Leading the way: dedicated to safety and clean seas, IACS members make a unique contribution to maritime safety and regulation through technical support, compliance verification and research and development. More than 90% of the world's cargo carrying tonnage is covered by the classification design, construction and through-life compliance rules and standards set by the ten Member Societies and one Associate of IACS.



Clasification societies today

Why is it called classification?

The International Association of Classification Societies - IACS

IACS Code of Ethics


Appendix 1 – the language of classification and surveys

Classification notations

Assignment, maintenance, suspension and withdrawal of class

Surveys - an overview of requirements and certification

- Definitions and procedures related to classification surveys

- Definitions and procedures related to statutory surveys

Appendix 2

The members of IACS

© IACS 2006


photos: surveyors

Corr Aug 2005, Jan 2006



subject to the terms and conditions shown on the IACS website www.iacs.org.uk. © ABS, others © Colin Wright



Classification societies today

Classification societies are organizations that establish and apply technical standards inrelation to the design, construction and survey of marine related facilities including ships and offshore structures.

The vast majority of ships are built and surveyed to the standards laid down by classification societies.

These standards are issued by the classification society as published rules. A vessel that hasbeen designed and built to the appropriate rules of a society may apply for a certificate ofclassification from that society. The society issues this certificate upon completion of relevant classification surveys.

Such a certificate does not imply, and should not be construed as an express warranty ofsafety, fitness for purpose or seaworthiness of the ship. It is an attestation only that the vesselis in compliance with the standards that have been developed and published by the society issuing the classification certificate.

More than 50 organizations worldwide define their activities as providing marine classification.Ten of those organizations form the International Association of Classification Societies(IACS). It is estimated that these ten societies, together with the additional society that has been accorded associate status by IACS, collectively class about 94 percent of all commercial tonnage involved in international trade worldwide. A listing of the IACS member societies, and the associate, is provided in appendix 2.

Classification is one element within a network of maritime safety partners. Other elements are parties such as the shipowner, the shipbuilder, the flag State, port States, underwriters, shipping financiers, and charterers among others.

The role of classification and classification societies has been recognized in the International Convention for the Safety of Life at Sea, (SOLAS) and in the 1988 Protocol to the International Convention on Load Lines. This statutory role is addressed later in this note.

As an independent, self-regulating, externally audited, body, a classification society has no commercial interests related to ship design, ship building, ship ownership, ship operation, ship management, ship maintenance or repairs, insurance, or chartering. In establishing its rules, each classification society may draw upon the advice and review of members of the industry who are considered expert in their field.

Classification rules are developed to assess the structural strength and integrity of essential parts of the ship’s hull and its appendages, and the reliability and the function of the propulsion and steering systems, power generation and those other features and auxiliary systems which have been built into the ship in order to maintain essential services on board. Classification rules are not intended as a design code and in fact cannot be used as such.

A ship built in accordance with an IACS Member's rules will be assigned a class designation by the society on satisfactory completion of the relevant surveys. For ships in service, the society carries out surveys to ascertain that the ship remains in compliance with those rules. Should any defects that may affect class become apparent, or damages be sustained between the relevant surveys, the ship owner and operator are required to inform the society concernedwithout delay.



A ship is maintained in class provided that the relevant rules have, in the opinion of the society concerned, been complied with and surveys carried out in accordance with its rules.

Classification societies also maintain significant research departments that contribute towards the on-going development of appropriate, advanced technical standards.

Why is it called classification?

In the second half of the 18th century, marine insurers, based at Lloyd's coffey house in London, developed a system for the independent inspection of the hull and equipment of ships presented to them for insurance cover. In 1760 a Committee was formed for this express purpose, the earliest existing result of their initiative being Lloyd's Register Book for the years 1764-65-66.

At that time, an attempt was made to 'classify' the condition of each ship on an annual basis. The condition of the hull was classified A, E, I, O or U, according to the excellence of its construction and its adjudged continuing soundness (or otherwise). Equipment was G, M, or B: simply, good, middling or bad. In time, G, M and B were replaced by 1, 2 or 3, which is the origin of the well-known expression 'A1', meaning 'first or highest class'.

