CO2 monitoring: a benchmark for indoor air quality? Skip to content

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CO2 monitoring: a benchmark for indoor air quality?

As businesses seek to make their workplaces healthier, real-time indoor air quality monitoring has shifted to the top of the priority list for many smart building software providers and system integrators.

Buildings play a crucial role in supporting our health and well-being.

That’s why monitoring indoor air quality is likely to become fundamental strategy for many businesses.

Well-insulated buildings keep us warm. But rising carbon dioxide (CO2) levels can lead to stale, stuffy air and lead to tiredness and headaches. This can affect workers’ comfort and well-being, as well as their productivity. Employers have a responsibility to provide a healthy working environment, so it’s perhaps not surprising that more businesses are using environmental monitoring to assess and maintain temperature and air quality.

But there’s another good reason to monitor CO2 levels – the increasing evidence that carbon dioxide levels in buildings have a strong correlation with airborne spread of infection. Essentially, this means that CO2 monitors could act as the “canary in the coalmine” to mitigate the coronavirus threat.


Keeping up with the latest regulations

But businesses are worried. A recent poll shows that only 1 in 4 businesses (27%) know how to return their staff to the office safely after Lockdown. And businesses are right to be concerned: Aside from the obvious health benefits, there are regulations employers must comply with, too.

From the Health and Safety at Work Act 1974 through to the Building Regulations 2010 for manufacturers, and the new and revised workplace exposure limits (WELs) which came into force from January 2020 – there are a raft of regulations to consider.

In addition, across the continent, European standards include guidelines developed by the WHO for indoor air quality. These give pollutant concentrate thresholds, with companies expected to develop and implement improvement plans if these levels are excelled.

And globally, WELL standards are the leading tool for advancing health and well-being in buildings globally.

In order to ensure a business is complying with these regulations, previously, indoor air quality tests were done in-person, maybe once or twice a year, with measuring equipment brought into the building. However, the desire to make buildings healthier could trigger a sea change for real-time air monitoring.


How CO2 levels can determine air quality

 The established benchmark test for indoor air quality is to assess CO2 levels, as they are a good general indicator of air freshness.

Carbon dioxide is released into the air when we exhale. So CO2 concentration is determined by how many people are in a building as well as how much fresh air is being brought in. In general, the higher the concentration of CO2 in the building in comparison with outdoors, the lower the amount of fresh air exchange.

Without adequate indoor ventilation, CO2 levels naturally build up over time.

Looking at the figures: the background level of CO2 outdoors is generally believed to be in the range of 350-500 parts per million (ppm).

In a well-managed indoor space they are generally 350- 1,000ppm. Go above 1,000ppm and this is when people will start to notice the stuffy atmosphere or poor air quality.


How can sensors improve indoor air quality?

Asides from keeping spaces well ventilated to prevent the build-up of pollutants, what might bring people some peace of mind, is installing IoT sensors in office buildings and other workspaces.

Just opening a window is scratching the surface. The thickness of outer shells of a building combined with their capacity to trap pollutants internally mean that this type of occasional ventilation won’t give you the desired CO2 levels.

Good indoor air quality can only be guaranteed by using a ventilation system which operates based on the data from CO2 sensor. Otherwise, you’re simply taking a wild guess as to when you need to increase ventilation.

An image of Pressac wireless CO2, temperature and humidity sensor installed on the wall of an office

Air quality sensors can be used to monitor changes to air quality and detect the presence of various gases. The data from these sensors can be viewed in real-time, giving an instant view of ambient conditions in each room.

This live data can then be fed into your software solution for automated, demand-driven HVAC control.

Pressac’s wireless CO2 sensor can also monitor temperature and humidity to give a rounded view of air quality. Our small, solar-powered sensor uses ultra-low power wireless technology, making it easy to install and very low maintenance.

It’s a common misperception that improving ventilation in a massive office building is hard and expensive. It doesn’t have to be expensive. Smart sensors are a very simple and cost-effective solution to integrate into your software or app.


Monitoring air quality on a real-time basis is the best way to get accurate data. Smart sensors feeding back data on CO2 levels, temperature, humidity and occupancy give you granular detail on your activity. This combined approach can help you operate more efficiently, more responsibly… and more productively.

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