Maritime Meteorology and International Navigating Limits (INL)

Maritime Meteorology and International Navigating Limits (INL)

There is steady development going on in the ports, docks, berths, and terminals. An unavoidable difficulty with any port directory is its sheer size. This results in many months passing between the input of the data and the actual publication date. There is no replacement for local information so if any port dimension or restriction is so important, communicate with a trustworthy agent. Frequently, the charter party stipulates One Safe Berth (1SB) when referring to loading or discharging port which places the onus upon the charterer to secure that the nominated berth is safe for the ship concerned. Nevertheless, the ship managers must operate ships efficiently; not to win lawsuits. It should not be ignored that although the ship manager is freed of many duties when a ship is on time charter rather than voyage charter, observing the safety of where the ship is ordered still has to be done. There is no substitute for experience in knowing about berth and no practical alternatives.  


Some regions of the world are ill-famed for heavy weather such as the North Atlantic in winter or Cape Horn at almost any time. Mediocre bad weather may increase the voyage time enough to erode the voyage profit. There are seasonal times of extremes of weather that can be damaging or deadly. In various parts of the world, storms have different names but basically, storms occur in regions of extremely low atmospheric pressure. Storms occur anti-clockwise in the Northern Hemisphere. Storms occur clockwise Southern Hemisphere. Storms develop over the sea and generate wind speeds averaging around 75 knots and gusts approaching twice that speed at times. Besides powerful winds, storms produce particularly heavy rain, and seldom does the wind cause tidal waves. The most damaging storms occur along the tropics of Cancer and Capricorn. Storms can put port facilities out of action and can devastate crops that would otherwise be ready for shipping.

Storms are common in the Southern Indian Ocean where they are naturally known by the meteorological name of Cyclones. Cyclones may be encountered from November to May. Infrequently, these storms can reach as far north as the Indian sub-continent they should not be confused with Monsoons which draw heavy rains with random gales between June and August. The gales are not of the same severity as cyclones but are violent enough to prevent loading and discharging operations at the port.

In the Gulf of Mexico – West Indies region the storms are named Hurricanes. Usually, hurricanes devastate crops, properties, and may take human lives. Hurricanes’ path can take them along the line of the Caribbean Islands, then on to the mainland where hurricanes do additional damage before being moderated by their passage over the landmass. The Hurricane Season is between June and November with the maximum recurrence between August and October. The Chinese name for heavy wind is Tai Fung from which the Westerners have derived the word Typhoon. In the Far East, numerous islands often suffer harsh financial loss when whole crops of rice, wheat, sugar, palm oil, etc. are damaged. Typhoons may occur any time between May and December with a maximum recurrence from July to OctoberAustralia experiences comparable storms that are known as Willy-Willies from January to April. Therefore, the Shipowner or Ship Manager should understand the risks of seasonal storms when planning voyages.


The cold Labrador Current which is responsible for the Newfoundland fogs also carries down icebergs which are pieces that have broken off the Polar icecap. Modern electronic systems in the ships make it more manageable to avoid iceberg perils.


Tides may have an impact on the safety of a berth. There is nothing unsafe about a berth to which the access is restricted such as by a sand bar at certain stages of the tide, so long as the berth itself allows the ship to be afloat at all times. Some coaster charter parties stipulate for Not Always Afloat But Safe Aground (NAABSA) but unless the charter is negotiated in such a way to ensure time counts while waiting for the tide, then the shipowner experiences that delay. This might be several days because during Neap Tides when there is the tiniest change, the depth may not rise adequately to permit access, and the ship has to wait for Spring Tides which could be as much as a week or more. In the coaster market, understanding tides can be even more critical. There is no point in ordering overtime to discharge fast or speeding at full speed to the loading port if the ship has to wait many hours for the tide to make before the ship can enter the berth.


