Onderwerp: Bezoek-historie

International Convention on Load Lines
Geldigheid:01-11-2021 t/m Versie:vergelijk Status: Geldig vandaag

Dit onderwerp bevat de volgende rubrieken.

Legend / Explanation of abbreviations:

  • ICLL: International Convention on Load Lines 1966
  • NSI: Netherlands Shipping Inspectorate
  • NVC: 'Nationaal Veiligheids Certificaat' / National Safety Certificate
  • RO: Recognised Organisation
  • SOLAS: the International Convention for the Safety of ife at Sea, 1974, and its protocol of 1988: articles, annexes and certificates, as amended
  • USCG: United States Coast Guard

Open top general cargo ships

With regard to the ICLL, article 8 and taking into account ICLL regulation 14, the NSI permits:

  1. existing open-top general cargo ships for which the keels are laid, or which are at a similar stage of construction, before the 1st of February 2018; and
  2. new open-top general cargo ships:
    1. for which the building contract is placed on or after the 1st of February 2018; or
    2. in the absence of a building contract, the keels of which are laid or which are at a similar stage of construction on or after the 1st of July 2018; or
    3. the delivery of which is on or after the 1st of July 2024; and
    4. ships, converted on or after the 1st of February 2018, with a keel laying date before the 1st of July 2018,

to be exempted from the requirement for cargo and other hatchways to be closed by weathertight covers of steel or other equivalent materials, provided that:

  1. a new open-top general cargo ship complies with the provisions of the Netherlands equivalent arrangement (GISIS no. XQ42482);
  2. an existing open-top general ship complies with the provisions of the Netherlands equivalent arrangement (GISIS no. XQ42482), with the following exceptions:
    1. In case the maximum hourly rate of ingress of green water in any one open hold determined from the model testing (measured in mm3/hour and converted in mm/hour) is more than 66 mm/hour, the following shall apply:
      1. The stability of an existing open-top general cargo ship in intact condition shall be (re)calculated in accordance with section 6 of the Netherlands equivalent arrangement (GISIS no. XQ42482); and
      2. An addendum to the existing approved stability documents shall be approved by the RO and placed on board.
    2. In case the maximum hourly rate of ingress of green water in any one open hold determined from the model testing (measured in mm3/hour and converted in mm/hour) is 66 mm/hour or less, the stability of an existing open-top general cargo ship in intact condition is not required to be (re)calculated. The existing approved stability documents may suffice;
  3. appropriate text shall be included reflecting paragraph 2.1 or 2.2 in the International Load Line Exemption Certificate issued to the existing open-top general cargo ship; and
  4. an International Load Line Exemption Certificate shall be issued with a reference to the Netherlands equivalent arrangement (GISIS No. XQ42482).

Multiple load lines (13-19)

With regard to the ICLL, article 3, paragraph (2) and regulation 2, paragraph (5), for a ship to which multiple load lines are assigned, the NSI authorizes the ROs to issue multiple Load Line Certificates, provided that:

  1. the stability information for the relevant statutory loading conditions corresponding to each load line mark, is approved and verified appropriately;
  2. the correspondent certificates are placed on board;
  3. the ship’s safety management system is revised and updated accordingly for multiple load line assignment, entailing at least the following points:
    1. One (1) Load Line Certificate is in use at any given time;
    2. Additional Load Line Certificate(s) is/are kept in a separated file and kept under the safe custody of the Master (in case of electronic certificates the certificates in use are clearly marked as (un-)active and visible for authorities either in the system or by written confirmation by the RO);
    3. Official entry shall be made in the log book for change in Load Line marking;
    4. the old load line mark is to be painted out with the same color as its background, and the new load line mark is to be painted in, in accordance with ICLL, regulation 8;
    5. the stability booklet on the bridge must be in compliance with the new load line mark and the International Load Lines Certificate; and
  4. other documentation (e.g. (damage) stability calculations) have been amended accordingly, where needed.

It is considered of importance that the change of ILLC, and satisfactory completion of this procedure, is reported to the RO of the ship (for Hull and Machinery). Such also to ensure change of electronic certificates/exemption.

