Effects of Green Plants on the Indoor Environment and Wellbeing in Classrooms—A Case Study in a Swedish School
Round 1
Reviewer 1 Report
The manuscript content is original, and it contributes to the knowledge on creating a healthy environment in schools and ventilated indoor environments. The manuscript is well organized but in part 3.4. Student well-being (397-410) I would recommend a short description of the results to the points in table 3 - Psychosomatic problems, Positive health, etc.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The paragraph from 47 to 58 lines would be modifed and moved to the "Discussion" section.
More foreign literature needs to be cited in the Introduction.
The abbreviation NASA should be explained (line 67).
When setting climatic conditions, the location of the school and classes should be explained in more detail. Does the control classroom have the same temperature, hours of sunshine? Are classroom A and the control classroom at different corners of the building?
Classrooms A and B have windows on different sides of the building (see photos), but in the sketch they are on the same side. Are both pictures (3a and 3b) actually needed?
Did they measure the opening time of the windows in all three classrooms?
There are three references missing in Student well-being.
Discussion is missing more foreign literature.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
The paper is an interesting study with measured and simulated data on the effects of green plants on the indoor environment and wellbeing in classrooms. The results are somewhat different from the literature review, and they are inspiring. However, the exploration of the measured data is not sufficient.
Here are some questions and suggestions.
*Method
- Regarding the design of the four green walls, is there a systematic evaluation to replace the descriptive presentation? For example, each design can be scored in terms of aesthetics, practicality, waterproofness, cost, etc.
- Is there a better way to obtain sick absence or truancy, e.g. retrieve the school's records on sick absence and truancy instead of asking the pupils?
- Regarding Figure 6, how to explain the increase in temperature of the green classrooms? I suggest comparing the indoor temperature between Classroom A/B without green walls and Control Classroom. In this way, the temperature changes before and after the installation of the green walls can be found.
- Regarding Figures 6 and 7, is there any data on temperatures and CO2 level change over time in the two green and control classrooms? In this way, we can see the changes in temperature and CO2 levels throughout the day.
- Figure 7 is difficult to read. How do you conclude that CO2 levels will be 10% lower after installing the green walls (Line 523)? How to explain one Peak of CO2 levels (of about 410 ppm) in green classrooms reduced? The suggestion from the paper is "probably corresponds to periods with unoccupied classrooms, e.g. during lunch and sports activities". Is it possible that it corresponds to the unoccupied period at night when the respiration of green plants increases the CO2 levels? Again, as mentioned in Question 4, it is better to have figures showing the change over time for better observation.
- For Figure 9, how much is reduced ventilation? Is there any measurement of indoor ventilation throughout the day? If not, how to determine the amount that has been reduced? Line 700 states that ventilation flow in buildings could be reduced. It lacks data to support this conclusion.
*Results
- For the questionnaire design, are other sources (e.g. TV news, chats in the family, covid, etc.) more influential on concerns about war and unemployment for young subjects? The questionnaire design can be better. In addition, the article mentioned that the rise in concerns about infectious diseases might be due to the outbreak of covid, not because of the green wall. It is a pity that such an external force interfered with the accuracy of the results.
- The interpretation of the measured data is relatively vague, and the control variables are not enough.
I recommend a revision, including adding the comparison data of classrooms A and B with the control classrooms when no green walls are installed.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
It is well noticed that the authors have replied to each issue carefully.
I agreed that some weaknesses are not possible to correct afterwards. Hopefully, the experimental design could be revised in the future.
Please strengthen the up to date reference part in environmental psychology, green building, environmental monitoring, etc.
Author Response
Dear reviewer,
We added a few more references from recent years.
If you have any additional specific references that you think could strengthen our manuscript even further we will be grateful if you could share them with us.
Please see also the attachment.
Author Response File: 
Author Response.docx