Some regions in the world which are essential to shipping can have navigation prevented or even made inaccessible during winter months. For example, it seems reasonable for the farmers in the Canadian plains to deliver their grain for export to Churchill in the Hudson Bay but navigation is only possible there for the four (4) months of July-October. The St. Lawrence Seaway linking the Atlantic Ocean to the Great Lakes allows ocean-going ships to reach deep into the heart of the North American region but ice blocks this route from December to April. Weather forecasting has been reasonably reliable and there have not been any cases of large numbers of ships being trapped in the Great Lakes by an unanticipated freeze-up. The Baltic Sea becomes ice-bound from November to March and notwithstanding the sophistication of the ice-breakers, some of the ports are closed during the depths of winter. In some circumstances, there are quite attractive freight rates to be collected for late-season cargoes in ice-blocked regions but the risks have to be precisely estimated.


Fog is always associated with calm circumstances whilst at sea considerably mild winds may be involved. Sea Fog is different from that experienced inland. The primary component for a sea fog is warm moist air blowing over a cold sea. Fog may occur anywhere, however, fogs are especially prevalent off Newfoundland, California, Bering Sea, Baltic Sea, and Hudson Bay.


Weather Routing Service

Weather Routing Service is a system to avoid not only catastrophic sea perils but also to utilize the information obtained from far more complicated weather forecasting to avoid any sort of heavy weather. When ships crossing the North Atlantic in winter, the first thought would be to take as southerly a route as possible. However, this might be quite wrong as the systems bringing harsh weather could just as simply be lurking along that southerly route while on the northern route favorable conditions prevail.

Weather Routing Services aim to inform the Ship Master what weather conditions are anticipated for the voyage including storms, ice, fog, swell, winds, etc. Furthermore, Weather Routing Services recommend a route that will avoid the worst weather conditions. The Ship Master frequently sends feedback about the conditions in the ship’s location. Such feedbacks from many ships gives the  Weather Routing Service meteorologists a tremendous of data linked with satellite observation enables them to keep their weather forecast thoroughly up to date. 

Today, Weather Routing Services have become so successful an aid to faster and weather-damage-free voyages that it is customary for Time Charterers to insist upon Weather Routing Service information being received for all voyages undertaken under the time charter. Furthermore, Weather Routing Services can give unbiased data for a ship’s speed and fuel consumption performance under a time charter.



A load-line is the greatest depth to which a ship may be loaded. A load-line differs depending upon:

  1. Density of the water
  2. Time of the year
  3. Region (Load-line Zones)

The density of water is simply that if the ship is loading in freshwater, the ship can load to a greater depth because when the ship enters the sea, the greater density of saltwater will lift the ship to her saltwater load-line.

The time of the year is concerned with the ship having a higher freeboard for safety in wintertime when more turbulent weather may be confronted. Therefore, the highest freeboard is required Winter North Atlantic (WNA). Load-line is also called Plimsoll-mark. Politician Samuel Plimsoll persuaded the British government to take measures for the safety of life at sea by adopting the statutory marking. Load-line Convention devised a system of classifying the world into zones to correspond to the lines on the Plimsoll-mark. On the load-line map, there is a wide band around the world extending several degrees on either side of the Equator, marked T (Tropical Zone) which allows the deepest draft. Logically, the additional depth means more cargo and so more freight income. Sailing between Europe and North America in winter means loading to the lowest load-line mark Winter North Atlantic (WNA) where winter limitations are commanded from October to April. Long voyages are expected to involve more than one zone. Therefore, Shipowners and Ship Managers need to have a picture of the load-line zones in their minds. The foremost influence of load-line zones is on bunker planning. Ship Manager makes bunker planning to take full advantage of the load-line zones. Ship Manager should be careful if a ship is to load right down to the Tropical Marks (T) at a port on the edge of the Tropical Zone and then steam to the Winter North Atlantic (WNA) zone without having burnt off enough bunkers to bring the ship up to the Winter North Atlantic Marks (WNA). Even arriving with the Winter North Atlantic Marks (WNA) clear may not be enough. Port State Control (PSC) Surveyors can easily estimate from the ship’s Deadweight Scale whether or not the ship has nevertheless been sailing through winter zones with the appropriate mark well submerged. Ship Master may face heavy fines and an overloaded ship is technically unseaworthy. Therefore, an overloaded ship’s insurance cover could be void.


