SAFETY AND OPERATIONAL CONSIDERATIONS FOR COMPOSITE HYDROGEN AND CNG STORAGE CYLINDERS IN VEHICLES

Abstract

The increasing adoption of compressed natural gas (CNG) and hydrogen as alternative automotive fuels has intensified the demand for reliable and safe high–pressure storage technologies. Composite pressure cylinders offer an efficient solution for onboard gaseous fuel storage owing to their high strength–to–weight ratio, corrosion resistance, and favorable fatigue performance. This paper presents a comprehensive analysis of operational conditions, installation requirements, inspection procedures, maintenance practices, and safety considerations associated with Type–3 composite cylinders used for onboard storage of CNG and hydrogen in road vehicles. The study examines the effects of pressure cycling, temperature variations, environmental exposure, mechanical damage, and operational handling on cylinder integrity and service life. Particular attention is given to mounting systems, thermal pressure relief devices, inspection methodologies, and damage assessment criteria. Additionally, the paper examines fueling and defueling procedures, risk mitigation measures, and end–of–life management practices. The analysis highlights the critical factors affecting cylinder reliability and identifies key safety measures necessary for safe long–term operation. The findings contribute to improved operational reliability, risk management, and safety performance of modern alternative–fuel vehicle systems.