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What is IMO 2020?

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IMO 2020 limits the amount of sulphur permitted in commercial ship fuel to 0.5% for ships operating worldwide.

Clearing the Air: Reducing Sulphur Emissions from Ships

In 2005, the International Maritime Organization (IMO) through the International Convention for the Prevention of Pollution from Ships, 1973 (known as MARPOL) began a process to limit sulphur emissions from commercial ships as part of a global effort to improve air quality.

The latest regulation – commonly called IMO 2020 or Sulphur 2020 – took effect on January 1, 2020 to limit the amount of sulphur permitted in commercial ship fuel to 0.5% for ships operating worldwide. The previously permitted sulphur oxides (SOx) emission level was 3.5%. Ships operating within designated emission control areas (ECAs) are the exception. Ships in ECAs must continue to meet more strict sulphur emission levels of 0.1%.

Figure 1: Global level of sulphur content permitted in marine fuels over time

Global level of sulphur content permitted in marine fuels over time
Reductions in Sulphur Emission Levels

Figure 2: Global Emission Control Areas

Global Emission Control Areas
(Source: Map adapted from

Why was IMO 2020 Introduced?

IMO 2020 recognized that the shipping industry was contributing significantly to world air pollution and that reducing the SOx from ship engines would provide major health and environmental benefits, particularly for people living close to ports and coastal areas.

The IMO expects the 2020 regulation to result in a 77% drop in SOx emissions from ships or an annual reduction of nearly 8.5 million metric tonnes of SOx.

Find out more about marine shipping and air pollution

The IMO received a study in 2016 that estimated 570,000 premature deaths between 2020 and 2025 could be prevented worldwide by implementing this additional sulphur restriction. It will also reduce the extent and amount of acid rain, which can harm crops and accelerate ocean acidification.

Can Ship Operators Avoid IMO 2020?

MARPOL regulations apply to all ships. Ships of all sizes are required to meet the 0.5% sulphur limit as of January 1, 2020. To ensure compliance, the shipping and fuel industries, along with regulators and other stakeholders, have been working to prepare for the transition.

The member states and flag states that are party to MARPOL Annex VI will monitor ships and enforce compliance, in accordance with IMO guidelines. Additional guidelines to support ship operators and fuel oil suppliers prepare to meet IMO 2020 were also developed.

Ships that violate the regulations may be barred from accessing ports as well as face fines and sanctions. If a ship is unable to obtain compliant fuel, its operators can complete a Fuel Oil Non-Availability Report (FONAR), which can be taken into account by the port State control authority when applying penalties. Even if accepted, the FONAR is not an exemption or easy way out; the ship will then have to remove any excess non-compliant fuel, a costly and time-consuming effort.

What is the Fuel Carriage Ban?

Enforcement of IMO 2020 is supported by a ban on the carriage of non-compliant fuel in effect on March 1, 2020. Ratified in 2018, the ban prohibits ships from carrying fuel with a sulphur content higher than 0.5% in their fuel tanks. Port State control authorities do not have to prove consumption of a non-compliant fuel; they simply have to check for its presence in a ship’s tanks to prove a violation. The only exception is ships equipped with exhaust gas cleaning systems (scrubbers) that remove sulphur emissions from ship exhaust before it is released to the atmosphere.

How Can Ships Comply with IMO 2020?

Ship operators have two main options to comply:

  1. Switch to a compliant fuel, such as a lower sulphur fuel oil (0.5% sulphur) or alternative fuel such as liquefied natural gas or methanol. Compliant fuels are available at most major ports.
  2. Install an exhaust gas cleaning system to allow the ship to continue using heavy fuel oil by removing or “scrubbing” the sulphur oxides emitted from the engine before the exhaust is released into the atmosphere.

Access to Compliant Fuel

Access to compliant fuel is essential for ships to meet the IMO 2020 regulation, as most ship operators intend to rely on compliant fuels rather than scrubbers. Before confirming the implementation date of January 1, 2020, the IMO commissioned a report that confirmed the capacity of the refinery sector to provide sufficient quantities of suitable marine fuel.

The compliant fuels must also meet IMO fuel oil quality standards to ensure that the safety of ships or performance of their engines will not be compromised. Additionally, the International Organization for Standardization (ISO) issued a new standard in September 2019 to specifically address quality concerns and considerations relating to the implementation of IMO 2020. Global refineries are responding to this new market opportunity by investing in new capacity, stockpiling compliant fuel, and increasing production.

How Will IMO 2020 be Monitored and Enforced?

IMO member states, such as Canada, are responsible for incorporating international regulations into national law and then enforcing ships’ adherence to those regulations. Flag states – countries where ships are registered – and port states – countries where ships enter ports – will be working together to enforce IMO 2020.

Port states enforce the provisions of MARPOL by monitoring vessels within their territorial waters, reporting non-compliance to the relevant flag state, and enforcing the regulations in accordance with national legislation.

Canada has implemented regulations related to IMO 2020 through its Vessel Pollution and Dangerous Chemicals Regulations.

Further, under the Marine Transportation Security Act and through the Marine Safety and Security Oversight Program, Transport Canada as the regulatory authority monitors every ship in Canadian waters through a number of mechanisms, including:

After IMO 2020: How Will the Shipping Industry Continue to Reduce Air Pollution?

The goal of IMO 2020 is to improve air quality by reducing sulphur content in emissions. It does not tackle the issue of greenhouse gases (GHGs) or climate change. However, the IMO began addressing GHGs produced by shipping in April 2018 with a vision to reduce those emissions to 50% of 2008 levels by 2050. The IMO has provided an initial strategy to reduce GHG emissions from ships and is developing mid- and long-term strategies.

The Global Maritime Forum, including 80 maritime, energy, infrastructure and finance companies working with government agencies and organizations like the World Bank, World Economic Forum and the United Nations Conference on Trade and Development, has set a more ambitious target – and formed an alliance called the Getting to Zero Coalition – to develop commercially viable ocean-going zero emission vessels by 2030. Additionally, some shipping companies have declared their intention to become carbon neutral by 2050.

As ships have an expected lifespan of approximately 30 years, the industry is facing a short window of time to make technological changes that can be integrated into ships to achieve these goals.

Learn More About:

Cutting sulphur oxide emissions from ships

Air pollution and marine shipping

How the marine shipping industry is regulated

Liquefied natural gas as an alternative marine fuel

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