International Navigating Limits (INL)

The International Navigating Limits (INL) define the geographical limits within which ships can operate without incurring additional insurance premiums from Hull and Machinery (H&M) and other relevant underwriters. International Navigating Limits (INL) are, as a result of general agreement amongst Marine underwriters, incorporated into Hull and Machinery (H&M) insurance policies. Clause 34 of the International Hull Clauses imposes an undertaking upon the ship not to trade into icy regions during cold weather. However, International Navigating Limits (INL) can be broken if an application is made to the underwriters and the relevant additional premium (extra premium) is paid. The Institute Warranty Limits (IWL) were amended as of 1 November 2003. They have also been renamed and are now referred to as International Navigating Limits (INL).


International Navigating Limits (INL) Clauses

If Charterer orders the Vessel outside of the International Navigating Limits, Charterer shall reimburse Shipowner for any additional insurance premiums required by the Vessel’s underwriters as a consequence of such order.

The Vessel shall be employed in lawful trades within International Navigating Limits (INL) and within the Trading Limits as indicated in Box 16 for the carriage of lawful goods between safe ports or places where she can safely lie always afloat.


What is International Navigating Limits (INL)?

The original version of the Institute Warranties 1/7/76, which specified the trading limits of merchant ships, served its purpose well during that time, providing fair protection to the underwriters. However, as ship construction technology and navigational equipment advanced, the Institute Warranties started to become outdated.

Additionally, insured parties were burdened with additional premiums for navigating or calling in areas stipulated by the Institute Warranties 1/7/76, regardless of changes in the marine business environment. It became common practice to make frequent changes through attachments and endorsements to the Institute Warranties 1/7/76. The American Institute Trade Warranties of 1972 followed similar guidelines and also posed severe limitations.

In 2000, the Institute of Chartered Underwriters in London revised the Institute Warranty Limits (IWL) to address these issues. The new limits, referred to as the International Navigating Limits (INL) since 1 November 2003, took into account changes in ship size and quality, addressed climate changes, and allowed for wider global navigation.

The International Navigating Limits (INL) defined geographical limits within which ships could operate without incurring additional insurance premiums for hull and machinery and other relevant coverage. Operating outside the International Navigating Limits (INL), particularly in areas with significant hazards like ice, could result in ship damage and delays due to repairs. The trading limits clauses of charter parties often reference the International Navigating Limits (INL). It’s important to note that these clauses are provisions rather than warranties.

International Navigating Limits (INL) comprises a series of provisions that govern the permissible trading areas for a ship under English Hull Conditions as stipulated by the Institute of Chartered Underwriters.

However, it is important to note that not all shipowners adhere to the English Hull Conditions for insurance purposes, and the trading warranties may vary depending on the coverage terms. Therefore, it is advisable to verify the agreed trading warranties, particularly since charter parties often reference the International Navigating Limits (INL), which may not align with the Shipowner’s hull insurance policy.


Disparities between Institute Warranty Limits (IWL) and International Navigating Limits (INL)

To illustrate the disparities between Institute Warranty Limits (IWL) and International Navigating Limits (INL), let’s consider the INL76 clause 4, which entirely excludes the Bering Sea, whereas International Navigating Limits 2003 (INL 2003) allows for trading in the Bering Sea under specific conditions (i.e., during through voyages, provided the ship does not enter, navigate, or remain north of 54.5N, equipped with up-to-date largest scale navigation charts and compliant with certain GMDSS equipment standards). These relaxed restrictions, coupled with eased limitations in the Sea of Okhotsk, enable trans-Pacific voyages to be routed through a significantly shorter route, thereby saving time, fuel, and often encountering more favorable weather conditions than those found south of the Aleutian Islands. Consequently, this reduces overall greenhouse gas emissions.

