Compressed Natural Gas Certification Exam 2025 – Complete Prep Guide

The correct choice, composite materials or high-strength steel, is commonly utilized in the manufacturing of CNG storage tanks due to several key reasons.

Composite materials, often a combination of carbon fiber and resin, offer a high strength-to-weight ratio, making them ideal for handling the high pressure at which CNG is stored. This lightweight nature not only enhances fuel efficiency in transport applications but also contributes to safety, as they can withstand impacts and extreme conditions without significant weight penalties.

High-strength steel, on the other hand, has long been a traditional choice for CNG tanks due to its durability and ability to withstand high pressures, as CNG is typically stored at pressures ranging from 3,000 to 3,600 psi. The robust nature of high-strength steel also ensures long service life and reliability in various temperatures and environmental conditions.

In comparison, aluminum, while lighter than steel, does not provide the same level of pressure containment as high-strength steel or composite materials when it comes to gas storage and can be more susceptible to corrosion in certain environments. Plastic materials lack the structural integrity needed for high-pressure applications and would not be feasible for CNG storage. Copper is not commonly used for CNG tanks due to its higher density and cost, alongside its