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Field Evaluation of Topside Decompression Monitor (TDM) During Ships Husbandary Diving at SWRMC-NI

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Technical rept. 1 Jul-30 Sep 2010

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The Topside Decompression Monitor TDM was fielded to the Southwest Regional Maintenance Center - North Island SWRMC-NI dive locker under a NAVSEA waiver that allowed the TDMs decompression guidance to supersede that in Revision 6 of the Navy Diving Manual. The recorded depth-time profiles of SWRMC-NI ships husbandry dives were used to evaluate the benefits that the TDM provides. On the few testing occasions when a dive could exploit the additional no-stop time the TDMs guidance would allow beyond that prescribed by Rev. 6, that guidance proved to be unusable-either because early in the training period the Dive Supervisor was uncomfortable with it or because a hardware problem sensors clogging or the TDM not starting prevented it from being used. In a case were the Dive Planner could use information from the smooth log to avoid the 10 min of required decompression, the time required to confirm the result exceeded that required for decompression. This fielding of the TDM demonstrated that a switch from using Navy Diving Manual tables requires not only significant training time but also many dives conducted to enable personnel to become proficient in using it The long, shallow dives conducted by SWRMC-NI did not allow personnel to perform enough dives to quickly gain proficiency in operating the TDM. There was a savings of 34 minutes of decompression for a single dive. Real-time decompression calculations can afford operationally relevant savings in decompression time for surface-supplied diving-if the systems reliability can be demonstrated to Diving Supervisors. Operating procedures were expanded to redress situations identified during training.

Subject Categories:

  • Stress Physiology
  • Test Facilities, Equipment and Methods
  • Fluid Mechanics
  • Life Support Systems

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