The concept of classification caught on around the world. Bureau Veritas (BV) was founded in Antwerp in 1828, moving to Paris in 1832. 'Lloyd's Register of British and Foreign Shipping' was reconstituted as a self-standing 'classification society' in 1834; rules for construction and survey were published the same year.

Registro Italiano Navale (RINA) dates from 1861; American Bureau of Shipping (ABS) traces its origins back to 1862. Adoption of common rules for ship construction by Norwegianinsurance societies in the late 1850s led to the establishment of Det Norske Veritas (DNV) in 1864. Germanischer Lloyd (GL) was formed in 1867 and Nippon Kaiji Kyokai (ClassNK) in 1899. The Russian Maritime Register of Shipping (RS) was an early offshoot of the River Register of 1913. More recent foundations have beenYugoslav Register of Shipping (now the Croatian Register of Shipping (CRS)) in 1949, China Classification Society (CCS), 1956; Korean Register (KR), 1960; and Indian Register of Shipping (IRS), 1975.

As the classification profession evolved, the practice of assigning different classifications has been superseded, with some exceptions. Today a ship either meets the relevant classsociety’s rules or it does not. As a consequence it is either 'in' or 'out' of 'class'. However, each of the classification societies has developed a series of notations that may be granted to a vessel to indicate that it is in compliance with some additional criteria that may be either specific to that vessel type or that are in excess of the standard classification requirements.

The International Association of Classification Societies - IACS

IACS can trace its origins back to the International Load Line Convention of 1930 and its recommendations. The Convention recommended collaboration between classificationsocieties to secure " strength upon which freeboard is based…

Following the Convention, RINA hosted the first conference of major societies in 1939 - also attended by ABS, BV, DNV, GL, LR and NK - which agreed on further cooperation between the societies.

A second major class society conference, held in 1955, led to the creation of Working Parties on specific topics and, in 1968, to the formation of IACS by seven leading societies. The value of their combined and unique level of technical knowledge and experience was quickly recognised. In 1969, IACS was given consultative status with IMO. It remains the only nongovernmental organization with Observer status which is able to develop and apply rules.



Compliance with the IACS Quality System Certification Scheme (QSCS) and observance of the IACS Code of Ethics is mandatory for both IACS Member and Associate status.

IACS is governed by a Council, with each Member represented by a high management figure. Under the Council is the General Policy Group (GPG), made up of a senior management figure from each Member, which develops and implements actions giving effect to the policies, directions and long term plans of Council. The chair of GPG is taken by the Member holding the Council chair.

IACS Code of Ethics

The Code of Ethics is the bedrock of the IACS members’ work and can be found on the IACS website www.iacs.org.uk .

It states, inter alia:

"Classification Societies live on their reputation. Acceptance of their technical work can only be maintained by continuously proving integrity and competence.”  and

"Competition between Societies shall be on the basis of services (technical and field) rendered to the marine industry but must not lead to compromises on safety of life and property at sea or to the lowering of technical standards."



Scope of classification

Implementing the published rules, the classification process consists of:

A technical review of the design plans and related documents for a new vessel to verify compliance with the applicable rules;

Attendance at the construction of the vessel in the shipyard by a classification society surveyor(s), and at the relevant production facilities that provide key components such as the steel, engine, generators and castings, to verify that the vessel is constructed in accordance with the classification rules;

Upon satisfactory completion of the above, the shipowner’s request for the issuance of a class certificate will be considered by the relevant classification society and, if deemed satisfactory, the assignment of class will be approved and a certificate of classification issued;

Once in service, the owner must submit the vessel to a clearly specified program of periodical class surveys, carried out onboard the vessel, to verify that the ship continues to meet the relevant rule conditions for continuation of class.

Class rules do not cover every piece of structure or item of equipment on board a vessel, nor do they cover operational elements. Activities which generally fall outside the scope of classification include such items as: design and manufacturing processes; choice of type and



power of machinery and certain equipment (e.g. winches); number and qualification of crew or operating personnel; form and cargo carrying capacity of the ship and manoeuvring performance; hull vibrations; spare parts; life-saving appliances and maintenance equipment. These matters may however be given consideration for classification according to the type of ship or class notation(s) assigned.

