WATCHOUT - A P&I Guide to Preventing Pollution at Sea

07 Jun 2023 The Navigator

Captain Akshat Arora, Senior Surveyor at NorthStandard, examines the risk to the marine environment posed by pollution from a P&I point of view, and how ships can play their part in preventing them from happening

The marine environment is vital to the health of our planet, and pollution from ships could potentially pose severe and longlasting effects. Over the last five decades, the International Maritime Organization (IMO) has prioritised the preservation of the marine environment by minimising the risk of pollution caused by ships, whether accidental or from routine operations. 

The International Convention for the Prevention of Pollution from Ships (MARPOL) was adopted by IMO in 1973 and was subsequently amended by the 1978 protocol. However, it was only in 1983 that the combined conventions entered into force.

Over the years, the scope of the MARPOL Convention has significantly expanded through a total of six annexes, addressing the prevention of pollution by oil, chemicals, other harmful substances carried by sea in packaged form, garbage, sewage, air pollution and emissions from ships. Certain sea areas within most of these annexes are designated as “special areas” where a higher level of protection is required.

MARPOL is the primary regulation that deals with the prevention of pollution by ships. Other conventions address risks to the marine environment, such as control of harmful anti-fouling systems on ships (AFS Convention), prevention of the spread of invasive aquatic organisms carried by ships’ ballast water (BWM Convention), and the environmentally sound recycling of ships (Hong Kong Convention), to name a few.

Pollution incidents and P&I Clubs

Pollution incidents can potentially result in significant financial losses for shipowners. Therefore, liabilities in respect of pollution have become one of the most important areas of P&I (Protection and Indemnity) Club cover, both in terms of the amounts paid and the coverage needed.

From a P&I Club perspective, other than in cases of purely accidental escape or discharge of a pollutant, cover for pollution fines and associated expenses is only available on a discretionary basis. For a discharge to be accidental, there should be no intention to cause the discharge. Generally, there is no recovery in the event of any personal act, gross negligence or wilful misconduct.

To have any prospect of receiving money to cover damages from the Club, the shipowner would need to satisfy the board that all reasonable steps had been taken to avoid the event. This is a difficult test to meet and involves detailed scrutiny of the circumstances of the offence, as well as an assessment of the environmental policies and procedures in place.

Best practice checklist

The most effective way to reduce risk in this area is by employing operational best practices that:

  • place MARPOL compliance as the highest priority,
  • establish a ‘zero pollution’ and ‘no blame’ culture with open reporting of illegal practices,
  • ensure proper training is conducted on MARPOL requirements,
  • implement procedures/guidance on equipment control, tamper-proof measures, periodic testing, inspection and maintenance regimes, and
  • ascertain that this is regularly verified during internal audits and inspections


The Nautical Institute’s Mariners’ Alerting and Reporting Scheme (MARS) - - comprises a fully searchable database of incident reports and lessons, updated every month. If you have witnessed an accident or seen a problem, email Captain
Paul Drouin at and help others learn from your experience. All reports are confidential – we will never identify you or your ship.