What is a common method for detecting fuel theft?

The method of adding a foreign substance to the fuel is used as a technique to determine whether fuel is being stolen and to track unauthorized use. This method involves mixing a detectable agent into the fuel, making it possible to identify which vehicles or equipment are using the altered fuel. If the foreign substance can be traced back to specific locations or users, it can provide clear evidence of theft or misuse.

In contrast, while methods like conducting employee surveys, monitoring fuel purchasing patterns, and installing surveillance cameras can be useful for detecting irregularities associated with fuel theft, they may not directly identify the act itself as effectively as adding a foreign substance. Each of these other methods can contribute to a comprehensive approach to preventing theft, but the chemical tracing provided by the foreign substance offers a more definitive proof of unauthorized usage.