It should be emphasized that it is the shipowner who has total control over a vessel, including the manner in which it is operated and maintained. Classification is voluntary and its effectiveness depends upon the shipowner, and other interests, operating in good faith by disclosing to the class society any damage or deterioration that may affect the vessel’s classification status. If there is the least question, the owner should notify class and schedule a survey to determine if the vessel is in compliance with the relevant class standard.

A class surveyor may only go on board a vessel once in a twelve-month period. At that time it is neither possible, nor expected that the surveyor scrutinize the entire structure of the vessel or its machinery. The survey involves a sampling, for which guidelines exist based upon empirical experience which may indicate those parts of the vessel or its machinery that may be subject to corrosion, or are exposed to the highest incidence of stress, or may be likely to exhibit signs of fatigue or damage.

Assignment, maintenance, suspension and withdrawal of class

Class is assigned to a ship upon the completion of satisfactory surveys, undertaken in order to check compliance with the rules of the society, at the time of newbuilding. Specific procedures apply when an existing ship is transferring from one class society to another.

Classed ships are subject to surveys to continue in class. These surveys include the class renewal (also called “special survey”), intermediate survey, annual survey, and bottom/docking surveys of the hull. They also include tailshaft survey, boiler survey, machinery surveys and, where applicable, surveys of items associated with the maintenance of additional class notations.

The surveys are to be carried out in accordance with the relevant class requirements in order to confirm that the condition of the hull, machinery, equipment and appliances is in compliance with the applicable rules.

The classification of a ship is based on the understanding that the ship is loaded, operated and maintained in a proper manner by competent and qualified crew or operating personnel. It is the owner's responsibility to ensure proper maintenance of the ship until the next survey required by the rules. It is the duty of the owner, or its representative, to inform the surveyor, on boarding the ship, of any events or circumstances affecting the class.

Where the conditions for the maintenance of class are not complied with, class will be suspended, withdrawn or revised to a different notation, as deemed appropriate by the society when it becomes aware of the condition. The ship may lose its class either temporarily or permanently. In the former case it is referred to as “suspension” of class; in the latter case as “withdrawal” of class. In the case of surveys that are not carried out within the specified time frame, or if the vessel is operated in a manner that is outside its classification designation, the suspension may be automatic.

Classification surveys

A classification survey is a visual examination that normally consists of:

detailed checks of selected parts, witnessing tests, measurements and trials where applicable.

The United Nations Convention on the Law of the Sea (UNCLOS) is an umbrella convention

concerned with many aspects of the sea and its uses, including the granting of registration of a

ship by a State. Once a ship is registered, the flag State has certain duties laid out in

UNCLOS. In particular, under Article 94, the flag State must

jurisdiction and control in administrative, technical and social matters over ships flying its flag”


and take



“effectively exercise its “such measures for ships flying its flag as are necessary to ensure safety at sea…..”


International Conventions have been agreed, setting out uniform standards to facilitate

acceptance of a ship registered in one country in the waters and ports of another and in the

general furtherance of safety at sea and protection of the environment. These standards are

commonly referred to as ‘statutory’ requirements. Broadly, they cover three distinct areas:

1) Aspects of the ship’s design and its structural integrity – load line and stability in the intact

and damaged condition, essential propulsion, steering equipment, etc.;

2) Accident prevention, including navigational aids and pollution and fire prevention;

3) The situation after an accident (fire, flooding) including containment and escape.

Some or all of these may also be reproduced in a particular class society’s rules.

SOLAS Ch II-1, Reg 3-1 states that, in addition to the requirements of the other (SOLAS)

regulations, ships shall be designed, constructed and maintained in compliance with the

structural, mechanical and electrical requirements of a classification society which is

recognised by the Administration in accordance with the provisions of regulation XI/1 (see

below), or with applicable national standards of the Administration which provide an equivalent

level of safety.

Where the classification survey result is taken as evidence of compliance with the

corresponding statutory requirement, e.g. load line or safety construction (hull, machinery,

boilers, electrical equipment, etc.), this survey is de facto given the status of a statutory survey

on behalf of the flag Administration, if the society is acting as its recognised organization in

this respect.

