# The Ability to Control VOC Emissions from Multilayer Building Materials
## 3 Results and Discussion
### Notes on the Limitations of the Research Method  
Due to the considerable length of the measurement series (480 h) and a large number of tested floor samples, the authors did not make duplicate tests. The test method adapted to the performed tests is mainly based on the standards [5; 6] of VOC measurements by the  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{2}{c}{**1-Butanol**} & \multicolumn{2}{c}{**Ethylbenzene**} & \multicolumn{2}{c}{**Butyl Acetate**} & \multicolumn{2}{c}{**m-p-Xylene**} \\ \cline{2-7}  & **Model** & **Exp.** & **Model** & **Exp.** & **Model** & **Exp.** & **Model** & **Exp.** \\ \hline D1 & 160 & 133 & 450 & 337 & 400 & 416 & 450 & 477 \\ W3 & 380 & 380 & 30 & 35 & 40 & 66 & 60 & 66 \\ \hline \hline \end{tabular}
\end{table}
Table 13: Comparing the \(C_{480\,h}\) (ug/m\({}^{3}\)) observed from the emission profiles by the model (17) and experimental values of four selected VOCs emitted from samples D1 tested in t = 29 \({}^{\circ}\)C and samples W3 tested in t = 33 \({}^{\circ}\)C (ACH \(n\) = 1.0 h\({}^{-1}\)).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Tested**} & \multicolumn{2}{c}{**Value of Parameter \(k_{1}\)**} & \multicolumn{2}{c}{**Value of Parameter \(k_{2}\)**} \\ \cline{2-5}  & **Min** & **Max** & **Min** & **Max** \\ \hline D1 & 0.007 & 0.02 & 0.001 & 0.002 \\ D2 & 0.007 & 0.01 & 0.002 & 0.003 \\ D3 & 0.006 & 0.02 & 0.001 & 0.002 \\ W1 & 0.004 & 0.01 & 0.0005 & 0.001 \\ W2 & 0.007 & 0.01 & 0.0005 & 0.001 \\ W3 & 0.01 & 0.02 & 0.001 & 0.002 \\ \hline \hline \end{tabular}
\end{table}
Table 11: Determined coefficients \(k_{1}\) and \(k_{2}\) of the equation C(\(t\)) (17) (TVOC) for each tested dry floor system D1–D3 (29 \({}^{\circ}\)C, RH = 50%) and wet W1–W3 (33 \({}^{\circ}\)C and RH = 80%) in the range of ACH \(n\) = 0.5–1.5 h\({}^{-1}\).  
chamber method and is within the scope of the authors' laboratory accreditation.The repeatability of the measurement results is estimated at 8%. Expanded uncertainty calculated with the coefficient k = 2, which gives a confidence level of 95%, is 24%.  
Another difference from the standardised test methods was the reduction of the VOC measurement time in chambers from 28 to 20 days. From the literature data, research experience in the field of VOC emissions from building materials and preliminary studies of the influence of temperature on the emission of volatile organic compounds noted that the most significant changes in emissions can be observed within the first 5-10 days from the beginning of the experiment. After this time, the VOC emissions rather stabilise. The assumptions of the experiment were developed with the idea of focusing on the most significant changes in the emission of volatile organic compounds under the influence of temperature, and not directly reflecting the tests compliant with the standard. The shortening of the research was also due to the obvious and practical reason which was the reduction of the time of very long and time-consuming research. The authors assume that the adopted approach does not significantly affect the correct interpretation of the results.  
The provided tests clearly indicate the influence of temperature on the VOC emission from floor systems, but this result obtained by the chamber method cannot be transferred on a 1:1 scale to real indoor situations in rooms with heated floors. The obtained results are just illustrative for a building level; however, with emissions of several thousand \(\upmu\)g/m\({}^{3}\) of TVOC, a corresponding value may be expected in real indoor environments. In this context, a mechanical ventilation system should ensure anair exchange rate above unity appropriate to the level of pollution, e.g., based on our results.