Moreover, it is worth noting that all three conditions (Institute Warranty Limits 76 (IWL 76), AITW72, and International Navigating Limits 2003 (INL 2003)) are identical for the North American East Coast region, encompassing Greenland, St. Lawrence, and the Great Lakes waters.

When shipowners engage in fixing ships to ports or regions falling outside the International Navigating Limits (INL), they take into account the International Navigating Limits’ (INL) implications. If a shipowner intends to grant the charterer permission to trade beyond the International Navigating Limits (INL), it is crucial to collaborate with the relevant underwriters and ensure that the charter party incorporates the potential outcomes of such trading beyond the International Navigating Limits (INL). At this stage, it is necessary to consider a non-exhaustive list of contractual issues.

Furthermore, members must ensure that their insurance coverage aligns with the trading limits stipulated in the charter party. Some shipowners may have insurance coverage based on alternative trading limits, such as the American Institute Trade Warranties limits.

Breaching the International Navigating Limits (INL) involves navigating into or through areas that are either seasonally or permanently excluded without notifying the hull insurance underwriters or paying the additional insurance premium, which would render the ship’s hull insurance coverage void. Among the exhaustive list of permanently excluded areas are the Polar Regions, both North and South, typically above latitude 50˚ or 52˚.

The hull underwriters may permit ships to trade outside the Institute Warranty Limits (IWL) based on specific conditions and the time of the season. If ships are allowed to breach the warranties, meaning they are permitted to trade in the excluded areas, the underwriters will impose an additional premium for such voyages. Unless otherwise agreed, the premium is set for a round trip in and out of the excluded area. However, if the ship remains in the area and adds ports or engages in cross trading, the insurance coverage may become void unless the underwriters have approved such extensions. Vessels regularly trading in an excluded area or frequently calling at such an area can often choose to pay a seasonal cancellation fee instead of per voyage charges. The intention behind charging additional premiums is to maintain a low basic annual premium for hull cover. Only Shipowners electing to expose their ships to increased risks are required to pay the additional premium; otherwise, the burden of such exposure must be shared by all Shipowners, even those who opt not to subject their ships to icy or hazardous conditions.

Hence, the additional premium for breaching the trading warranties may be deemed substantial, but it is necessary to account for the heightened exposure. Winters can vary in severity, and certain hull conditions entail additional premiums specifically tailored for the Baltic region based on the prevailing ice situation. Other conditions often employ an advisory scale that is applied regardless of the actual ice conditions, leading to Shipowners or charterers lamenting the imposition of high additional premiums when voyaging in ice-free or minimally icy conditions. In severe winters, the charges for additional premiums may prove insufficient to cover potential claims. Past experiences have demonstrated that ice damage is directly correlated to the severity of the winter, the type of ice encountered, and the condition of the ship, including the competence of the officers.

It is important to bear in mind that Institute Warranty Limits 76 (IWL 76) and AITW72 are categorized as warranties, and breaching them without prior permission from the underwriters carries severe penalties. Conversely, International Navigating Limits 2003 (INL 2003) constitutes provisions rather than warranties, and as such, breaching them does not attract the same severe penalties.

It is quite common for a time charter to include a provision that allows the charterers to instruct the ship to sail beyond the International Navigating Limits (INL). Naturally, there is a rationale behind the establishment of these limits; venturing outside them can pose greater risks to the ship, thereby increasing the chances of damage. Generally, the time charterers are well aware of this fact and may propose a clause similar to the following in order to address it more explicitly:

“The charterers are hereby granted the authority, on occasion, to direct the ship to a port or location outside the current International Navigating Limits (INL), subject to payment of the additional insurance premium incurred.”

