Ultra-fine particles and air treatment systems

People are not only becoming more worried about polluted air in industrial environments. They are also concerned about increasing outdoor air pollution as a result of urbanization and growth of mobility.

Knowing that most people spend 80-90% of time indoor and to a large degree at work, it is very important to consider indoor air quality (IAQ). Given the health effect of airborne particles, it comes as no surprise that indoor ultra-fine particle levels have an effect on comfort, wellbeing and productivity of people in offices, manufacturing sites and public buildings like hospitals, schools, etc. This is especially true for people suffering from asthma, a group representing about 10% of the population in the western world.


In many buildings air-treatment systems have been installed to clean the outdoor air before it is distributed into the building. However, many filter types lack ultra-fine particle filtration capability. With today’s technology it is troublesome to assess the ultra-fine particle level in buildings and continuous monitoring is virtually impossible. Therefore it is difficult to gauge to which degree people are exposed to hazardous ultra-fine particles in buildings.

Indoor Air Quality Control

Air quality is influenced by the concentration of T, RH, CO2, VOCs as well as coarse, fine and ultra-fine particles. It is has been shown in scientific research that there is a direct link between indoor air parameters like T, RH, CO2, VOC’s and the comfort, wellbeing and productivity of people. Given the rising evidence of the effect of airborne particles, it is very likely that also this IAQ parameter will have similar effects.

As an example, in schools it is important to protect children against particles in view of the negative effect of air pollution on the development of the children’s lungs. For this reason building of schools near busy roads is under discussion. In hospitals, elderly care homes it is important to protect sensitive people such as those with asthma, COPD and heart problems. But also in commercial or office buildings, dire air quality outside and therefore potentially inside the building, have a negative influence on comfort, wellbeing and productivity of the office staff.

In practice buildings like schools, hospitals and offices are often located close to busy roads with the risk of high indoor particle levels. Furthermore indoor sources as smoking rooms, leaking printers and copiers or kitchens can add considerable amounts of airborne particles. A guaranteed low level of indoor pollution will improve wellbeing of the building residents and therefore contribute to the responsible image of the building owner or manager. For commercial buildings a low indoor pollution level will even directly increase the value of the property.

The problem is however that it is not easy to guarantee low indoor particle pollution as ultra-fine particles are microscopically small. One cannot just depend on filters having sufficient filtration efficiency and being properly installed and serviced. The unique Philips Aerasense technology now enables making ultra-fine particle levels visible. This solution offers real-time information for observation of ultra-fine particle concentration levels providing instant evidence of pollution levels and information for better filter management. In addition it provides quantitative justification for investments in filtration equipment and even data for the control of smart air treatment systems.