Open top – tween deck – drainage

  1. Distance for the bulwark height

It is the opinion of the NSI that the situation with which a comparison can be made is the case of excess heights of bulwarks (refer to case a below) or a well (refer to case b below). The NSI during the first draft of the guidelines for open top has made an attempt to make use of the USCG interpretation for excess height of bulwark. As no consensus could be reached within the group it was decided to delete that part till there will be further experience or an actual request. At that time it was proposed to use the height measured from the freeboard deck to the top of the hatch coaming. The reason is that the ingress of water is, in our opinion, not influenced by the position of the tween-deck panel. The determining factors for the ingress of water (apart from the ship’s GM and seakeeping characteristics) are the freeboard deck in relation to the ship’s draft and the height of coaming. Having said that once water would flow into the cargo hold then the location of the top of the coaming in relation to the location of the tween deck panels would function as an obstruction for the water to flow out (case b below). Summarizing, based on the above there may be two functions:

  • Case a)       the height of the coaming may function as a protection from water to enter the cargo hold. In that case the distance measured should be from the freeboard deck to the top of  the coaming. This case resembles the case of excess height of bulwark. For that purpose ICLL, regulation 24(1) in conjunction with the interpretation of the USCG Load Line Technical Manual Ch. 3 can be used.
  • Case b)      the location of the top of the coaming may function as an obstruction for the water to escape. In that case the  distance should be measured from the tween-deck panel to the top of the coaming. This would lead to an unrealistic increase of the area. In that case the situation resembles more a well, where provisions of freeing should be made for the water to escape rapidly to the double bottom. For that purpose ICLL, regulation 24(4) may be used. Where reference is made to “actual height of bulwark” the height may be considered as twice the height of the maximum accumulated water inside the hold determined during the model test plus the amount of tropical rainfall multiplied by 3 hours. By multiplying the height by two, the heel of the vessel is accounted for (accumulation of water on one side)
  1. Effectiveness of freeing port area

The effectiveness of the calculated freeing port area (e.g. the total area of gaps between the tween decks) should be checked by calculating the time for drainage by direct calculation, for example in accordance with simple a Bernoulli calculation. The calculated time should be equal or less than 60 sec.
The reason why we request an additional calculation is to verify the effectiveness of the freeing ports. This check is also done for Load Line for the freeing port area in the bulwark.  The effectiveness can be checked in two ways: either with a time to flow calculation or an area check like this is done for the freeing port area in bulwarks required by ICLL, regulation 24(3).
The reason why we proposed to make use of the time to flow calculation, is because it is not easy to provide an equivalent for the free flow area in accordance to ICLL, regulation 24(3). The time of 60 sec is originating from SOLAS when calculating intermediate stages of flooding. When flooding is occurring within 60 seconds, it is considered instantaneous (ref. MSC.Res.281(85), Part B, Regulation 7-2.2).

  1. Assumed amount of green water to enter the vessel for assessing the freeing area openings between the tween deck hatches

The freeing area shall be calculated on the basis of twice the amount of water entering the cargo hold obtained from the model test, plus the amount of tropical rainfall multiplied by 3 hours.

The effectiveness of the freeing port area shall be verified by calculating the time to flow to be within 60 seconds. The amount of water to be used for that purpose shall be the maximum hourly rate of water ingress measured for the worst heading during the tests. 

  1. What if the freeing area is less than required

As there is no simple rule to assess how much water should be accounted for on the tween deck panel, it is essential that ample provisions shall be made for rapidly freeing the water from the tween deck. That means that the tween deck hatches shall be placed in such a way to ensure drainage of water. That follows the same principle as for the freeing port requirement included in the ICLL, regulation 24. After calculating the freeing port area as described above an additional check should be done by calculating the time for drainage. The way how to calculate that is up to the RO and the time for drainage should in no case exceed 60 seconds.