Such a provision is deemed acceptable as long as there are no grounds to challenge the extra premium demanded by the insurers, and as long as the ship remains undamaged. However, if the ship is indeed harmed, for example, by ice, the mentioned clause does not provide any basis for Shipowners to claim compensation from the time charterers for the loss of time required for repairs. This is particularly relevant when the damage is significant enough to impact the seaworthiness of the ship.

In such a scenario, the aforementioned clause would be of no use regarding the time allocated for repairs, and charterers may argue that the repairs could be postponed until a later date when the ship undergoes a survey or a similar assessment, provided that the ship’s seaworthiness is not affected. Consequently, the provision fails on two fronts: it does not specify that Shipowners have the discretion to obtain additional insurance as they deem necessary, nor does it specify that the time required for repairing the ship, resulting from compliance with the time charterer’s instructions to breach the International Navigating Limits (INL), should be borne by the charterers.


What is Institute Warranty Limits (IWL)?

The “Institute Warranty Limits” (IWL) is a term often used in marine insurance, specifically in relation to the coverage of ships and their movements. The Institute Warranty Limits (IWL) denotes geographical areas that are determined and specified by the insurance institute. Insurance cover for ships often changes when the ships enter or leave these geographical areas. This can have implications for the extent of the cover, the premium, or even the validity of the insurance.

The Institute Warranty Limits (IWL) is a way for insurers to control and manage their risk exposure. Some areas, for example, might be known for increased piracy, or are subject to severe weather conditions that would make them riskier to insure. It is a part of the insurer’s job to know these risks and adjust their policies accordingly.

If a ship were to move outside of the Institute Warranty Limits (IWL) without prior agreement from the insurer, it could result in the insurance policy being suspended or the claim being rejected. Hence, it is crucial for Shipowners and operators to be fully aware of the IWL stipulated in their insurance policy. They should communicate with their insurer about any planned or potential movements of the ship outside the Institute Warranty Limits (IWL).

It is important to remember that Institute Warranty Limits (IWL) can vary from insurer to insurer, as each company will have its own assessment of risk. Consequently, if a ship needs to travel to a location outside its current Institute Warranty Limits (IWL), a discussion with the insurer may result in an agreement to extend the limits for an increased premium or for a specific voyage.

It’s worth noting that Institute Warranty Limits (IWL) are determined by a committee of marine insurers who are members of the London Insurance market, specifically the London Underwriting Association and the International Underwriting Association.

The Institute Warranty Limits (IWL) are provided in a published list that delineates areas with specific latitudes and longitudes, often including reference to specific landmarks or named points. It is kept up-to-date to reflect changes in perceived risk due to factors such as political instability, piracy, war risk, and other elements that could potentially impact a ship’s safety or the likelihood of an insurance claim.

An insurer may allow a ship to navigate outside of the Institute Warranty Limits (IWL) under certain conditions. This usually involves a discussion and an agreement between the insurer and the insured, possibly involving an additional premium or specific terms. It is crucial that the insured does not unilaterally decide to navigate outside the IWL without first discussing it with the insurer, as it may render the policy void and the insurer may not cover any resulting claim.

Even within the Institute Warranty Limits (IWL), there can be areas that are deemed seasonal, meaning they are only covered during certain periods of the year when they are perceived as being less risky. These areas typically involve weather-related risks, such as ice in the North Atlantic.

Overall, understanding the Institute Warranty Limits (IWL) and how they apply to a specific marine insurance policy is crucial for anyone involved in the operation of a ship. These details should be considered when planning voyages to ensure that the ship remains insured at all times. As always, the specific terms and conditions of the insurance policy will prevail, so it’s important to read these documents carefully and consult with the insurer or an insurance professional if there’s any uncertainty.

The Institute Warranty Limits (IWL) were amended as of 1 November 2003. They have also been renamed and are now referred to as International Navigating Limits (INL).

We kindly suggest that you visit the web page of BIMCO (Baltic and International Maritime Council) to learn more about Institute Warranty Limits (IWL) and International Navigating Limits (INL).


