What type of environment is required for CGI operation before an inspection?

A gas-free atmosphere is essential for CGI operation before conducting an inspection because it ensures the safety of personnel and prevents the risk of ignition or explosion. In environments where gas is present, there is an inherent danger associated with flammable gases that could lead to hazardous situations. By ensuring that the area is free of gas, inspectors can work safely and effectively, allowing for a thorough examination of the piping system without the added risk of gas exposure.

The other environments mentioned do not provide the necessary safety measures required for CGI operation. High humidity could affect equipment functionality and increase the risk of corrosion. A high-pressure environment poses risks related to potential leaks and failures in the system, while an extreme temperature environment may not be conducive to the operation of inspection equipment or could compromise safety. Thus, a gas-free atmosphere is the most crucial and appropriate condition for safe CGI operation prior to any inspection.