Which regulation applies to transport containers built under special permit for CNG transportation?

The correct answer is based on the fact that transport containers built under special permit for CNG (Compressed Natural Gas) transportation must adhere to federal DOT (Department of Transportation) regulations. These regulations provide comprehensive guidelines that ensure the safe and compliant transportation of hazardous materials, including CNG.

DOT regulations cover various aspects such as the design, construction, and maintenance of containers, and they are crucial for protecting public safety during the transportation of compressed natural gas. This means that any special permits issued for transport containers specifically require compliance with these federal standards to mitigate risks associated with CNG transport, thereby ensuring that vehicles are properly equipped and that drivers are trained under regulated conditions.

In contrast, while the Texas Vehicle Code pertains to general motor vehicle operation standards, it does not specifically address the transportation of hazardous materials like CNG. ASME Guidelines typically relate to the design and construction of pressure vessels but may not directly pertain to the regulatory framework for transportation. State Environmental Regulations focus more on environmental impacts rather than the specific safety and compliance standards necessary for transporting hazardous materials. Thus, DOT Regulations is the most applicable choice in this context.