Introduction Due to the advancement of the industry these days, the construction period, which is the convergence of the 2nd and 3rd industries of construction, has been shortened significantly. Yes, among them, the wiring between electric appliances, which is called the last construction of wiring, and electric appliances, through which a weak current flows, is a plug-in type. In order to save money, we will turn our attention to a simpler wire coupling mechanism. However, the key here is how much safety and durability are guaranteed. A fire occurred in the plugging device, which shows an example of this, and there was considerable property damage, and there were many voices of dissatisfaction with the consumers or consumers of the building.Accordingly, we want to present a direction for better selection of equipment and ensuring safety during installation by gathering the opinions of various electrical equipment officials in the field. Setting up several directions to eliminate fire safety and ensure safety I would like to put all my heart into this thesis. Also, if I dare to outline the order of enumeration, I will take a fire case to point out the wrong construction and tying of erroneous products, how to improve them, and even list the attitudes of engineers and workers for future construction and product completion. I would like to complete this thesis.