True or False: A main line valve is not required when the source shutoff valve is accessible from within the building.

The statement is true because, in some medical gas piping systems, if the source shutoff valve is easily accessible from within the building, a main line valve may not be necessary. The primary purpose of the main line valve is to provide an additional means of shutting off the gas supply for safety and maintenance reasons. However, if the source shutoff can be reached readily, and proper procedures are followed, the need for a main line valve may be bypassed. This means that trained personnel can safely operate the system without the added valve, making it an efficient setup when accessibility is not an issue.

It's also important to consider that specific codes or regulations may vary by location, so in practice, compliance with local regulations and safety standards is critical. Other options address specific scenarios or emphasize local regulations, while the statement remains relevant for circumstances that meet this particular accessibility condition.