Sparking during liquid transfer

Accident summary

The system involved in this near miss is a lined storage tank, lined pipework and lined tote. The totes were filled from the storage tank by pressurisation of the tank with nitrogen forcing the liquid through the pipework into the tote. The incident occurred as loading was nearly complete, and nitrogen was flowing through the pipework. An employee noticed 15 cm sparks between the metal straps on the tote and the metal lid holding the dip pipe and vent line. As the fluid was corrosive and not flammable, the consequences of this incident were not severe.

Failures in technical measures

• The metal frame of the tote was not adequately earthed so that a static charge generated within the liquid could induce sufficient charge on the metal frame to generate a spark between the metal frame and the lid.
• Earthing: temporary storage

References

'Sparks Fly During Process Transfer', Loss Prevention Bulletin, Issue No. 114, Dec 1993, p19, Institution of Chemical Engineers, ISSN 0260-9576.