<i>Effect of interior plants for CO</i>_<em>2</em><i> concentration, indoor air temperature and relative humidity in office buildings</i>

This experimental study investigates the influence of indoor plants on three aspects of air quality in office spaces: relative humidity, indoor air temperature, and carbon dioxide concentration. Employing a Latin square design, we rotated three different treatments across three offices over six time periods. These treatments included a control (no plants), a low volume treatment (five plants), and a high volume treatment (eighteen plants) of Nephrolepis exaltata (Boston fern). Air quality parameters were continuously monitored at five-minute intervals using Trace Gas Analyzers. Generalised linear mixed modelling (GLMM) was employed to examine the effect of each treatments on relative humidity, indoor air temperature and CO2 concentration. We found a significant positive association between the number of indoor plants and relative humidity. Median levels of relative humidity increased from 29.1% in offices with no plants to 38.9% and 49.2% in offices with 5 and 18 plants respectively. However, we did not find significant associations between the number of indoor plants and indoor air temperature or corrected CO2 concentration. Our research provides support for the use of indoor plants to increase relative humidity, which can have health benefits in dry climates, but does not provide support for using indoor plants to regulate indoor air temperatures nor CO2 concentration in office environments.