Hydrogen Sulphide (H2S) detected onboard vessel

A toolbox meeting was held on the bridge at which the risks associated with H2S were discussed.

The crew, equipped with gas detectors, started to investigate where the smell was coming from both inside and outside. No respiratory PPE was used. This was based on that the smell was noticeable all over the vessel, and that there was no indication of any gas before they started searching for the source. Last time vessel the same type of smell was experienced, this was caused by wind direction and ventilation from the sewage tank.

During investigation, a level of H2S of 170ppm was measured in the Grease Trap room. No gas was detected by gas detector in other areas onboard, only a smell. The H2S in the Grease Trap room came from the drain under the sink because the water trap was dry.

H2S was detected in the ventilation from the sewage/grey water tank, in the ventilation and not the surrounding area. The smell came from the sewage/grey water tank through multiple drains where water traps were dried out onboard in different areas.

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