TITLE:
Ventilation and Relative Humidity in Swedish Buildings
AUTHORS:
Thomas Alsmo, Catharina Alsmo
KEYWORDS:
Indoor Air Humidity, Ventilation, Hygiene and Health, Air Quality, Sick Building Syndrome (SBS), Indoor Environment, Indoor Temperature
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.11,
August
28,
2014
ABSTRACT:
An important factor for comfort ratio in
the indoor environment and affecting human health and well-being is the
relative humidity. Studies have shown that about 70% of the staff at Swedish
offices, schools and kindergartens experiences that the air is too dry during
the winter season. Studies show that the relative humidity in indoor
environments influences the incidence of respiratory infections and allergies.
Important factors for the air environment indoors is to limit the number of
airborne particles, since these are conveyors of both bacteria and viruses, and
to keep the humidity at a level above 40% and below 70%, making the survival of
viruses and bacteria minimized. Measurement results show that there is
significant difference in the relative humidity during the winter season
between the mechanically ventilated buildings with relative humidity levels
below 10% than in buildings with natural ventilation. An important issue is how
human health is affected by during longer periods and during much of the day
live in environments with low relative humidity. Several researchers have noted
that the incidence of respiratory infections increase during the winter when
people are exposed to long periods of low humidity indoors. This means that the
consequences of low humidity in the indoor environment should be considered and
evaluated in a completely different way than is done today.