Which action must a plumber take to install LP gas?

To install LP gas legally and safely, it is essential for a plumber to obtain an exemption care from the Railroad Commission. The Railroad Commission of Texas oversees the safety regulations and compliance for various substances, including liquefied petroleum gas (LP gas). This is particularly important because LP gas installations involve specific codes and safety measures that must be adhered to, ensuring that the installation complies with state regulations.

Obtaining this exemption care ensures that the plumber is recognized and approved to handle LP gas, thereby protecting both the contractor and the end-users. This step is crucial for ensuring that all safety protocols are followed and that the installation meets the required standards of safety and functionality. Without this exemption or approval, the plumber may not be legally able to perform these installations, which could lead to hazardous situations or legal issues.

The other options, while important in their own contexts, do not specifically address the regulatory requirement for handling LP gas installations in Texas. For instance, obtaining a permit from the city can be a part of the process but is not the primary action specifically required for LP gas installations. Similarly, completing additional training and passing a safety inspection are relevant but do not replace the need for the exemption care from the Railroad Commission.