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Structural failure of a transponder housing

Recently it was reported that the end of a transponder stored in an on-shore workshop blew off. The transponder had been in storage for a couple of months after being demobilised from the offshore site.

The cause was identified a result of seawater leaking into the housing during subsea operation – this reacted with the electrolyte in the battery pack and produced gas. Over a period the gas pressure built up causing the plastic retaining ring to fail which enabled the end to blow off. It was noticed that the vent bleed valve on the housing was closed.

The contractor involved has made a number of recommendations including:

  • Where practicable, a proper vent valve should be fitted to the highest point of the housing;
  • Caution should be taken when opening up housings;
  • Housings should be vented prior to shipping them back to storage or other worksites.

Safety Event

Published: 1 January 1999
Download: IMCA SF 01/99

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