This report provides, for information purposes, a description of an un
usual event and the corrective actions undertaken by the Shell facilit
y involved. Shell and the authors hope that this information will help
personnel associated with other facilities understand a non-obvious f
ailure mechanism and take action to prevent their experiencing similar
incidents. While drawn from actual experience, the information provid
ed should be considered illustrative. Each company should review their
own facilities, materials or processes to determine the appropriate e
quipment and procedures for their own specific circumstances.