Case study: Fatal Incident During Enclosed Space Entry

What happened?

On board a chemical tanker, an Able Bodied (AB) seaman wore a modified air supply equipment to enter a non-gas-free cargo tank to carry out cargo residue stripping in the pump well area. The AB was later found dead at the bottom of the said cargo tank staircase.

Why did it happen?

The ship completed discharging of NAPTHA cargo at terminal and shifted to anchorage. Tank washing, inerting, and gas-free operations were undertaken for a selected number of cargo tanks in preparation for the next load, while the remaining tanks were only well-drained and dried (unwashed tanks) and not gas freed.

During tank inspection from the tank dome, the Senior Deck Officer (SDO) observed a small amount of unpumpable cargo residue in the pump wells of the unwashed tanks. SDO was concerned of the unpumpable cargo residue contaminate the next cargo parcel and decided to strip the pump wells using a Wilden pump.

Tanks entries of the unwashed tanks by personnel were carried out without complying with the company’s enclosed space entry procedures. An AB entered one of the unwashed tanks alone to place the Wilden pump at its pump well. The AB wore a face mask with a hose coupling that had been modified to connect to the deck air compressor (see Figure 1).

The said AB failed to emerge from the tank and did not respond to radio calls. Although an emergency rescue operation was initiated, there were further delays in view of emergency response equipment such as a tripod was not kept on standby at the tank dome (see Figure 2: a re-enactment of the fatality incident).

Re-enactment of incident by ship’s crew

The AB was eventually lifted out of the cargo tank using the cargo hose crane. Despite immediate administration of cardiopulmonary resuscitation, the AB was pronounced dead by paramedics who were deployed thereafter.

Conclusion

Enclosed Space Entry Procedure

The Senior Deck Officer (SDO) executed an unauthorised operation that violates the company’s safety management system vis-à-vis enclosed space entry. This unauthorised operation led to a fatality on board.

Modification of the decompression setup

Considering the inconvenience of wearing the SCBA, the SDO instructed an unauthorised modification of the SCBA facemask (i.e. by connecting it to the air hose with compressed air supplied by deck air compressor), which was a deviation from its manufacturer’s specifications and intended scope of application.