Skip to main content
Air Quality

Your staff don’t want to come back to the office? Here’s what you need to do

By November 12, 2021September 12th, 2022No Comments

It’s been over 18 months since we were told to close our offices and work from home. For some companies this has been a fairly easy and painless switch, for others, however, having their entire staff continue to work from home has proven to be unsustainable.

And those companies face a crucial challenge:

Looking at Government guidelines? That won’t work — the guidelines, once so clear, have become ambiguous, pushing decisions back on employers with vague suggestions such as “employers should provide up to date information and guidance to workers” while not giving that detailed guidance. This confusion has led many to revert to old, outdated advice, with some big-name businesses allocating budgets to cleaning instead of assessing and improving ventilation (the most effective means of reducing Covid transmissions as recommended by both the scientific community and the most recent government recommendations). Orla Hegarty a leading academic from UCD’s school of architecture, planning and environmental policy recently stated that

“public health advice has failed to get across the importance of good ventilation in preventing the spread of the disease”

Employers also need to consider that the general situation has changed from that original advice all those months ago. For one, much of the working population has been vaccinated, but on the other hand, the Delta variant is more contagious than the first versions of the Coronavirus that we had to contend with. And yes, reports have shown that people’s behaviour has changed — increased vaccination rates among the population has increased our willingness to socialise, but many people are still wary and unwilling to take what they see as unnecessary risks.

Then of course there is the changed attitude among the working population.

You’ve likely seen mention of ‘The Great Resignation’ or ‘The Great Attrition’ or one of the other half dozen names or so being used, but they are all telling us one thing; more and more people are leaving their jobs, both white-collar and blue-collar.

In a recent McKinsey report

“53% of the employers said that they are experiencing greater voluntary turnover than they had in previous years, and 64% expect the problem to continue — or worsen — over the next six months.”

As an owner or manager, you need to show your staff that you care about their health and wellbeing. So what if your office offers free beer on Fridays and an air hockey table? That’s not the draw that it was back in 2019. Employees want to see that they’re working in a healthy and safe place.


Over 18 months of intensive study by top experts around the world has let scientists develop a deeper understanding of the virus and its transmission. It has been repeatedly and conclusively proven (for the current Covid variants), that Covid transmission is primarily airborne. Dr Fauci unequivocally stated earlier last month that ventilation is key to reducing the Covid transmission indoors while in the Nagano Prefecture in Japan, CO2 monitors are now being supplied for free to restaurants.

Wearing masks and keeping your distance remain key components to reducing Covid risk, but instead of cleaning surfaces businesses need to concentrate their time and resources on the most effective means of managing Covid risk, and that’s having good ventilation.


Aerosol Transmission
  1. Mask wearing and social distancing:


These remain the best means of reducing Covid transmission. Employers can ‘close’ desks, seating employees a safer distance apart and lay guiding markings on the floor to help people maintain a safe distance as they navigate around the office

2) Indoor Air Quality — CO2 and Ventilation Monitoring:


Proper ventilation is critical to reducing Covid risk indoors. In fact, even if people are sitting a distance apart, recirculated air or an infected person sitting upwind has resulted in cases of Covid transmission.

“For some respiratory infections such as COVID- 19, a low building ventilation rate worsens both long- and short- range airborne transmission”

The best way to assess and monitor ventilation levels is to use CO2 levels as a proxy. If there are high levels of CO2 it means that the ventilation levels are poor and action needs to be taken, whether that is reducing employee numbers in that problem hotspot or keeping nearby windows open. Prof John Wenger published a very short, simple guide that employers can take to improve ventilation.

Measuring CO2

CO2 levels are measured in ppm (parts per million), with approximately 400ppm being the typical atmospheric level of CO2. Recommendations on acceptable levels by various governments and health bodies vary, but it is generally agreed that CO2 levels should not exceed 800ppm — 1000ppm.

What to look for in a CO2 monitor

At the very minimum, you’ll want an indoor air quality solution that is IoT connected, uses a nondispersive infrared sensor (NDIR), is easy to install and displays the data in real-time.

Those are basic requirements. Optimally your solution would not only show you live data but also predict if and when an area is likely to exceed the maximum safe CO2 level before it becomes a problem. This allows you to identify risky hotspots and take preventative actions that keep your employees safe and healthy.

General Air Quality

The temperature and humidity in a room also play a part in Covid transmission.

These are inter-related factors, increasing the temperature in a room typically reduces the humidity. When the humidity in a room is below 20% large virus droplets evaporate to become smaller droplets that float in the air longer. Additionally, studies on Covid transmission have shown that the virus cannot reproduce very well with high levels of humidity.

So what should the humidity levels be?

Guidelines say that to reduce Covid risk, humidity should stay between 40%-60%

3) Upgrading Ventilation


CO2 monitoring can identify a poor ventilation hotspot whose use is essential, think a lab or kitchen. If you’ve minimised the occupancy in the space and CO2 levels are still exceeding healthy levels it’s time to start looking at an engineered solution. You have several options; upgrade the air handling unit (AHU) or A/C, repair and maintain the air handling unit (AHU) ie replace filters, or install a local HEPA filter or air purifier. Finally, the most effective, though typically by far the most expensive option is to make structural changes to the space.

Droplet Transmission



Setting up perspex screens, reduces the risk of transmission via droplets However, it is important to note that the chances of droplet transmission are not especially significant. Another aspect to note is thata study has shown that when screens are used without the ventilation in a room being considered, certain layouts actually resulted in an increased risk of Covid transmission.

Contaminated Surfaces

Cleaning surfaces


Other than clean surfaces being more hygienic in general, studies have shown that contamination via infected surfaces only has a small part to play in Covid transmission; approximately 1 in 10,000 cases are transmitted this way. There is a common public misconception about the dangers of contaminated surfaces. Surveys have shown that people find it reassuring to see surfaces cleaned regularly, although this number is decreasing as the dangers of aerosol transmission become more widely known. The combination of high labour requirements and low effectiveness make this a very costly approach. Instead of investing resources in this method, employers should instead focus on more effective methods and basic staff education.

Covid has changed the working world, perhaps forever, and employers need to adapt. Right now, businesses that need their staff to return to the office in at least a hybrid model, need to not only direct their resources towards actions that will reduce Covid risk but also show their staff what they’re doing and how it will keep them healthy and safe.