Clean air is vital for a healthy life. We spend an average of 90% of our time indoors. Thus, 90% of the air that we breathe is determined by the buildings where we spend most of our time. The way these buildings and their systems are designed and maintained determines their air quality and how it affects our health.
How many of us are sure that the air we are breathing every moment inside our homes, offices or any other buildings, is safe?
GBCI India and Saint Gobain Research India recently released a joint study, Healthy Workplaces for Healthier People, that evaluates the health performance of office buildings in India. The study evaluated 30 offices located in nine cities of India. Building data collected from project teams and professionals who work at the buildings, along with onsite measurements and inspection; and occupant feedback collected through online surveys were all analysed to determine whether the buildings were delivering healthy and comfortable spaces. Important parameters such as indoor air quality, lighting, access to outdoor views, thermal comfort, and acoustics, that define workspace quality, were evaluated.
Unhealthy indoor air is common
The study revealed that most offices are unable to maintain healthy indoor air quality. Out of the 30 offices studied, only one had all the indoor air contaminants within limits prescribed by standards.
CO2 levels, which are generally used to evaluate the ventilation adequacy of any space, were found to be higher than the recommended threshold in 75% of the office spaces, indicating inadeqaute ventilation. Poor maintenance of the ventilation system and incorrect operational practices led to reduced fresh air intake resulting in pollutant build up indoors. In some of the offices studied, it was observed that due to high outdoor air pollution, the building operators shut off outdoor air intake as a measure to reduce the entry of outdoor pollutants inside the space, unaware of the resulting increase in the levels of indoor pollutants.
Are buildings prepared to filter outdoor pollutants?
Ambient air pollution is a critical health concern in most urban areas of India and unless buildings are adequately equipped to filter outside air, outdoor air pollutants can enter the spaces unchecked and become the most significant source of indoor air pollution. Study data showed that 67% of the offices had NO2 levels higher than the recommended threshold. NO2 from outdoor traffic entering through ventilation and infiltration was found to be the most likely cause of higher levels indoors. Chemical filters that can remove NO2 from outdoor air were found in only 10% of the spaces. The concentration of particulate matter was higher than the threshold in 63% of spaces. 40% of the spaces did not have filters installed to trap fine particulate matter (PM2.5), and in around one third of the spaces that did have fine particulate filters, poor maintenance of the filters was an issue.
Study findings show that in locations where outdoor pollution levels were very high, a well-maintained filtration system with fine filters (MERV 13 or above) or electrostatic precipitators was effective in filtering out PM10 until outdoor PM10 levels were in the ‘very poor’ category or lower, and PM2.5 when outdoor levels were ‘moderately polluted’ or lower. However, in case of extremely high outdoor PM levels, even though the filtration system was effective in reducing the indoor levels considerably (in one case from outdoor PM10 levels of 733 μg/m3 to 76 μg/m3 indoors) it was not able to achieve the indoor PM level as per the standard.
Therefore, in regions where outdoor pollution is exceptionally high, outdoor air intake needs to be regulated and additional filtration technologies should be considered to keep particulate matter within healthy levels in indoor spaces.
How do employees feel about their workplace indoor air quality?
Even though on-site measurements showed that most workspaces had unhealthy air quality, 68% of the surveyed occupants reported satisfaction with the quality of indoor air. However, 45% of the survey respondents reported experiencing eye irritation, fatigue, dizziness, coughing and other symptoms which can be attributed to poor indoor air quality. The fact that high levels of indoor air contaminants were largely unnoticed by occupants indicates how critical it is to educate occupants on the impact poor indoor air quality has on their short and long-term health and the need for regular measurement and monitoring.
Given the COVID-19 pandemic, maintaining healthy indoor air quality is critical in ensuring workplace safety. Occupants will be wary of every breath of air shared with fellow occupants in enclosed spaces. Businesses and building owners should prioritize the evaluation of indoor air quality in workplaces and take necessary actions to improve it. Occupants’ well-being and safety should be the focus as we slowly transition to normalcy.
Read the Healthy Workplaces for Healthier People study to get more information on the health performance of workplaces in India, and to learn strategies to ensure occupant health is prioritized in these spaces.