When a ship is suspended or withdrawn from class, IACS members notify the flag

Administration concerned and publish the information e.g. on its website. As a consequence,

the flag Administration generally invalidates the statutory certificates concerning construction

and equipment.

Recognised Organizations

SOLAS and the other International Conventions permit the flag Administration to delegate the

inspection and survey of ships to a Recognised Organization (RO). The organization is

empowered to require repairs or other corrective action to a ship and in most cases, to

withdraw or invalidate the relevant certificate if the necessary action is not taken (e.g. SOLAS

Chapter I, Reg 6).

IMO Resolution A 739(18) lays down

minimum standards for ROs. Fundamentally

it requires the organization to demonstrate its

technical competence and to be governed by

the principles of ethical behaviour. The RO

should be subject to the certification of its

quality system by an independent body of

auditors accepted by the Administration.

Together with IMO Resolution A.789(19), which presents specifications on the survey and

certification functions of ROs, these resolutions provide the criteria and framework to which a

flag must be satisfied that their RO’s meet. IACS Members have been found to meet

resolutions A.739(18) and A.789(19) by all of the Administrations (approximately 100) that are

Parties to SOLAS.

The RO is responsible and accountable to the flag Administration for the work that it carries

out on its behalf. The principles of the inspection and survey work are the same as in respect



of classification surveys, that is, the verification by the RO that a ship is in compliance with

applicable requirements at the time of the survey. The scope of these inspections and surveys

regarding safety and pollution prevention are laid down by the relevant international

conventions to which the Government is a signatory, together with additional instructions that

may be issued by the flag Administration.

The statutory regulations build on the classification foundation. Classification rules are a vital

part of the statutory legislation. A holistic approach to the constructional safety of the ship

benefits from one organization verifying compliance with both statutory and class

requirements. A key lesson from other regulated industries is that inspection/verification

should be undertaken by as few parties as possible - reducing unnecessary interfaces which

could lead to breakdowns in the system.

Thus, as a matter of policy IACS members do not undertake ‘statutory’ work on ships that they

do not themselves class. The significant exception to this policy is ISM and International Ship

and Port Facility Security (ISPS) Code certification where it may be efficient for a Company to

implement a common Safety Management System (SMS) or Ship Security Plan (SSP) on a

fleet basis as that fleet may be classed by more than one society. However, systems are in

place for the classing society to inform the owner, the ISM certifying society and/or the flag

Administration in cases where there is serious reason to doubt the continuing effectiveness of

the SMS (IACS Procedural Requirement 17 - Routine and Ad Hoc Reporting by Surveyors of

Evidence of Possible Safety Management System Failures). A similar approach is being

taken in respect of ISPS certification.

Development of Rules and Regulations

Historical development

Classification rules have been developed over many years by each society through extensive

research and development and service experience. In addition, certain Unified Requirements

have been agreed by IACS members and transposed into the individual members’ rules.

As mentioned above, ‘statutory’ requirements have been developed at IMO and where

necessary, Unified Interpretations of them are adopted by IACS.

A note on Unified Requirements, Unified Interpretations and other IACS resolutions is given


Future development

There is always room for improvement in the way rules and regulations are developed and

framed. It is anticipated that the IMO will set the top-level goals and levels of risk regarding

safety and environmental protection and the class societies enact rules to achieve these

goals, within their sphere of activity.

Present class rules do, of course, have goals built in, but these are not always transparent.

The aim is to develop a new and transparent regulatory framework, initially focused on hull

structures and representing a significant change to the current complex system of statutory

international and national regulations, classification rules and industry standards.



The basic principle is to establish clear,

demonstrable and verifiable goals to the

effect that a properly built, operated and

maintained ship remains safe and

environmentally friendly for its whole life.

This goal-based standards approach aims at

moving the regulatory framework from a

culture of compliance, governed by

prescriptive rules, to a culture of

benchmarking, backed by functional riskbased

requirements. It will move from given

prescriptive solutions to goals that can be

achieved by alternative designs at an

equivalent level of safety, promoting

technology innovations within the shipping


Once the framework for goal-based standards is set at the IMO, it will be the role of IACS, as

technical experts, to provide the rules to support these goals, and these rules will be

"common" to all IACS societies.