Breaking Institute Warranty Limits (IWL) and International Navigating Limits (INL) in Ship Chartering

Breaking INL in Ship Chartering

In ship chartering, the Institute Warranty Limits (IWL) play a crucial role. These limits define the geographical areas where a chartered ship is permitted to operate under the terms of its insurance policy. The charter party agreement, which is the contract between the shipowner and the charterer, will often specify the areas where the ship can trade, and these should ideally align with the Institute Warranty Limits (IWL).

However, if for some reason a chartered ship needs to operate outside the Institute Warranty Limits (IWL), there could be significant implications. Breaking the Institute Warranty Limits (IWL) without prior agreement with the insurer can lead to a suspension of the insurance policy, potentially leaving the ship uninsured. In the event of a loss or damage during this period, the claim might be rejected by the insurance company.

The consequences of breaking the Institute Warranty Limits (IWL) can have a cascading impact on the charter party agreement as well. For instance, if the ship becomes uninsured, the charterer may be in breach of the charter party agreement, specifically the “lawful purpose” clause, which states that the ship must only be used for lawful purposes – and operating a ship without proper insurance could be seen as contrary to this.

Furthermore, under the “seaworthiness” clause in most charter party agreements, the shipowner has an obligation to provide a seaworthy ship. A ship without valid insurance may be deemed unseaworthy, potentially placing the shipowner in breach of the charter agreement.

Therefore, both the charterer and the shipowner need to ensure they understand and adhere to the Institute Warranty Limits (IWL). If the charterer anticipates the need to operate outside the Institute Warranty Limits (IWL), it’s crucial to communicate this to the shipowner in advance so that the shipowner can negotiate with the insurer for a possible extension of the Institute Warranty Limits (IWL). This might involve payment of an additional premium, but it could prevent potentially serious contractual and legal issues down the line.

In conclusion, breaking the Institute Warranty Limits (IWL) in ship chartering is a serious matter that could lead to significant legal and financial complications. It’s essential to manage these issues proactively to prevent potential problems.

If the ship violates Clause 1 under International Navigating Limits (INL) the Underwriters shall not be held accountable for any loss, damage, liability, or expenses arising from an accident or incident during the breach period, unless prompt notice is provided to the Underwriters upon receiving information about the breach. Moreover, any revised coverage terms and additional premium amounts required by the Underwriters must be mutually agreed upon


Breaching International Navigating Limits (INL)

International Navigating Limits (INL) delineates the geographical boundaries within which ships can operate without incurring additional insurance premiums from hull and machinery underwriters. Prior to 2003, these boundaries were referred to as Institute Warranties Limits (IWL), and the term Institute Warranties Limits (IWL) is still commonly used in charterparties today. It is advisable to update such references to International Navigating Limits (INL), as the revision involved significant changes in certain areas.

International Navigating Limits (INL) consists of two categories of excluded areas: those excluded seasonally and those excluded permanently. These areas present additional risks or heightened exposure to ships, particularly due to ice, which can pose extreme hazards. Even for ships with ice classification, there is a high risk of damage when navigating in icy conditions outside of International Navigating Limits (INL). Operating in these areas could result in ship damage and subsequent delays for necessary repairs.

When a ship breaches International Navigating Limits (INL) by entering or traversing one of the excluded areas without notifying the ship’s hull and machinery insurer, it goes against traditional practices. Hull and machinery underwriters typically manage the exposure to ice-related hazards through warranties, exclusions in the insurance policy, or agreed-upon special terms and premiums. Under English terms, if a shipowner violates an insurance warranty, any damage caused by ice would fall outside of coverage. However, the outcome would depend on the specific conditions outlined in the individual policy, as the Nordic terms differ from the English Institute Time Clauses (Hulls) (ITCH).

