A breath of fresh air


Building engineers and consultants keen to achieve the best results for their clients are placing an emphasis on the integration of effective CO2 monitoring and measurement, says Priva UK & Ireland sales manager Gavin Holvey.

Technical and trade media have contained a great deal of discussion in recent years about the contribution that key building systems – notably lighting – can make to the overall performance of a building and its personnel. But to date there has been rather less coverage of the role that monitoring and maintaining recommended concentrations of CO2 can play in keeping staff healthy and productive. 

The need for good, consistent air quality is not difficult to comprehend when one considers that the majority of workers spend about half their waking hours in their workplaces. Maintaining adequate indoor air quality, by both diluting indoor air pollutants and ensuring they are removed from the building through effective ventilation should therefore be a galvanising concern for building managers and engineers.

The vast majority of workplaces fall well within long-term (8-hour) exposure limits of 5,000 ppm, as outlined by the UK Health and Safety Executive. But this very much represents what might be termed the ‘outer limits’ of acceptability, with multiple studies revealing that complaints of drowsiness and poor air may rise notably with CO2 levels in the region of 1,000 to 2,000 ppm. Beyond 2,000 ppm, symptoms and complaints are likely to increase significantly, with employees more likely to register headaches, sleepiness, reduced powers of concentration, and even nausea.

A recent study produced by teams from Oxford Brookes University and LCMB Building Performance (with backing from EMCOR UK and Innovate UK) makes for especially insightful reading. Workplaces involved in the study were equipped with Internet of Things-enabled sensors to monitor CO2 levels, with employees sent numerical, proofreading and Stroop tests via email up to three time each day. 

With lower CO2 levels, employees’ test scores improved by up to 12%, whilst in one of the buildings tested people worked 60% faster with reduced CO2 concentrations. This led them to complete tests in a mean time of 8.2 minutes – compared with 13.3 minutes when more CO2 was in the atmosphere. 

The implications of sustained problems with CO2 for a company’s productivity, financial viability and even retention of staff could be long-term – particularly so if it’s a topic that is not on the building management team’s radar from the get-go, meaning that it could take a considerable period of time for it even to be detected as a problem. The good news is that, thanks to recent developments, it’s never been easier to implement CO2 measurement technologies.

Accurate and affordable measurement 

The availability of cost-efficient standalone solutions for the monitoring of CO2 levels has improved significantly over the last decade. Sensor-based systems make it possible to measure CO2 concentrations in multiple locations, and they can often be easily expanded and calibrated. Although such systems require occasional checks, most will work effectively for many years. 

For those with larger budgets, instruments that measure CO2 as well as temperature, relative humidity and other gases (for example carbon monoxide) are also available. Similarly, for the more ambitiously-inclined, it is also possible to invest in multi-room controller systems that make it possible to manage climate ceilings for heating and cooling, as well as administer induction and VAV systems, fan coil units and other primary room systems. With such a configuration it is very easy to achieve an overview – and overall control – of a working environment.

Once measurement systems have been successfully implemented, building managers can take other steps to improve CO2 levels. Reviewing room layout is one such consideration, with the possibility of improving air-flow as a result. 

Then there is the matter of newer buildings, where windows are often sealed and air-conditioned as standard. It is often the case that increased energy is expended on cooling via air-conditioning systems and the unnecessary creation of additional greenhouse gas emissions in the atmosphere. Indeed, close monitoring of CO2 levels during the EMCOR study revealed that fan speeds could be decreased by up to 50% without negatively affecting CO2 levels in the workplace.

Impulse to act

For companies who haven’t made CO2 a particular priority in the past, it makes sense for their building management teams to seek the guidance of vendors who have invested in specialist support capabilities, making it easier for them to specify, implement and monitor cost-efficient systems that can deliver lasting improvements.

Many of the leading names are also working to satisfy the requirements of building standards and codes of practice that have achieved worldwide traction. For example, the International WELL Building Institute’s WELL Building Standard – now generally regarded as the global tool for advancing health and well-being in buildings – offers extensive coverage of air quality issues, including CO2.

For companies who can show they have achieved alignment with such standards, there are obvious benefits in terms of their appeal to more health and environmentally-conscious employees. It can also mean a boost to general perceptions of a company both inside and outside its specific sector, and open up an additional angle for marketing and promotion.

Along with lighting, heating and noise, reducing CO2 levels is now one of the most effective ways in which employers can make a real difference to their productivity and the wellbeing of personnel. Now, more than ever, the tools they require are firmly within their grasp.