Cleanliness of air filters in the experimental passive house

An inherent element of the passive house is the system of exhaust ventilation in air supply. According to their class, air filters used in ventilation systems stop the contamination, but may also be the main source of secondary indoor contamination during long-term use.

IAQ in ambiente ospedaliero. Definizione di una metodologia di indagine in relazione all'inquinamento degli impianti aeraulici. Indoor air quality in hospitals. A methodology of sampling in relation with pollution of ductwork.

This paper presents the result of a research carried out on the valuation method of ductworks hygienic condition. Both the methodology and the results of the samplings carried out on the HVAC systems of ten hospitals are presented. For every HVAC system the following characteristics have been checked: typological and building features, air filters characteristics and maintenance programmes. Upon inspections openings carrying out, air dust concentration, dust on the duct surface, total and specific microbial concentration from the outdoor air inlet to the air intake have been sampled.