The apartments had hydronic radiant floor-heating
systems using hot water, which was installed and operated
independently of the ventilation system. In each
case, the floor was not covered by carpet, which could
affect the deposition and resuspension of particles.
Sampling was conducted both indoors and outdoors.
The instruments for indoor sampling were placed on a
small wagon in the center of the master bedroom and
living–dining room, sampling from a height of 1.2 m
above the floor. Outdoor air was sampled in front of
the outdoor intake of the mechanical ventilation system,
or on a balcony that was close to operable windows