Office Air Quality Explained: How To Improve Your Work Environment

Maintaining healthy air quality in your office.

Indoor Air Quality can affect staff productivity by up to 11% – it is one of the most important issues affecting businesses today, and yet – many still ignore it.

With winter drawing in, naturally, we shut the windows to lock out the cold and keep all the doors shut to stop any drafts creeping in. But what does this mean for the quality of the air circulating in the office? In short: this could result in potentially harmful levels of CO2 building up, causing lack of concentration, tiredness, headaches and overall discomfort to staff.

We recently embarked on a mission to improve our office air quality, monitoring it constantly for any changes. We measured: Volatile Organic Compounds (VOC’s), Carbon Dioxide (CO2), Carbon Monoxide (CO), Nitrogen Dioxide (NO2) and Methane (CH4) here’s what we found…

  • Volume of staff quickly impacted CO2 levels – Carbon Dioxide levels in the main office spiked around 11am, after we’d all been here for a few hours. It also dropped on Wednesdays and Friday’s – when we have less people here in the office. When we had a group meeting, it took just ten minutes for levels to rise to problematic levels in the office.
  • VOC’s increased around lunch time – We think this could be due to a lot of sudden movement and activity in the office and possibly some interesting meal choices.
  • Opening exterior windows dropped CO2 levels quickly and effectively, it did however up levels of NO2 in the office (car exhaust).
  • We could reduce our CO2 levels drastically just by opening interior doors and creating air flow within the building (without the need to open exterior windows).
Data from experiment – The data shows the fluctuations day-to-day over a week period. You can see the large spike in CO2 on Monday – caused by a group meeting.

What causes poor indoor air quality?

There are a number of factors that contribute to a drop in IAQ

CO2 levels

Unfortunately, we all produce CO2 simply by respiring. Levels can quickly reach high thresholds in crowded offices. You can measure CO2 using most Air Quality Monitors, levels of CO2 are measured in parts per million (ppm). Anything over 1000ppm can become problematic. Over 1500ppm is where you’ll start to see drowsiness and a lack of concentration. Between 2000-5000ppm can trigger headaches, loss of attention, increased heart rate and nausea. Anything over 5000ppm (the workplace exposure limit) is a severe problem and must be rectified immediately.

Volatile Organic Compounds (VOC’s)

Volatile Organic Compounds are the chemical vapours released from various items. Some have higher (more ‘volatile’) evaporation rates, but most evaporate at room temperate. Many of the things surrounding you in the office will give off VOC’s. The worst offenders include; cleaning products, printers/copiers, electronic devices and even furniture. VOC’s are associated with respiratory issues, allergies and eye/nose/throat irritation. Levels of VOC’s are usually between 2-5 times higher indoors than outdoors, so it’s important to ensure they’re not building up in the office.

Outdoor Air Quality

Most outdoor pollution can be categorised into either PM10, PM2.5 or PM1.0. PM10 are particles smaller than 10 microns, these are usually more natural materials like dust, pollen and mould. PM2.5 are smaller than 2.5 microns, these are usually materials such as vehicle exhaust, smoke and industrial emissions. While PM10 pollution can be irritating and in some cases, dangerous, PM 2.5 is far more destructive, causing millions of deaths worldwide every year. This is why opening a window and letting all of this pollution flood in can actually make your indoor air quality worse, especially if you’re in a particularly built-up, industrial area. Arguably the most dangerous of them all is PM1.0, so small it can travel deep inside the body and cause serious respiratory issues. The rule of thumb is: the smaller the particle the more damage it can do to us.

Biological Contaminants

Bacteria, Pollens and Mould Spores can all wreak havoc in an office, causing allergies and infections. Carried in by staff, these biological contaminants can impact your IAQ drastically if not kept under control.

What can you do to improve your office air quality?


 In order to improve AQ you need to be able to reliably track and monitor it. This is surprisingly easy to do, with a range of affordable, non-intrusive monitors available complete with web-based apps that clearly show you in real-time what’s in the air around you. Although – it’s worth doing your research as unfortunately there’s some unreliable options available on the market.  

Once you’ve been monitoring the air in your office for a few days you’ll start to notice patterns in your AQ. For example, we noticed that at around 11am every morning, CO2 levels started to really surge, simply because we’d been sat there breathing for 3 hours! To overcome this in the short-term, we started opening internal doors as soon as we came to work, meaning there was a constant change in the air circulating in the room.


Avoid products with high VOC’s where possible:

VOC’s are given off by lots of common place items in the office – also known as ‘off-gassing’ – but you can reduce your exposure to them. Brand new items release a lot more vapour than older ones, a new item will be most ‘toxic’ in the first few months. When buying new furniture, for instance, you can avoid materials that will give off high levels of VOC’s. These materials include; composite woods, furniture padding using polyurethane foam and a lot of paints, stains and sealants.

Effective Cleaning:

Keeping particulates such as dust and contaminants at bay is essential for cleaner office air. This can be aided by regular, thorough cleaning. Special attention should be given to those warm, damp corners of rooms or carpets that get a lot of traffic. Make sure you use a Vacuum with a HEPA to trap the particulates you’re collecting – otherwise you’re just throwing them back into the air. It’s important to clean out-of-hours, preferably after staff have gone home (not before they arrive), as cleaning fills the air with the particulates you’re trying to get rid of.


Keeping a relatively cool temperature will help keep biological contaminants at bay and may slow VOC release rate. Humidity also plays a large role in balancing air quality. Maintaining a relative humidity of between 30-60% will help to control mould and dust. It’s especially important to keep HVAC systems such as Air Conditioners and Heaters clean and change the filters. Without this, they can pump an abundance of harmful particulates back into the air.



The only way to truly improve your air quality in the long-term is to install an effective, filtered ventilation system in your office. Making sure you keep it functioning effectively, bringing clean air in and removing the harmful particulates in the room. The temptation is to just throw open a window, and whilst this will help reduce the CO2 levels, the high levels of pollution outside can mean you’re letting in more harmful particulates than you’re letting out – especially if you’re based in a busy city. Indoor ventilation will help, simply opening interior doors will help air flow within the building, lowering CO2 levels.

Air purifiers:

HEPA filter equipped purifiers do a good job of filtering out various contaminants, such as pollen and dust. Some air purifiers also remove VOC’s from the air, making your office space a much more pleasant place to be. However, in order to do this the purifier needs to have a carbon filter. It’s worth doing some extensive research when looking for a purifier as we’ve found a lot of brands are misleading with their packaging. Always make sure the purifier has a thick, true carbon filter (expect around a kilo of carbon.) Check if the filter is re-usable as filters will need to be changed every 3-6 months and can be costly. Finally, make sure to take note of the ‘Air Changes Per Hour’ rate, as these are often misleading and apply when the product is used in a much smaller room than intended.


We tested this old theory by filling the office with a selection of ‘Mother in Laws Tongue’ and ‘Areca Palm’, two of the best plants previously recommended for this purpose. We didn’t find much evidence that the plants had made a difference to CO2 levels. They did improve morale though and made a nice addition to the office. Plants are also natural filters for certain toxins, so they’re still worth having around.


Having good air quality in the office is essential. As concerns grow surrounding AQ around the world, increasing pressure is being placed on authorities to clamp down on companies with poor AQ. Making these changes now will make the transition to a safer, more productive workplace easier, so we can all breathe a little easier.

For more information contact our experts

Phone: 01905 362100