Common Rules for hull structures of oil tankers and bulk carriers were adopted in December

2005 for implementation on 1 April 2006. This was a most ambitious and expensive project

and one of the most important single steps in the development of maritime rules that IACS has

ever been involved with. The new Rules can be downloaded from the IACS website.

IACS resolutions


In addition to the common rules projects, IACS resolutions on technical or procedural matters

may be developed, generally through specialist working groups overseen by the General

Policy Group (GPG).

The principal categories of resolution are listed below and may be found on the IACS website,

and in the so-called “Blue Book” CD-ROM:

Unified Requirements

Unified Requirements (UR) are resolutions on matters directly connected to or covered by

specific rule requirements and practices of classification societies and the general philosophy

on which the rules and practices of classification societies are established.

Subject to ratification by the governing body of each Member Society and Associate, URs are

to be incorporated in the rules and practices of the Member Societies and the Associates,

within one year of approval by the IACS Council. The existence of a UR does not oblige a

Member Society or an Associate to issue respective rules if it chooses not to have rules for

the type of ship or marine structure concerned.

URs set forth minimum requirements. Each Member and Associate remains free to set more

stringent requirements.



Unified Interpretations

Unified Interpretations (UI) are resolutions on matters arising from implementing the

requirements of IMO Conventions or Recommendations. They provide uniform interpretations

of Convention Regulations or IMO Resolutions on those matters which in the Convention are

left to the satisfaction of the Administration or where more accurate wording has been found


Interpretations are circulated to Administrations through submission to IMO for consideration,

as appropriate.

Interpretations are to be applied by Member Societies and Associates, under the authority of

the flag Administrations, to the ships registered by those flag Administrations which have not

issued definite instructions on the interpretation of the Regulations concerned. A date for

implementation by IACS Members is established for each UI, unless the Administration has

issued instructions to the contrary.


Recommendations (Rec) are resolutions, not necessarily matters of class, on which IACS

considers advice would be beneficial to the industry.

Procedural Requirements

Procedural Requirements (PR) are mandatory resolutions on matters of procedures to be

followed by Members and Associates.


Qualities and qualifications

A memorandum of 1834 has not been


“The utmost care and discrimination have

been exercised by the Committee in the

selection of men of talent, integrity, and

firmness as Surveyors, on whom the practical

efficacy of the system and the contemplated

advantages must so materially depend; the

Committee have in their judgement appointed

those persons only…who appeared to them

to be most competent to discharge the

important duties of their situations with fidelity

and ability, and to ensure strict and impartial

justice to all parties whose property shall

come under their supervision.”

Today, the training, qualification and

monitoring of surveyors and auditors is

governed by IACS Procedural Requirements,

with the same aim in mind.



Appendix 1 – the language of classification and surveys

Classification notations

Classification notations are indicative of the specific rule requirements which have been met.

Depending on the classification society, the classification notations are assigned to the ship

according to ship type, service, navigation and/or other criteria which have been provided by

the owner and/or builder, when requesting classification.

Classification notations assigned to a ship are indicated on the certificate of classification as

well as in the Register of Ships published by the society. These notations can be generalized

by the following types which may be used in combination:







Class symbol

main class symbol construction marks service notations with additional service features, as applicable navigation notations geographic notations additional class notations

The main class symbol expresses the degree of compliance of the ship with specific rule

requirements regarding its construction.

Construction mark

The construction mark, when assigned, identifies the procedure under which the ship and its

main equipment or arrangements have been surveyed for initial assignment of the class.

Service notations

The service notations, when assigned, define the type and/or service of the ship which has

been considered for its classification.

A ship may be assigned several different service notations. In such case, the specific rule

requirements applicable to each service notation will have been complied with.

Navigation and operating area notations

Navigation notations

Some classification societies define limiting areas for navigation (e.g. high seas, coastal

waters, and sheltered waters), and/or limiting environmental conditions for certain types of

ships and marine structures.

