Variation in Radon Concentration Between Apartments in Housing Cooperatives

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The comments are inside the manuscript itself.

Comments for author File: Comments.pdf

Author Response

We would like to thank reviewer 1 for their careful review and for finding errors. We have taken into account almost all the suggestions for corrections.

Comment 1: Line 83. Radon priority areas is the preferred term.

Response 1: We have now used term ‘Radon priority area’ throughout the text.

Comment 2: Line 154. value instead of amount

Response 2:  We have corrected this.

Comment 3: Line 174. was instead of were

Response 3: The subject of the sentence, 'shape parameters values', is in the plural form, so we use the plural verb form, 'were'.

Comment 4: Line 206. This word should be deleted.

Response 4: It's deleted.

Comment 5: Line 352 and Line 353. Repeatability or reproducibility is connected to the precision of the result. Another word for correctness is in fact accuracy.

Response 5:  Thank you for noticing this; the explanations of the terms were exactly the opposite, but now they have been corrected.

Comment 6: Line 400. Cooperatives instead of companies?

Response 6: Cooperatives, it is now corrected.

Reviewer 2 Report

Comments and Suggestions for Authors

The resulting article is of great importance for radon safety in residential buildings in Finland. Overall, the work has interesting results that can complement the scientific problem field regarding radon.

I have several comments and recommendations for improving the manuscript.

1. It seems to me that it is necessary to provide information on potential radon sources for the study area (features of deposits, radium in soils, faults, etc.) in the form of a brief overview.

2. All appendices, except for statistical data, can be moved to the sections Materials and Methods, Results.

3. In the introduction, it is necessary to provide a more extensive overview of the features of radon level formation in apartments on the ground and multi-story buildings. Accordingly, this should be supported by references.

4. The objective of the study should be corrected. It should correspond to a more global agenda related to some scientific task or scientific problem related to radon. Your objective rather corresponds to routine monitoring.

5. It is not clear from the article whether the data were obtained by you or from the national register mentioned in the introduction. Please clarify this.

6. I did not find the 5th criterion for data filtration in the article. Can you add it?

7. Why were the winter months chosen for data filtration? This may be obvious to specialists, but for readers, an explanation with links is needed. Also, regarding premises on the ground, not on higher floors.

8. Cooperatives with low values ​​were excluded from the model, this is not discussed in any way in the discussion section. How should such cooperatives be dealt with in terms of forecasting?

9. The discussion should include the limitations of your research and model. They certainly exist. It is also necessary to compare your results with other similar works from recent years. They are available in specialized journals.

10. The conclusions should contain the results of your research in a condensed form. Your further plans may also be provided.

Author Response

We would like to thank reviewer 2 for their expert and thorough review. We agree with the reviewer on nearly all points and have therefore addressed almost all comments and suggestions for improvement.

Comment 1. It seems to me that it is necessary to provide information on potential radon sources for the study area (features of deposits, radium in soils, faults, etc.) in the form of a brief overview.

Response 1: We have added a paragraph at the beginning of the introduction that describes Finland's specific factors affecting radon concentrations in buildings along with the relevant references.

Comment 2. All appendices, except for statistical data, can be moved to the sections Materials and Methods, Results.

Response 2: We did not do this, as it is likely a matter of preference how detailed certain topics are addressed in the results section. Reviewer 2 is clearly an expert who can easily comprehend and master long and complex texts. However, our goal was to make it easier for the average reader and to move descriptions of some methods and results to the appendices.

Comment 3. In the introduction, it is necessary to provide a more extensive overview of the features of radon level formation in apartments on the ground and multi-story buildings. Accordingly, this should be supported by references.

Response 3: Text on the distribution of radon concentrations in multi-story buildings and the relevant reference has been added to the introduction.

Comment 4. The objective of the study should be corrected. It should correspond to a more global agenda related to some scientific task or scientific problem related to radon. Your objective rather corresponds to routine monitoring.

Response 4: We agree that the objectives were previously written inadequately. The last paragraph of the introduction has been rewritten to place our study in a broader perspective regarding its goals.

Comment 5. It is not clear from the article whether the data were obtained by you or from the national register mentioned in the introduction. Please clarify this.

Response 5: Clarification has been added at the beginning of the Materials and Methods section.

Comment 6. I did not find the 5th criterion for data filtration in the article. Can you add it?

Response 6: One of the criteria had been accidentally omitted from the list, although it was referenced in the text. This criterion has now been added to the list. We also felt it was necessary to provide a more detailed description of the omitted criterion's significance, so we added a brief comment on this in the text.

Comment 7. Why were the winter months chosen for data filtration? This may be obvious to specialists, but for readers, an explanation with links is needed. Also, regarding premises on the ground, not on higher floors.

Response 7: We included an explanation for why only the results from the measurement period were accepted for analysis. The description of the data on lines 143-145 states that the results are almost entirely from ground-contact apartments.

Comment 8. Cooperatives with low values ​​were excluded from the model, this is not discussed in any way in the discussion section. How should such cooperatives be dealt with in terms of forecasting?

Response 8: We have added a separate paragraph in the Discussion section, where we discuss the challenges of detecting variation in low radon concentrations.

Comment 9. The discussion should include the limitations of your research and model. They certainly exist. It is also necessary to compare your results with other similar works from recent years. They are available in specialized journals.

Response 9: The limitations discussed are: 1) the model is only applicable to ground-contact apartments, 2) the dependence of GSD on GM is unlikely and inconclusive, as well as new points 3) limitations for cooperatives with GM <20 Bq/m³, and 4) discussion on the impact of construction methods on concentration variation. Comparison with the results for other surveys has been added along with relevant references.

Comment 10. The conclusions should contain the results of your research in a condensed form. Your further plans may also be provided.

Response 10: A paragraph has been added to the conclusion, where the main findings are summarized briefly.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The received version of the manuscript contains most of the comments I have indicated. I believe that the article is suitable for publication in the journal.

As a request, for consideration by the authors of the article, I would recommend adding references to studies of residential buildings on the first floors in harsh climatic conditions with a pronounced continental climate. This will emphasize the importance of your work for areas with long and low winter temperatures. Also add references to works that assess the role of house architecture in the penetration and retention of radon indoors. This is especially important for new buildings with good insulating properties.

Thank you and good luck!

Author Response

A humble thank you once again for these comments, Reviewer 2. You have done a tremendous job in improving the manuscript.

Finland's climate is comparable to the boreal continental climates of Sweden, Russia, the Baltic countries, and Canada. However, comparing the radon concentrations in these countries to those in regions further south does not necessarily lead to the conclusion that a cold climate results in higher indoor radon levels. For example, in Latvia, radon concentrations are generally low because the bedrock predominantly consists of Paleozoic and Mesozoic sedimentary rocks with low uranium content. In contrast, Sweden exhibits similar indoor radon levels to Finland, as both countries have abundant igneous rocks with higher uranium content compared to sedimentary rocks. Russia and Canada, on the other hand, are vast regions, comparable in size to Europe, making it difficult to generalize radon concentration comparisons in these countries. The impact of temperature differences on pressure gradients is well documented and can be found, for example, in reference [3].

Regarding the significance of building foundations and radon prevention measures in indoor radon concentrations, we have added reference [4] to the article. This study discusses the impact of various subfloor solutions and radon mitigation measures on indoor radon levels. The study was conducted in Finland in 2016 and covered 1,332 new residential buildings. The objective of the present research was not so much to analyse the influence of construction methods on variations in radon levels between homes but rather to quantify the magnitude of this variation. Therefore, we do not address construction techniques more extensively in our manuscript.

And once again, many thanks, and a wonderful start to the year 2025!