Marine fuels and hydrogen sulphide

Report no. 8/13: The safe handling of petroleum cargoes and refined products that may contain hydrogen sulphide (H2S) is an important issue for the marine and inland fuel industries. Attention has refocused recently on H2S due to the revision of the ISO 8217:2012 specification for marine fuels which limited the maximum content of H2S in the liquid fuel to 2.00 mg H2S/kg fuel (2.00 ppmw).

This report summarizes issues associated with the presence of H2S in residual marine fuels including:

• Sources of H2S in petroleum products;
• Exposure levels for H2S in the vapour phase and the effects of exposure;
• Relationship between the H2S concentration in liquid fuel and in the vapour phase;
• Measurement methods for H2S in marine fuel and in the vapour phase;
• Interpretation of results and guidance on maximum H2S levels; and
• Guidelines for the safe handling of liquid petroleum products that may contain H2S.

Importantly, the report reinforces the need for safe handling procedures, training, and personnel protection when transferring or storing fuels that may contain H2S, rather than relying only on a measured H2S level in the liquid product.