TelestackPort of StocktonPort of South LouisianaGeneva DryTBA GroupCimbria
  • Geneva Dry
  • Port of South Louisiana
  • Vigan
  • Telestack
  • Van Aalst
  • Sailors Society

ClassNK publishes estimated leak frequencies of ammonia fuel

(Posted on 03/09/24)

ClassNK has published estimated leak frequencies of ammonia fuel from onboard components for ammonia-fueled ships, usable for risk assessment. The estimated leak frequencies were added as an appendix of 'Part C of Guidelines for Ships Using Alternative Fuels (Edition 3.0)'.

Ammonia, which does not emit CO2 when burned, is expected to be utilized as an alternative fuel for ships, and various studies and developments are currently underway toward the practical application of ammonia-fueled ships. Such ship design incorporates risk assessment, and risk assessment involves the consideration of the probability of ammonia leak from each component. However, statistical data of onboard ammonia leak have been extremely limited, therefore probability estimation of onboard ammonia leak was difficult.

Therefore, ClassNK, in collaboration with the Research Institute of Science for Safety and Sustainability (RISS), a department of the National Institute of Advanced Industrial Science and Technology (AIST), conducted probability estimation of the ammonia leak. Specifically, they used Bayesian method to estimate the probability of ammonia leak from each component combining with 1) the onshore ammonia leak frequency data in Japan extracted from the database of the High Pressure Gas Safety Institute of Japan, and 2) the LNG leak frequency data in LNG-fueled ships. Thus probability estimation using Bayesian method apply for the risk assessment of substances with few actual operation, such as hydrogen. This is the first time in the world to estimate the ammonia leak frequency in onboard component for ammonia-fueled ships.

By using this estimated leak frequency in onboard components for ammonia-fueled ships, a more reasonable and reliable risk assessment is achieved.

As part of the 'ClassNK Transition Support Services' that comprehensively supports our customers' smooth transition to zero-emission, ClassNK will continue to promote initiatives for the safe use of ammonia and other alternative fuels.

Latest News

Anemoi completes Rotor Sail installation on NS United bulk carrier

(Posted on 15/11/25)

Anemoi Marine Technologies, the UK-based leading designer of Rotor Sails for wind-assisted ship propulsion... Read more


LR and Marshall Islands certify Helm CONNECT electronic record books

(Posted on 14/11/25)

Helm Operations has announced that nine electronic record books within Helm CONNECT Logbook have been... Read more


Sailors’ Society launches increased support for Chinese seafarers

(Posted on 13/11/25)

International maritime welfare charity Sailors’ Society has announced a significant expansion... Read more


NORDEN signs two-year contract with US wood pellet producer

(Posted on 10/11/25)

NORDEN has signed a two-year Contract of Affreightment (COA) with Enviva to transport a significant... Read more


Algoma reports strong core results and continued fleet growth

(Posted on 10/11/25)

Algoma Central Corporation has reported its results for the three and nine months ended 30 September... Read more


Damen unveils Combi Freighter 5000 ICE

(Posted on 10/11/25)

Damen Shipyards Group has unveiled the latest platform in its successful cargo vessels portfolio. The... Read more


Wallem Group reaches a century in Hong Kong

(Posted on 04/11/25)

Wallem Group, a leading global maritime partner, is celebrating the centenary of moving its headquarters... Read more


INTERCARGO celebrates record membership ahead of 45th Anniversary

(Posted on 04/11/25)

The International Association of Dry Cargo Shipowners (INTERCARGO) is marking its 45th anniversary in... Read more


NORDEN reports net profit of US$26m in Q3 2025

(Posted on 04/11/25)

Net profit for the Group amounted to USD 26 million (DKK 166 million) in the third quarter of 2025,... Read more


ClassNK releases 'Guidelines for Onboard CO2 Capture and Storage Systems (Edition 2.0)'

(Posted on 04/11/25)

ClassNK has released 'Guidelines for Onboard CO2 Capture and Storage Systems (Edition 2.0)' first in... Read more


Sailors SocietyVan AalstViganBühler GmbH
  • Port of Stockton

Subscribe to our newsletter

Keep up to date with the latest global news in bulk cargo handling and shipping