TITLE:
A Comparison of Relative Humidity between Two Swedish Buildings with Different Ventilation Solutions
AUTHORS:
Thomas Alsmo, Catharina Alsmo
KEYWORDS:
Hygiene, Hygiene and Health, Air Quality, Sick Building Syndrome (SBS), Particle Implication, Particle Measurements, Indoor Environment; Indoor Humidity, Indoor Temperature, Particle Size, Particle Amount, Physical Environment
JOURNAL NAME:
Journal of Environmental Protection,
Vol.7 No.6,
May
19,
2016
ABSTRACT: This
project is based on measurements of the parameter relative humidity, RH (%), in
two buildings: one with natural ventilation and one with mechanical
ventilation. Both buildings are located in central Sweden, which constitutes a
representative climate zone with respect to Swedish conditions. An important
factor for the indoor environment, which affects human health and well-being,
is the level of the relative humidity, RH (%). Research studies show that the
healthiest level should be in the range of 40% - 60%. Surveys have revealed
that about 70% of the employees at Swedish offices, schools and kindergartens
experience that the air is too dry during the winter season. Previous studies
show that the level of relative humidity in the indoor environment influences
the prevalence of respiratory infections and allergies. The purpose of this
study is to investigate how the relative humidity differ between the two
buildings, and if this may be a cause of the health problems that users are
affected by. During many years, users have complained about the environment in
the building with mechanical ventilation and that they suffer from health
problems. The method used in the study is air measurements of the two
parameters, relative humidity and air temperature in the two buildings using
data loggers. The indoor environment is affected by the outdoor climate and
therefore instruments are placed outdoors to record seasonal variations. The
measurements were carried out during the period October 2014 to September 2015
to include all of Sweden’s four seasons with completely different climatic conditions.
The results of this study show that the relative humidity in the mechanically
ventilated building is consistently significantly lower than in the building
with natural ventilation whatever the time of year and temperature indoors.
This study shows that mechanical ventilation in buildings affects the indoor
environment negatively with respect to human health during most time of the
year and this fact must be taken into consideration for the existing as well as
the planning of new ventilation systems.