Current ISO standards will cover low-sulphur bunker blends

New 0.5% sulphur blends will be covered by the ISO 8217 specification. Credit: DNVPS
New 0.5% sulphur blends will be covered by the ISO 8217 specification. Credit: DNVPS

New blends of bunker fuels designed to comply with the 2020 sulphur cap will fit within the current ISO 8217 fuel standard, the International Standards Office (ISO) said today.

There had been concern among the shipping and bunkering industries that ISO 8217 would not encompass future 0.5% fuels, with the potential to cause significant safety issues if fuels become unstable or damage machinery.

“As these claims create quite some anxiety in the industry, the ISO working group, whilst respecting the anxiety raised, would like to reassure the industry that the General requirements of ISO 8217:2017 along with the characteristics included in Table 1 and 2 of ISO 8217: 2017 cover 2020 0.50% max Sulphur fuels in the same way as they cover today’s fuels including the 0.10% max. Sulphur fuels,” the ISO said.

ISO 8217 reflects the technical needs of machinery operations, “irrespective of the Sulphur content of the fuel oils,” including safety, the environment, onboard handling such as storage and cleaning, and combustion.

The ISO is also developing a Publicly Available Specification (PAS) that will provide guidance for the application of existing ISO 8217 rules to new 0.5% Sulphur fuels, in response to a request from the International Maritime Organisation (IMO).

With fuel oil blends expected to vary widely across the regions, vessels will have to look at the risk of incompatibility when using consecutive fuels from different ports and regions.

“Compatibility between different fuels cannot be guaranteed by the suppliers and it falls on the competency of the crew to manage this. Recognising that some degree of mixing of different fuel oils onboard the ship cannot be avoided, many ships today have already procedures in place to minimise commingling of fuel oils with bunker segregation being always the first option and are encouraged to evaluate further their segregation policy.”

There have been specific concern raised by CE Delft in the IMO fuel oil availability study concerning fuel oil blends containing H-oil bottoms, and the potential risk of instability if these fuels have not been properly blended. Reflecting that, as with fuels currently on the market, all future bunker fuels must meet the ISO 8217 total sediment potential requirement of 0.10 % maximum to remain stable.

“The consequences of fuel instability such as filter clogging and centrifuges blocking are well-known and it is to be expected that fuel oil blenders and suppliers must take careful note of these consequences ensuring this fuel characteristic is not overlooked and that the fuel is delivered to the ship as a homogenous and stable product.”