Your air conditioner (AC) may provide much-needed relief from sweltering temperatures in summer or warmth during chilly winter days. However, this popular home product can be surprisingly unhealthy, particularly when sleeping, for you.
As new study suggests that airflow from an air conditioner stimulates the human body while sleeping as it may increase the heart rate and impact sleep conditions even if the mean airflow velocity is lower than an insensible level.
The results indicated that the participants have significantly greater body movements, an increased heart rate and a higher frequency of waking in the room that has the AC with a mean velocity of 0.14 m/s. It implies that the cold airflow may have a greater impact on the overall sleep of the participants with lower physical strength or a greater sensitivity to cold.
According to researchers of Toyohashi University of Technology in Japan, some AC setting may have an unintentional negative impact on sleep quality despite the comfort the person feels. The research team, led by professor Kazuyo Tsuzuki, had the subjects sleep in two bedrooms using ACs set at different airflow velocities.
Then they made a comparison of the depth of sleep and body temperature control using electroencephalogram (EEG) measurements as well as subjective reporting by the subjects. In this study, a comparison was made on the influence of two types of airflow, mean velocity of 0.14 m/s (general AC) and 0.04 m/s (customised AC), both at a room temperature of 26 °C. The participants felt cooler with the higher airflow velocity during wakefulness and sleep. However, no significant difference was observed in the feeling of comfort, length of sleep depth, skin temperature, rectal temperature or sense of warmth or coolness in each subject before sleeping.
Air conditioning can have a number of negative impacts on health although it prevents us from feeling hot and stuffy. Air conditioning systems are also known to enhance the effects the illness that you may already be suffering from. The result is useful clue as to how to configure the airflow velocity of an AC to create a comfortable sleeping environment.
The new findings have been published and can be found in the journal of Energy and Buildings