Loading and Unloading Requirements for Composite Containers (24)

Criticality: Medium
Progress: Not Addressed
Score: 24
DOT Relevance: §177.840

Description of Key Area

High pressure hydrogen storage technologies are being developed to address the low storage density—both gravimetric and volumetric—of gaseous hydrogen. Composite wrapped containers are susceptible to different types of external damage than all metal containers. For composite containers to be used for transportation applications, additional precautions may need to be specified. Additionally, composite containers are more susceptible to impact damage when empty as flexure of the composite fibers could cause fiber damage or breakage.

Discussion of Criticality

It is anticipated that as these storage technologies develop, their proponents will determine any unique conditions or procedures for container filling. It is also anticipated that as early products are brought to market, initial regulatory coverage will be via special permits which will likely require filling to be performed by the manufacturer or their designated agents, providing a level of control over the filling process through manufacturers’ developed practices.

Discussion of Progress

Most high pressure storage technologies are currently being developed for vehicular applications and are at the prototype stage. They are not yet in use for hydrogen transport. Progress was assessed as “Not Addressed”.

Recommendations

As development and deployment activities increase, initially the special permit process could be used to incorporate any special handling requirements during filling. With sufficiently wider deployment, requirements could be considered for incorporation into regulatory structure.