Air duct
before cleaning

Air duct
after cleaning

Air duct
before cleaning

Air duct
after cleaning

Heavy polluted 
grilles in ceiling

Polluted grille

Polluted grille

Heavy polluted air duct

Heavy polluted air duct

Mould pollution
in air duct

Under floor plenum
before cleaning

Under floor plenum
after cleaning

Testo 454, measurering
T. & RH, CO₂
and air velocity

Microbiological
air sampler

Air borne dust sampler