A DOT tank is required to be recertified by visual inspection at intervals of _______ years after manufacture and every ____ years thereafter.

A DOT tank, which refers to a tank that complies with the Department of Transportation regulations for hazardous materials, is indeed required to undergo specific recertification procedures to ensure safety and compliance. A visual inspection is mandated at intervals of 12 years after the tank's manufacture, followed by subsequent inspections every 5 years thereafter.

This regimen helps ensure that the tank remains in a reliable condition and that any potential degradation, wear, or damage can be detected and addressed appropriately within a proactive timeline. Staying on this inspection schedule plays a critical role in safety management, especially for tanks storing or transporting hazardous materials, where the implications of failure could be severe.

The other options do not adhere to the established regulations. For example, choices that suggest shorter intervals fail to recognize that the initial 12-year period is the standard before it shifts to 5-year intervals, which is crucial for regulatory compliance. Understanding these timelines is essential for technicians who work with or inspect these tanks to ensure they maintain safety and adhere to federal guidelines.