Airflow Velocity and Sleeping (02-15-17)

Airflow velocity in a space influences how well we sleep there.  Morito and her team found that  “a higher air velocity of airflow disturbed human sleep more than a lower air velocity of airflow. . . . The mean air temperature, relative humidity, and mean radiant temperature in the rooms with both air conditioners were 26.4 . . . °C, 58 . . . %, and 26.3 . . . °C, and 26.4 . . . °C, 53 . . .  %, and 26.1 . . . °C for [A] and [B], respectively. The average . . . velocity of airflow was actually 0.14 . . . m/s and 0.04 . . . m/s for [A] and [B], respectively. . . . The subjects significantly felt more of the airflow and cooler at [A] than at [B] although comfort sensation did not differ significantly. . . . the number of times body movements, the number of times heart rate increased., and the number of times some sleep stages changed to the stage of wakefulness due to varying airflow in [A] were significantly higher than those in [B]. A higher velocity of airflow had a negative influence on sleep even though the average air velocity was less than 0.2 m/s [people are not aware of airflow at this low level].”  When higher airflow velocity was experienced, people slept more poorly.

Naomi Morito, Kazuyo Tsuzuki, Ikue Mori, and Hajime Nishimiya.  2017.  “Effect of Two Kinds of Air Conditioner Airflow on Human Sleep and Thermoregulation.”  Energy and Buildings, vol. 138, pp. 490-498.