The assignment of restricted navigation notations may include the reduction of scantlings or

specific arrangements.

The assignment of a navigation notation by classification societies does not dispense the

owner from compliance with any applicable international and/or national regulations

established by the Administrations for ships operating in national waters, or a specific area, or

a navigation zone.



Operating or service area notations

The operating area notation specifies the service area where the ship (e.g. dredgers, crane

pontoons, port tugs) can operate as regards its assigned class.

Additional class notations

When assigned, an additional class notation gives details of additional equipment or specific

arrangements, which have been specially requested by the owner.

Assignment, maintenance, suspension and withdrawal of class

Assignment of class

Class is assigned to a ship upon the completion of satisfactory surveys, held in order to check

compliance with the rules of the society



developed by the IACS Member Societies for ships transferring class between

members, or


society, or not classed at all.


Maintenance of class

. This assignment may be given in the following cases: On completion of the new building, after satisfactory surveys have been performed, a satisfactory survey of an existing ship carried out in accordance with the agreement a satisfactory specific class survey of an existing ship not classed with an IACS

Classed ships are subject to surveys for maintenance of class. These surveys include the

class renewal (also called “special survey”), intermediate, annual, and bottom/docking surveys

(either a survey in dry dock or an in-water survey) of the hull, tailshaft survey, boiler survey,

machinery surveys and surveys for the maintenance of additional class notations, where

applicable. Such surveys are carried out at the intervals and under the conditions given below.

The surveys are to be carried out in accordance

with the relevant requirements in order to confirm

that the condition of the hull, machinery,

equipment and appliances comply with the

applicable rules. It is owner’s duty to ensure that

the ship’s maintenance is kept at a satisfactory

level in order to maintain the condition between


The extent of any survey depends upon the

condition of the ship and its equipment. In

addition to the minimum required extent of surveys

specified in the rules, should the surveyor have a

doubt as to the lack of maintenance or condition of

the ship or its equipment, or be informed by the

owner of any deficiency or damage which may

affect class, further examination and testing may

be conducted as considered necessary.

Suspension of class

The class may be suspended following a decision made by the society when one or more of

the following occurs:



when a ship is not operated in compliance with the rule requirements,



affecting the class,


requesting the attendance of a surveyor.

In addition, class is automatically suspended:


within the time granted in special circumstances for the completion of the survey,

unless the ship is under attendance by the society’s surveyor(s) with a view to

completion prior to resuming trading;


corresponding survey time windows.

Suspension of class with respect to the above cases will remain in effect until such time as the

due surveys and any other survey deemed appropriate by the society have been completed.

In addition to the circumstances for which automatic suspension may apply, the class of a ship

will be subject to suspension procedures following a decision of the society:


specified, unless it is postponed before the due date by agreement with the society


stipulated by the society also taking into account any extensions granted


entitled to retain its class even on a temporary basis (pending necessary repairs or

renewals, etc.)


accordance with a special requirement.

In all cases suspension will remain in effect until such time as matters are rectified and the

class is reinstated or class is withdrawn.

Depending on the society’s procedures, the suspensions of class which are not automatic may

take effect either when they are decided by the society or from the date when the conditions

for suspension occurred. However once the conditions for class suspension/withdrawal are

met and before any decision by the society can be taken, either because the society is not

aware of the circumstances (surveys dates, etc. are recorded but not systematically

monitored) or because the decision is not yet taken, maintenance of class cannot generally be

confirmed by the society during this period.


Withdrawal of class

when a ship proceeds to sea with less freeboard than that assigned, when the owner fails to request a survey after having detected defects or damages when repairs, alterations or conversions affecting the class are carried out without when the class renewal/special survey has not been completed by its due date or when the annual or intermediate surveys have not been completed by the end of the when a recommendation/condition of class is not dealt with within the time limit when one or more other surveys are not held by their due dates - or the dates when, due to the nature of reported defects, the society considers that a ship is not in other circumstances where the owner fails to submit the ship to a survey in

The society will withdraw the class of a ship when:



intentions to repair the ship for re-instatement of class,



Withdrawal of class takes effect from the date on which the circumstances causing such

withdrawal occur or when it is decided.



requested by the owner, the class has been suspended for more than six months, the ship is reported as a constructive total loss and the owner does not give his the ship is reported lost the ship will not trade further as declared by its owner.


