## 3 Future Directions  
The existing well-accepted standards are very general and are not enough to support the need for an examination of the components of electrical power systems. For example, the standard [26] describes mainly the standard terms. The documents [27; 28] provide general principles for infrared thermographic testing in the field of industrial non-destructive testing. The standards [29; 30] focus on the instrument's features and properties. The following items are specified: objective lens, detector, image processor, display, thermal stimulation source, and accessories. The procedure for examining electrical equipment with infrared thermography is also very general and not fully related to high-voltage power engineering, unfortunately. A more constructive discussion and arrangements are needed to set a valuable standard. It is worth noting that the lack of such global standardization and the existence of too many standards or even drafts like in Poland [31] is very inconvenient when results from thermal imaging measurements in specific countries must be transferred and interpreted in another one.  
A good standard should be precise and cover the goals and interests of the various involved entities including the associations and standardization committees, installation operators, workers, end users, and even insurance agencies. This is clearly illustrated in the work [32] showing the insurer's point of view which tries to assess the financial risks of fire or malfunction. The insurance company disseminated its recommendation that is not fully consistent with other standards. There is even a discrepancy in vocabulary, and new aspects were pointed out as the extent of the damage and cost. For example, the following list is provided as an example for informational purposes in assessing the severity and possible actions. Four categories are mentioned:  
- \"Critical\"--failure of this component will have a crucial impact on operations;  
- \"Severe\"--failure is not expected to go beyond the tested component and would have a small impact on operations or the facility but repair costs could be significant;  
- \"Alert\"--failure is routine and repairs can be made easily and at a reasonable cost; cost is limited to labor and a few minor parts;  
- \"Advisory\"--helpful information based on engineering judgment.  
Unfortunately, in document [32], no temperature rise is proposed or specified for the easy classification to one of the above-mentioned categories, and other legal standards in a given country must support this guideline.  
Another open issue that defies attempts at standardization is data pre- and processing techniques for obtaining reliable and repetitive results. As stated in [8], with the increase  
\begin{table}
\begin{tabular}{c c l} \hline \hline
**Fault Class** & **Temperature Rise \(\Delta\Gamma\), K** & **Recommended Action** \\ \hline
1 & 0 < \(\Delta\Gamma\) < 10 K & There is no need to take any action, but observe \\ \hline
2 & 10 < \(\Delta\Gamma\) < 35 K & Eliminate the weak point at the next \\  & & shutdown—rectify if possible \\ \hline
3 & 35 K < \(\Delta\Gamma\) < 70 K & Eliminate the weak point during the next planned \\  & & maintenance but within a maximum of 6 months \\ \hline
4 & \(\Delta\Gamma\) > 70 K & Immediate elimination of a weak point \\ \hline \hline \end{tabular}
\end{table}
Table 5: Interpretation of the anomalies obtained from thermal imaging measurements according to the works [22; 25].  
in manpower cost and the expansion of the system scale, automation, and intelligence are the inevitable trends of the development of the IRT of power equipment. The problem is related to sophisticated techniques such as deep-learning methods [33,34] and relatively simple techniques used for image pre-treatment, image segmentation, target identification, temperature information extraction, fault identification, and diagnosis [9]. This is caused by the influence of chosen techniques and their parameters on the results.