact humans differently depending on how potent or harmful they are. Making managing indoor air quality a necessity for a healthy home.

This article will cover how to manage indoor air quality by using three key methods:

  • Dilution
  • Containment
  • Controlling sources

Healthy Indoor Air is a Human Right

The World Health Organization (WHO) declared clean indoor air a human right in 2000¹. (WHO Regional Office for Europe 2000).

There are, however, few legal regulations that outline safe levels of indoor pollutants in residential buildings, notwithstanding this pronouncement and the significance of air quality in our homes.

Most laws either pertain to businesses or the open air. However, regardless of where we are exposed, the effects of air pollution concentrations on our wellness will be the same.

There may not be any legally enforceable thresholds for home environments due to the wide range of potential contaminants and the often intrusive analytical equipment used to measure them, which is typically not a concern for outdoor or occupational air monitoring.

So what choices do we have for controlling the air without turning our house into a laboratory?

The best approach to improving indoor air quality in homes is to avoid using pollutant-emitting products and materials and to filter any dangerous components out of outdoor air before it enters the building. 

This approach is incredibly challenging, though, as most building material producers are not obligated to list ingredients, and we sometimes have no idea what other household products are made of. 

For example, do you know what contaminants your bathroom cleaning spray contains? Additionally, smells and particles are a byproduct of regular house use, and breathing emits carbon dioxide (CO2).

Therefore, it is impossible to fully control the source of contaminants while people are still living in their homes. In addition, the pressure created by natural forces is insufficient for outdoor air to flow through a filter consistently. 

People often think their house is “breathing,” but that is only when enough wind pressure is present. On a calm day, there could be no air movement in a home without mechanical ventilation.

Therefore, filtering contaminants from outdoor air before it enters the home is only practically possible when mechanical forces are utilized for ventilation.

3 Solutions to Managing Indoor Air Quality

  1. Dilution: Ventilation maintains pollutant levels within a specified range
  2. Containment: Capture and remove pollutants from their source (such as a range hood for an oven)
  3. Controlling Sources: Not bringing in items that emit pollutants and not allowing outdoor contaminants inside the home

Containment of pollutants and excessive humidity is the next step in improving indoor air quality in the home, for instance, employing range hoods or extractor fans in the kitchen and bathroom to remove pollutants and humidity at their source before spreading.

Coatings can also trap pollutants and stop them from dispersing into the air when used on problematic materials. 

Fresh air ventilation can be the most reliable process because it is entirely within our control.

It takes about 30m³ of fresh air per person every hour to keep pollutant concentrations under control.

Additionally, it is essential to ensure that this fresh air is effectively circulated throughout the interior space. For instance, having a bathroom with good ventilation does not guarantee that the other rooms in the house would have high indoor air quality. 

Therefore, an air management system must constantly provide each person with enough fresh air every hour.

Even more fresh air is required for areas with more potent polluting sources. For instance, smoking requires a significant increase in fresh air flow rate to dilute hazardous chemicals adequately.

Use a Home Indoor Air Quality Monitor For CO2

To determine whether the ventilation system produces the desired results, monitoring CO² concentrations inside the home is advised.

In addition, CO² levels are a good indicator of other gaseous indoor air pollution concentrations since they are relatively unobtrusive and affordable to monitor. 

Due to the frequent inclusion of a CO² threshold in mechanical ventilation standards, 1000 ppm (ppm) is frequently used as a static value. However, acute toxicity is only likely at concentrations 20 times higher than this number, CO² concentrations above 1000 ppm have been seen to cause sleepiness, lack of focus, headaches, and an accelerated heart rate². 

However, it pays to ensure that the system designer specified volume flow reaches the spaces as planned and fulfills the requirements there, even with a good ventilation system. 

The most dependable technique to stop air pollutants from accumulating and negatively impacting your health is diluting with fresh air.

In a house’s architecture, the distribution of fresh air shouldn’t be an afterthought; it requires a clear concept and a quality assurance procedure. However, it should be verified.

The outside air may be contaminated, and fibers and other materials may impede any air that enters the building through the building envelope.

Some standards, instead of a fixed value, permit a maximum variation in outdoor concentration levels. For example, using this method, the threshold is lower for a home in a forest with lower CO² and outdoor concentrations than for a house close to a roadway.

Intensities above 1500 ppm are considered alarming, regardless of where the structure is located.

Overnight CO2 levels in bedrooms will likely rise if windows and doors are closed.

In such a bedroom, the options on a winter night are to keep the windows closed, which creates warm, stuffy conditions, or to open the window, which leads to cold, fresh conditions. The problem with this is it could cause a headache or a stiff neck when you wake up. 

Only when heat from the stale air leaving the room is transferred to the fresh air that is coming in can we sleep wonderfully healthy, warm, and comfortable.

This is made possible by air ventilation systems called an ERV (Energy-recovery ventilator) or HRV (Heat-recovery ventilator). Which of these you choose will depend on your climate and the HVAC system.

Both systems will help bring consistent fresh, filtered air into your home. And save more energy than an open window (or leaky home, read our article on home air barriers).

References + Resources

1.) The Right to Healthy Indoor Air: WHO; PDF Link

2.) CO2 levels PPM and health; ScienceDirect.com – Link