Air Quality and Ventilation Hygiene Study Zentrum Schluefweg, Kloten

The project

Location: Kloten in the canton of Zürich
Client: Stadt Kloten (Kloten municipality)
Reason: Hygiene and health-related assessment of ventilation systems in place since the time they were introduced (1977)
Period: 2020


Zentrum Schluefweg in Kloten has an extensive ventilation system network unchanged since the time of its introduction, which is to be renovated in stages over the next few years. In order to ensure that no health risks were posed to the building users by the ventilation system in its current state, the quality of the air from the ventilation system was analysed by Econsens AG. To do this, the supply air in various rooms was checked for any microbial contamination, fine dust and the presence of synthetic mineral fibres,
and these measured values were compared with the hygiene requirements of the applicable standards and directives.
According to the hygiene requirements for building ventilation systems and devices, the quality of the supply air must not be worse than the air with which it is being compared (in this case, the outside air). The measurements performed were able to demonstrate that the quality of the air from the ventilation system was flawless from a hygiene perspective, thus ruling out a threat to building users.


Our services

  • Analysis of the supply air in different rooms for airborne germs, bacteria and fine dust, including a reference measurement of the outside air.
  • Implementation and evaluation as per the current directives – SWKI VA 104-01 (VDI 6022 Sheet 1).
  • Visual inspection of the ventilation system network.
  • Measurement of the concentration of synthetic mineral fibres (SMF) in selected spaces (measurement as per VDI 3492).
  • Definition of measures for ensuring flawless room air quality right through to total renovation of the ventilation system.


  • Representative sampling of facilities in the extensive system network.
  • Prevention of false air additions through the room air with various and sometimes difficult-to-access air outlets.
  • Risk assessment for the user and the definition of short-term and medium-term measures.

Project manager:

Pascal Diefenbacher Divisional manager for indoor air quality
Dr. sc. Environmental Sciences (Federal Institute of Technology) +41 44 839 47 97 More

Raphael Rapold Project manager: Indoor air quality
MSc. economic chemistry +41 44 839 47 90 More