A field experiment with a controlled pretest-posttest design was conducted in three organizations. In each organization, two offices were selected. One month after the pretest, plants were introduced in one of the offices. The plants are aimed at increasing the air humidity in wintertime by 15%-points. After three months, a posttest was conducted. Temperature and air humidity were monitored for one year. In total, 75 employees participated during both pre- and posttest. Analyses of variance were conducted, with Time as within-subjects factor and Condition and Organization as between-subjects factors. Positive effects of the plants were observed for the visual appearance of the office, having positive feelings and self-rated functioning. A negative effect was observed for the need for recovery after a working day. No effect was observed for other measures, o.a. thermal comfort, ability to concentrate, stress level, social climate. The most striking result was a logistic regression for having reported sick during the previous three months (control = reference), adjusting for organization and sickness reporting on the pretest, showing a rather substantial effect of Condition: OR = 0.22 (0.05-0.93). At the moment, the study is being replicated at more locations, with a larger number of participants.
|Title of host publication||International Conference on Environmental Psychology 2019|
|Place of Publication||Plymouth|
|Publication status||Published - 2019|
|Event||International Conference on Environmental Psychology 2019 - Plymouth, United Kingdom|
Duration: 4 Sep 2019 → 6 Sep 2019
|Conference||International Conference on Environmental Psychology 2019|
|Period||4/09/19 → 6/09/19|