# Mdpj _sciences_
## 4 Comparative Analysis of Experimental and Simulation Approaches
### Laboratory Tests
#### 4.2.3 Environmental Factors Influencing Purification
[59] tested plant species and substrate performance in a laboratory with a green wall, analyzing pH, total chlorophyll content, air quality, temperature, humidity, plant growth index, and leaf area, finding that species with high growth indices and coverage were most suitable. [PERSON] et al. [18] compared commercial green wall technologies in a laboratory chamber, using air sampling equipment and chemical analyses to determine pollutant reduction efficacy. Table 6 presents a comprehensive summary of laboratory tests conducted to evaluate the effectiveness of various green systems in mitigating different pollutants. The studies include a variety of green systems, such as plant species, active green walls, and green walls, tested in both indoor and outdoor environments. Each entry specifies the type of pollutant targeted, the green system used, the test site setting, and the specific pollutant detection methods employed. This detailed overview provides valuable insights into the experimental setups and methodologies used in controlled environments to assess the pollutant reduction capabilities of green systems. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Authors** & **Pollutant** & **Green System** & **Test Site** & \begin{tabular}{c} **Pollutant Detection** \\ **Method** \\ \end{tabular}  & **Performance Metrics** \\ \hline \multirow{4}{*}{[PERSON] et al. [52]} & \multirow{4}{*}{PM} & \multirow{4}{*}{Plant species} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} Laser nephelometer \\ (Graywolf \\ PC-3016A)—GrayWolf \\ Sensing Solutions, Shelton, \\ CT, USA \\ \end{tabular}  & \multirow{4}{*}{PM reduction: 65\%} \\ \hline \multirow{4}{*}{[PERSON] et al. [30]} & \multirow{4}{*}{PM, VOC} & \multirow{4}{*}{Active green wall} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} Photoionization detector \\ (ppbRAE 300)—RAE \\ Systems, San Jose, \\ CA, USA \\ \end{tabular}  & \multirow{4}{*}{PM reduction: 54\%, VOC reduction: 48\%} \\ \hline \multirow{4}{*}{[PERSON] et al. [31]} & \multirow{4}{*}{VOC} & \multirow{4}{*}{Active green wall} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} Photoionization detector \\ (ppbRAE 300)—RAE \\ Systems, San Jose, \\ CA, USA \\ \end{tabular}  & \multirow{4}{*}{VOC removal: 19.76–96.34\%} \\ \hline \multirow{4}{*}{[PERSON] et al. [10]} & \multirow{4}{*}{NO, NO\({}_{2}\), O\({}_{3}\)} & \multirow{4}{*}{Active green wall} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} Ecotech EC9841 nitrogen \\ oxides analyser; Ecotech \\ Serinus 10 02 \\ analyser—Ecotech, \\ Knoxfield, Victoria, \\ Australia \\ \end{tabular}  & \multirow{4}{*}{NO reduction: 50\%, NO\({}_{2}\) reduction: 45\%, NO\({}_{3}\) reduction: 60\%} \\ \hline \multirow{4}{*}{[PERSON] and [PERSON] [25]} & \multirow{4}{*}{VOC} & \multirow{4}{*}{Active green wall} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} Gas samplers (Laoying \\ 2020 Model)—Qinggado \\ Laoshan Electronic \\ Instrument Co., Ltd., \\ Qinggado, China \\ \end{tabular}  & \multirow{4}{*}{ \begin{tabular}{c} Formaldehyde \\ removal: 75\% \\ \end{tabular}  } \\ \hline \multirow{4}{*}{[PERSON] et al. [48]} & \multirow{4}{*}{VOC} & \multirow{4}{*}{Plant species} & \multirow{4}{*}{Indoor} & \begin{tabular}{c} GC-MS (Hewlett-Packard \\ 6890 GC/5973 \\ (now Agilent \\ Technologies), Santa Clara, \\ CA, USA \\ \end{tabular}  & \multirow{4}{*}{VOC reduction: 85\%} \\ \hline \multirow{4}{*}{[PERSON] et al. [49]} & \multirow{4}{*}{CO\({}_{2}\)} & \multirow{4}{*}{Plant species} & \multirow{4}{*}{Indoor} & \ \begin{tabular}{c} Portable gas exchange \\ system (Walz \\ GPS-3000)—Heinz Walz \\ GmbH, \\ Effeltrich, Germany \\ \end{tabular}  & \multirow{4}{*}{CO\({}_{2}\) absorption: 70\%} \\ \hline \multirow{4}{*}{[PERSON] et al. [55]} & \multirow{4}{*}{PM, O\({}_{3}\), SO\({}_{2}\), NO\({}_{2}\)} & \multirow{4}{*}{Plant species} & \multirow{4}{*}{Outdoor} &