## 2 Materials and Methods
### Application Possibilities and Experiences of Micro-Fiber Based Insulations  
The use of micro-glass fiber materials as thermal insulation is well known, but it should be highlighted for better understanding. These materials can be used in buildings and for both industrial and vehicle engineering. They can be also used where the materials should be able to withstand high temperatures (\(\sim\)250-300 \({}^{\circ}\)C); for example, for insulating heating pipes transporting hot water or steam or for insulating furnaces [14]. Pipes are not only insulated to reduce heat loss. Several insulation methods are used which serve other purposes, such as safety, fire protection, sound attenuation, and condensation prevention. Thermal insulation coatings of pipelines have several elements that affect not only the efficiency of the system, but also the safety of their operation and utilization of the equipment [25]. Furthermore, they can be used as atic floors or dividing wall insulation between gypsum boards. It is reported that they can be used as shear wall insulation [26]. For choosing suitable places for these insulations, their thermo-physical properties as a function of temperature, density, mechanical load, thickness, and composition of insulating layers should be investigated. Moreover, analysis of the structure of the fibers is also vital [27]. These layers can be also used as the core of vacuum insulation panels (VIPs), due to their very lightweight and loose-filled structure [28; 29]. As previously presented by the authors, glass fiber materials are also suitable for sound insulation. It should be mentioned that the thermal stability of glass wool materials is higher than plastic foam, and their compressibility is greater compared to polystyrene types [30]. [PERSON] presented an extensive report about a comparison of the carbon footprint of different types of insulation materials. He revealed that low-density glass wool materials have about 1.494 kg CO\({}_{2}\) eq./kg carbon footprint, which is less than the values of both plastic foam and advanced materials such as VIP and aerogel. The author also stated that this material in use has the highest impact on the environment [31]. [PERSON] et al. [30] investigated the embodied energy and global  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Insulation Material** & **As-Received Density** & **As-Received Thickness [cm]** \\  & [kg/m\({}^{3}\)] st. dev. \(\pm\)3\% & **st. dev. \(\pm\)2\%** \\ \hline Pink & 6.8 & 4.08 \\ Yellow & 8.4 & 4.35 \\ Green & 10 & 4.7 \\ Orange & 16.5 & 3 \\ \hline \hline \end{tabular}
\end{table}
Table 1: The density and thickness of the as-received samples.  
warming potential of different insulation materials. The authors analyzed the insulation materials using CTGA standards for the cradle-to-gate method. They found that glass fibers have 134.17 MJ\({}_{\text{eq}}\) per f.u. energy consumption, and reached about 8 kg CO\({}_{\text{2 eq}}\) per f.u. of global warming potential. It should be mentioned that these values are higher compared to the values of other fibrous insulation such as cellulose or hemp [31,32]. Here, it should be mentioned that the environmental impact can be reduced and the circular economy approach can be adopted by using recycled glass during manufacturing [33].