November 28, 2023 What’s the Difference Between IAQ & IEQ?

There are different ways of measuring air quality so we need to not only be aware of our IAQ but our IEQ as well.

The quality of the air that we breathe is incredibly important no matter where we are. Most of us understand that when outdoors we are subject to all manner of pollutants, but this can mean that we give little thought to the quality of the air when we are indoors.

As most of us spend more time indoors rather than out, the quality of the air in our homes, offices and schools can be incredibly important and it is something that we should pay a lot more attention to.

There are different ways of measuring this and different factors to consider, and so we need to not only be aware of our IAQ but our IEQ as well in order to have an all-round healthy and harmonious environment.

In this article, Ian Gregory, Managing Director of IAQ Services takes a look at what IAQ and IEQ means and how they differ from one another and where the similarities lie.

What is IAQ?

IAQ stands for Indoor Air Quality, which is a measure of how healthy the air is inside a building. If the IAQ is poor, then there is a risk of allergies, viruses, illnesses and respiratory issues. The things that can contaminate our IAQ can come from many different places such as our pets, the things that we cook, general dirt, the things that we bring in on our shoes, the cleaning products that we use, mould that can develop, our fireplaces and even paints.

IAQ can also be affected by outdoor pollutants that come in from outside through open doors and windows. The COVID-19 pandemic has also made us all more aware of what is in the air around us and the extent to which we contribute to this. We are capable of projecting viruses and bacteria into the atmosphere every time that we breathe, cough or sneeze, and when a number of people are crammed together at once, the air quality can decrease dramatically.

IAQ is measures using parameters that relate to temperature, humidity, carbon dioxide, volatile organic compounds (VOCs), particulate matter and chemical pollutants. There are meters which can be installed indoors to measure the IAQ in any given space and warn you if it is heading into dangerous territory.

The World Health Organisation (WHO) has set out what acceptable air quality limits should be, but admits that over 80% of people who live in metropolitan areas are exposed to air quality levels that exceed this. Luckily, there are things that we can do to improve our IAQ, including using proper ventilation systems, air filters and air purifiers to remove some of the harmful particles that are in the air.

What is IEQ?

Indoor Environmental Quality (IEQ) takes into account the more general conditions inside a building that might affect its occupants. There are four well known elements of IEQ, which are thermal conditions, lighting, acoustics and air quality. These work together to create an optimal environment for those within it.

Thermal comfort refers to the temperature inside the building and ensuring that this comfortable and well regulated. There are lighting sequences which can be tied to our circadian rhythms to affect how we feel, and acoustics show how the sound around us also influences our feelings. The air quality aspect then considers our health as well as feelings.

There have been several studies that have shown a link between poor IEQ and increased numbers of sick days by employees who work in the building.  Good air quality solves one problem, but it cannot solve all of them, and so there can still be plenty of factors affecting wellbeing.

What are the similarities between IAQ and IEQ?

The biggest similarity that exists between IAQ and IEQ is that both consider the quality of what we breathe, but the emphasis of this is different with each one. What does become apparent is that both can be affected by systems that can be built into properties, such as air conditioning systems, air filters, dehumidifiers and air purifiers.

It is also the case that both are influenced by the people within the building and what they do there. The things that they bring into the building and the activities that they partake in while they are there can all impact on both IAQ and IEQ.

What are the differences between IAQ and IEQ?

One of the clearest differences between the two is that IEQ is a much broader term which takes into account a range of factors that impact on the environment as a whole. Whilst it considers air quality, this is just one of the elements within it, as IEQ looks at what affects our mental wellbeing as well as the physical.

IAQ tends to focus on the very specific elements of the quality of the air within a building. It plays a part in IEQ, but it is not all that there is to it. Good IAQ can lead to good IEQ but it cannot do this on its own, and so other factors also need to be taken into consideration.

Another big difference is the regulation that both are subject to. There are laws and building codes that set out what the IAQ should be and what is considered to be dangerous, but as IEQ can be harder to measure, there are no hard and fast rules around this.

Many IAQ rules have requirements for HVAC and ventilation systems, particularly in public places such as schools but there is currently no national standard for IEQ.

Instead, the owners of the building and the operators of it are left to decide what they feel is a good IEQ, and as this can be somewhat subjective, the results can vary.

Whilst IAQ looks at the impact of the air on our health, IEQ focuses on factors that can affect much, much more, including our productivity, our comfort and our overall wellbeing. It is the difference between thinking about the air that we breathe and what we breathe, see, feel and hear all at once.

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