Guidelines for the assignment of reduced freeboard for dredgers

Exemptions on Load Lines for (a unit similar to) dredgers

With regard to the ICLL, article 6.2 and taking into account ICLL, article 25, the NSI may exempt:

  1. a dredger, as defined in the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 and DR-68/Rev.1), from ICLL, article 12.1 and a reduced freeboard be assigned, provided that the dredger complies with the provisions as set out in the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 or DR-68/Rev.1, as applicable) .
  2. a dredger, as defined in the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 and DR-68/Rev.1) without hatch covers (“open hopper”), from the ICLL, regulation 14, provided that the dredger complies with the provisions as set out in the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 or DR-68/Rev.1, as applicable).
  3. a unit similar to a dredger (e.g. a (non-self-propelled) hopper barge or a stone dumping ship) equipped with a cargo dumping system, as set out in paragraph 7.1 of the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 and DR-68/Rev.1), from ICLL, article 12.1 and a reduced freeboard be assigned, provided that the unit similar to a dredger complies with the relevant criteria as set out in the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 or DR-68/Rev.1, as applicable).
  4. a unit similar to a dredger (e.g. a (non-self-propelled) hopper barge or a stone dumping ship), without hatch covers, from ICLL, article 14, provided that the unit complies with the provisions as set out in section 6.1 of the ‘Guidelines for the assignment of reduced freeboard for dredgers’ (DR-67 or DR-68/Rev.1, as applicable).

Dredgers without assigned reduced freeboard

Dredgers without an assigned reduced freeboard fall under the relevant guideline DR-67 or DR-68 rev.1 as applicable, based on the understanding that DR-67 and DR-68 rev.1 are equivalent to the damage stability requirements of SOLAS, regulation II-1/4.

Dredgers with length less than 80 meters

Damage stability requirements for dredgers subject to DR-68 rev.1, are also applicable to dredgers with a length of less than 80 meters.

Dredgers, subject to DR-67, are in line with SOLAS, regulation II-1/4.  What means that with a length of less than 80 meters, they are not subject to damage stability requirements.

Application of SOLAS Chapter II-1, Regulation 9 (double bottoms in passenger ships and cargo ships other than tankers)

Notwithstanding the exemption for the damage stability of SOLAS, regulation II-1/4, for which the mutual understanding is that DR-67 or DR-68 rev.1 is equivalent to SOLAS damage stability, all other regulations of SOLAS are applicable. This means that SOLAS, regulation II-1/9 is applicable to dredgers. In the absence of a common interpretation on how to apply SOLAS, regulation II-1/9 to dredgers, a proposal should be submitted to the NSI for consideration.

Reduced minimum bow height (10-46)

With regard to the ICLL, regulation 39(3), for ships, including pontoons in the condition ‘manned working’, holding an NVC, as defined in Regulation Safety Seagoing Vessels article 3a, the NSI permits a reduction of the calculated minimum bow height, as required in ICLL regulation 39(1), as set out in Table 1.

Sailing Area             Maximum significant wave height Permissible reduction rate to the calculated bow height1
≤ 15 miles2 ≤ 4.0 meters 70 %
≤   5 miles3 ≤ 2.0 meters 50 %

Table 1

For ships to which the NSI has previously permitted a reduction of the calculated minimum bow height, as set out in Table 2, the reduction rates of the calculated bow height and the criteria, as set out in Table 2, may continue to be applied.

Sailing Area            Maximum significant wave height Permissible reduction rate to the calculated bow height1
≤ 15 miles2 7 Beaufort 70 %
≤   5 miles3 5 Beaufort 50 %

Table 2


1 Permissible reduced bow height

In percentage of the bow height calculated according to ICLL reg. 39(1) and reg. 39(2).

2 Sailing area 15 miles

Coastal waters whereby the offshore distance does not exceed 15 nautical miles and the sailing time from a safe harbor or anchorage shall be within 6 hours.

3 Sailing area 5 miles

Coastal waters whereby the offshore distance does not exceed 5 nautical miles and the sailing time from the port of operation, mentioned on the safe manning certificate, shall be within 12 hours and shall not be more than 6 hours from a port of refuge.

Transport of solid bulk cargoes

The NSI prohibits ships, flying the flag of the Netherlands, to transport solid bulk cargoes in ‘open-top’ conditions where the cargo and other hatchways are not closed by weathertight covers of steel or other equivalent materials.

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