Authorization for designated regions stated in International Navigating Limits (INL)

The ship has the liberty to surpass the condition stated in the first clause under International Navigating Limits (INL), while the second clause shall not be applicable, on the condition that the prior consent of the Underwriters has been obtained, and any modified coverage terms and supplementary premium demanded by the Underwriters have been mutually agreed upon.


Charterers Liability Exposure under International Navigating Limits (INL)

A time charterparty frequently includes provisions that allocate risks when navigating in icy areas or provisions specifically mentioning Institute Warranty Limits (IWL) or International Navigating Limits (INL). Charterers should thoroughly review such provisions prior to instructing a ship to breach International Navigating Limits (INL).

Certain charterparties incorporate a provision allowing charterers to redirect the ship to a port or location outside International Navigating Limits (INL), with the payment of additional hull and machinery premiums.

In such cases, any damage to the ship would be covered by the Shipowner’s hull and machinery insurer, given that prior notice has been given before entering the conditional or excluded areas. However, the provision often fails to address the loss of time required for repairs. Unless additional wording regulates this matter, the provision does not support a claim from shipowners against charterers for the loss of time.

Other provisions grant charterers the right to breach International Navigating Limits (INL) but place all risks and consequences on the charterers. Considering the extreme hazards posed by ice, this would be an extraordinary risk for charterers to assume, particularly if the ship lacks ice classification.

Apart from provisions referring to Institute Warranty Limits (IWL) or International Navigating Limits (INL), charterers often face liability for ship damage and associated financial losses resulting from ice, either under a safe port provision or a specific ice provision.

Under an unsafe port provision, the charterer may be held liable for the consequences of instructing the ship to a port deemed unsafe due to ice obstructions. If any damage occurs to the ship, the charterer may be liable to the shipowner for such damage. The same liability applies if damage to the ship arises from the charterers’ breach of an ice provision by instructing the ship to an ice-covered area.

However, charterers must be cognizant of the possible repercussions on insurance coverage when chartering or engaging in trade with a ship that is ill-suited or unsuitable for the intended business. It is imperative for charterers to consistently conduct a thorough due diligence procedure concerning the existence of ice and potential dangers in the trading region.


International Navigating Limits (INL) Conditions 

The International Navigating Limits (INL), formerly known as Institute Warranty Limits (IWL), underwent revision and rechristening by the Institute of Chartered Underwriters in London, United Kingdom, in 2000. These modifications came into effect in November 2003.

The terminology IWL continues to be used in charter parties and associated documents. However, it is essential to update the references to International Navigating Limits (INL) due to significant changes in certain areas.

To “breach” or “break” the International Navigating Limits (INL) entails navigating into or through areas that are either seasonally or permanently designated as “excluded areas” without informing the hull insurance underwriters and neglecting the payment of the additional insurance premium. Such actions will render the ship’s hull insurance cover null and void.

  1. Seasonally Excluded Areas
  2. Permanently Excluded Areas


Permanently Excluded Areas

Areas that are permanently excluded encompass the Polar Regions, both North and South, typically situated above a latitude of 50˚ or 52˚. Additionally, the St. Lawrence Seaway, Great Lakes, Aleutian and Queen Charlotte Islands, as well as the Bering Sea, are permanently excluded with specific conditions.

Seasonally Excluded Areas

The areas excluded seasonally are usually found along the Northwest coast of North America (Alaska), Northwestern Russia, the Baltic, and the Northeast coast of North America (Gulf of Saint Lawrence and St. Lawrence River). During the winter season, these areas cannot be traversed under the conditions of summer hull insurance due to the presence of ice. Ice poses significant hazards to ships, and even if they are equipped for navigation in icy conditions, the risk of damage remains high. To sail through such areas, shipowners must obtain permission from their hull underwriters, often referred to as breaching the INL (International Navigating Limits). The International Navigating Limits (INL) comprises a set of clauses that dictate the permissible trading zones under English Hull Conditions, established by the Institute of Chartered Underwriters.

