DNV has published the July 2023 edition of the rules for classification of ships

The July 2023 edition of the rules for classification of ships was formally approved on June 14th, 2023 by DNV Group CEO Remi Eriksen and will enter into force on the 1st of January 2024.

General information

The main changes to the rules cover new and revised class notations, implementation of external requirements from organisations such as IACS and IMO, as well as general updates based on market and technology development.

“The new and updated rules are aligned with international regulations and are expected to improve the safety and reliability of ships,” said Geir Dugstad, Technical Director for DNV Maritime.

In addition to the changes in the rules for ships, smaller changes have also been made to the rules for classification of underwater technology and high speed and light crafts.

The rules for classification of offshore units will be presented separately.

Customers can contact their local DNV office for more information on the changes.

The rules may be applied to projects contracted before the entry into force date, upon agreement between parties. 

DNV publishes one main rule edition every year. The next main rule edition is scheduled to be published in July 2024. From time to time, additional amendments may be made to the rules. These amendments will be announced in the Rules and Standards Explorer

Summary of the main changes in this edition

Topic DNV-RU-SHIP Main updates

Topic

Scantlings – minimum requirements    

DNV-RU-SHIP

Pt.3 Ch.1 Sec.2

Main updates

Opened for scantlings below specified minimum requirements on certain conditions being fulfilled

Topic

Fuel tanks type C

DNV-RU-SHIP

Pt.3 Ch.11 Sec.2

Main updates

Introduced requirements for foundation/supporting structure

Topic

Special hull structures

DNV-RU-SHIP

Pt.3 Ch.10 Sec.6

Main updates

The requirements for berthing and tug impact are aligned with IACS CSR (Common Structural Rules for Bulk Carriers and Oil tankers) 

Berthing requirements to stiffeners and primary supporting members are taken out 

Particular requirements to Tug Impact areas are taken out of the main class scope and are planned to be offered as a separate class notation

Topic

Welding

DNV-RU-SHIP

Pt.3 Ch.13

Main updates

Updated rules for tee and cross joints with a more specific list of details for partial or full penetration welding 

Simplified requirements for welding of primary support members introducing weld factors dependent on actual stress factors

Topic

Rotating machines – drivers

DNV-RU-SHIP

Pt.4 Ch.3

Main updates

Introduced engine-related requirements for fuels methanol, ethanol, LPG and ammonia

Topic

Electrical installations

DNV-RU-SHIP

Pt.4 Ch.8

Main updates

Introduced requirements for lithium-ion battery systems less than 20kWh
Topic DNV-RU-SHIP Main updates

Topic

Bulk carriers and dry cargo ships

DNV-RU-SHIP

Pt.5 Ch.1

Main updates

Clarified that the requirement for water ingress alarm is valid for ships below 80 m of length only

Topic

Oil tankers

DNV-RU-SHIP

Pt.5 Ch.5

Main updates

Opened for class notation Shore power

Topic

Chemical tankers

DNV-RU-SHIP

Pt.5 Ch.6

Main updates

Opened for class notation Shore power

Topic

Liquefied gas tankers

DNV-RU-SHIP

Pt.5 Ch.7

Main updates

Introduced alternatives to ventilations systems for CO2 transportation
Topic DNV-RU-SHIP Main updates

Topic

Electrical energy storage   

DNV-RU-SHIP

Pt.6 Ch.2 Sec.1  

Main updates

Updated rules to increase safety level

Topic

Gas fuelled - LNG

DNV-RU-SHIP

Pt.6 Ch.2 Sec.5

Main updates

Aligned with IGF code entering into force January 2024, however requirement for double wall piping on deck is not included.

Topic

Low flashpoint liquid fuels

DNV-RU-SHIP

Pt.6 Ch.2 Sec.6

Main updates

Aligned rules with IMO requirements 

Addressed the toxic aspects of methanol 

Introduced requirements for boiler arrangements fuelled by methanol

Topic

Gas fuelled - LPG

DNV-RU-SHIP

Pt.6 Ch.2 Sec.13

Main updates

Aligned with IMO draft interim guideline for the use of LPG as fuel 

Aligned with IGF code entering into force January 2024, however requirement for double wall piping on deck is not included.

Topic

Gas fuelled - ammonia

DNV-RU-SHIP

Pt.6 Ch.2 Sec.14

Main updates

Project experienced based update – introducing both decrease and increase in rule requirements

Topic

Navigation, manoeuvring and position keeping

DNV-RU-SHIP

Pt.6 Ch.3

Main updates

Introduced specific requirements for field of vision for vessels of unconventional design like WAPS and WTIV. 

Opened for replacing line of sight requirements with the use of CCTV systems

Topic

Transportation of containers

DNV-RU-SHIP

Pt.6 Ch.5 Sec.1

Main updates

Changed the requirement for wave breaker to a voluntary option

Topic

Cyber security

DNV-RU-SHIP

Pt.6 Ch.5 Sec.21

Main updates

Aligned technical content of rules with IACS UR E26 and E27

Topic

Additional safety for container vessels

DNV-RU-SHIP

Pt.6 Ch.5 Sec.23

Main updates

Reduced the discharge rate for fixed monitors

Topic

Electrical shore connections

DNV-RU-SHIP

Pt.6 Ch.7 Sec.5

Main updates

Opened for high voltage shore connection within the cargo deck area for oil and chemical tankers

Topic

Data collection infrastructure

DNV-RU-SHIP

Pt.6 Ch.11 Sec.1

Main updates

Introduced simplified D-INF notation
Additional class notations (Pt.6)

Propulsion, power generation and auxiliary systems (Ch.2)

Electrical energy storage - Battery (Sec.1)

Introducing further developed rules on: 

  • prevention of water ingress into the EES space considering collision and grounding 
  • prevention of gas spreading to other spaces and outside escape and evacuation areas
  • prevention of humid/salty air and leakages from cooling systems and ventilation ducts that may cause fault currents 
  • alternative designs, new class guideline planned for publication late 2023.

Gas fuelled LPG (Sec.13)

Aligning with IMO and IGF code on the following: 

  • machinery space shall be arranged as gas safe machinery space
  • accepting self monitoring gas detectors in place of voting principle
  • hazardous zone 2 for spaces containing fans serving hazardous area.
Gas fuelled ammonia (Sec.14)

The rule update focuses on: 

  • increase in allowable limits for normal operation emissions of ammonia to the atmosphere
  • requirements for dispersion analysis to be carried out for emergency scenarios
  • increased use of water-based safety systems in relation to ammonia leaks
  • reference to alternative design process for matters related to fire safety and life saving
  • prescriptive requirements included for enclosed bunkering stations

Equipment and design features (Ch.5)

Cyber security (Sec.21)

  • general alignment with IACS UR E26 and E27
  • class notation Cyber secure(Essential) is kept as voluntary for new vessels contracted on or after 2024-01-01
  • cyber security capabilities are subject to product certification before delivery of systems to shipyard
  • clarification of benefits gained by type approved cyber security capabilities
  • added systems to default system under consideration (SuC), serving vessel functions anchoring, lighting and pollution prevention
  • added secure product development lifecycle requirements to manufacturer.

 

 

Oslo, Norway, 2023-06-25
Henning B. Karlsen
Service Responsible – Ship Class