Who manufactures and distributes copper tube according to specifications?

The correct answer is the American Society for Testing Materials (ASTM). This organization is known for developing and publishing technical standards for a wide variety of materials, including metals like copper used in a variety of applications such as plumbing, heating, and refrigeration. ASTM standards ensure that materials meet specific requirements in terms of quality, safety, and performance, which is crucial in industries that rely on compliance for safety and durability.

ASTM provides detailed specifications on copper tubes, covering important aspects such as dimensions, compositions, and testing methods. Because of this, industries can depend on ASTM's specifications to assure that the copper tubes they utilize will meet certain requirements for their intended use, ensuring reliability and efficiency.

While other organizations focus on different aspects of materials science, such as the welding or fire safety standards, ASTM specifically addresses material specifications and testing, making it the appropriate answer to the question regarding the manufacturing and distribution of copper tubes according to specifications.