However, it is important to note that not all shipowners have insurance coverage under English Hull Conditions, and the trading warranties may vary based on the specific terms of coverage. Therefore, it is essential to verify the agreed-upon trading warranties, particularly since charter parties frequently make reference to the International Navigating Limits (INL), which may not align with the Shipowner’s hull insurance policy.

Navigating Limits under International Navigating Limits (INL)

Unless and to the extent otherwise agreed by the Underwriters in accordance with Clause 3 below, the ship shall refrain from entering, traversing, or lingering within the designated regions mentioned hereafter, at any given moment or, if applicable, during the indicated time frame (both days inclusive)

Area 1 – Arctic

  • North of 70⁰N

  • Barents Sea except for calls at Kola Bay, Murmansk, or any port or place in Norway, provided that the ship does not enter, navigate or remain north of 72⁰30’ N or east of 35⁰ E

Area 2 – Northern Seas

  • White Sea;

  • Chukchi Sea.

Area 3 – Baltic

  • Gulf of Bothnia north of a line between Umea (63⁰ 50’ N ) and Vasa (63⁰ 06’ N ) between 10th December and 25th May.

  • Where the ship is equal to or less than 90,000 DWT, Gulf of Finland east of 28⁰ 45’ E between 15th December and 15th May.

  • Vessels greater than 90,000 DWT may not enter, navigate or remain in the Gulf of Finland east of 28⁰ 45’ E at any time.

  • The Gulf of Bothnia, Gulf of Finland, and adjacent waters north of 59⁰ 24’ N between 8th January and 5th May, except for calls at Stockholm, Tallinn, or Helsinki.

  • The Gulf of Riga and adjacent waters east of 22⁰ E and south of 59⁰ N between 28th December and 5th May.

Area 4 – Greenland territorial waters

Area 5 – North America (East)

  • North of 52⁰ 10’ N and between 50⁰ W and 100⁰ W

  • Gulf of St. Lawrence, St. Lawrence River and its tributaries (east of Les Escoumins), Strait of Belle Isle (west of Belle Isle), Cabot Strait (west of a line between Cape Ray and Cape North), and Strait of Canso (north of the Canso Causeway), between 21st December and 30th April.

  • St. Lawrence River and its tributaries (west of Les Escoumins) between 1st December and 30th April.

  • St. Lawrence Seaway.
  • Great Lakes.

Area 6 – North America (West)

  • North of 54⁰ 30’ N and between 100⁰ W and 170⁰ W

  • Any port or place in the Queen Charlotte Islands or the Aleutian Islands.

Area 7 – Southern Ocean South of 50⁰S

except within the triangular area formed by rhumb lines drawn between the following points

  • 50⁰ S; 50⁰ W

  • 57⁰ S; 67⁰ 30’ W

  • 50⁰ S; 160⁰ W

Area 8 – Kerguelen/Crozet Territorial waters of Kerguelen Islands and Crozet Islands

Area 9 – East Asia

  • Sea of Okhotsk north of 55⁰ N. and east of 140⁰ E between 1st November and 1st June.

  • Sea of Okhotsk north of 53⁰ N. and west of 140⁰ E between 1st November and 1st June.

  • East Asian waters north of 46⁰N. and west of the Kurile Islands and west of the Kamchatka Peninsula between 1st December and 1st May.

Area 10 – Bering Sea Bering Sea

Except on thorough voyages and provided that:

  • the ship does not enter, navigate or remain north of 54⁰ 30’ N; and

  • the ship enters and exits west of Buldir Island or through the Amchitka, Amukta, or Unimak Passes; and

  • the ship is equipped and properly fitted with two independent marine radar sets, a global positioning system receiver (or Loran-C radio positioning receiver), a radio transceiver and GMDSS, a weather facsimile recorder (or alternative equipment for the receipt of weather and routing information) and a gyrocompass, in each case to be fully operational and manned by qualified personnel; and

  • the ship is in possession of appropriate navigational charts corrected up to date, sailing directions, and pilot books.