Notification of suspension or withdrawal

When class is suspended or withdrawn, the society will at the same time:




Surveys – an overview of requirements and certification

inform the owner, flag Administration and underwriters (the latter at their request) delete the ship from the Register of Ships convey the information to appropriate databases (Equasis, SIReNaC, etc.)

Definitions and procedures related to classification surveys

Period of certificate of class

The period of the certificate of class starts either from the date of initial classification, or from

the credited date of the last class renewal/special survey, and expires at the due date

assigned for the next class renewal/special survey.

Note: The due date is the end of the time window for that survey.

Anniversary date

The anniversary date is the day and the month given in the certificate of class which

corresponds to the expiry date of the certificate.

Survey time window

The survey time window is the fixed period during which the annual and intermediate surveys

are to be carried out.

Overdue surveys

Each periodical survey is assigned a due date specified by the relevant rules by which it is to

be completed.

A survey becomes overdue when it has not been completed by its due date. For example:

Anniversary date: 15th April

The annual survey can be validly carried out from 16th January to 15th July. If not

completed by 15th July, the annual survey becomes overdue and class will be suspended


Recommendations/Conditions of Class

‘Recommendation’ and ‘Condition of Class’ are different terms used by IACS societies for the

same thing and are those requirements imposed by the society which will affect the class if not

complied with by the assigned due date.


Other information of assistance to the surveyor and owners may be recorded as ‘memoranda’

or a similar term. They may, for example, include notes concerning materials, barred engine

speed ranges and other constructional information. A memorandum may also define a

structural condition which, though deviating from the technical standard, does not affect the

class (e.g. slight indents in the shell, which do not have an effect upon the overall strength of

the hull, or minor deficiencies, which do not affect the operational safety of the machinery).



In addition, memoranda could define recurring survey requirements, such as annual survey of

specified spaces, or retrofit requirements, which have the de-facto effect of conditions of class.

Specific questions in relation to the meaning of memoranda / recommendations / conditions of

class are to be addressed to the classification society concerned though the owner of the ship.

Periodical surveys, periodicity and scope

Class renewal survey / special survey

Class renewal surveys/special surveys are carried out at five-year intervals. However,

consideration may be given by the society, in exceptional circumstances, to granting an

extension for a maximum period of three months after the due date. In such cases the next

period of class will start from the due date for the previous class renewal survey before the

extension was granted.

The special survey may be commenced at the 4th annual survey and be progressed with a

view to completion by the 5th anniversary date.

The class renewal surveys/special surveys include extensive examinations to check that the

structures, main and essential auxiliary machinery, systems and equipment of the ship remain

in a condition which satisfies the rules. The examinations of the hull are generally

supplemented by thickness measurements and witnessing of tests as specified in the rules

and as deemed necessary by the attending surveyor to assess that the structural integrity

remains effective and to help discovering substantial corrosion, significant deformation,

fractures, damages or other structural deterioration.

Annual survey

Annual surveys are to be carried out within a window from three months before to three

months after each anniversary date.

At the time of annual surveys, the ship is generally examined. The survey includes an

inspection of the hull, equipment and machinery of the ship and some witnessing of tests

thereof, so far as is necessary and practical in order to check that the ship remains in a

general condition which satisfies the rule requirements.

Intermediate survey

An intermediate survey is to be carried out within the window from three months before the

second to three months after the third anniversary date.

The intermediate survey includes examinations and checks as specified in the rules on the

structure to show that the ship is in a satisfactory condition.

According to the type and age of the ship the examinations of the hull are supplemented by

thickness measurements as specified in the rules and where deemed necessary by the

attending surveyor.

Bottom / Docking survey

A bottom/docking survey is the examination of the outside of the ship's hull and related items.



This examination may be carried out with the

ship either in dry dock (or on a slipway) or afloat:

in the former case the survey will be referred to

as dry-docking survey, while in the latter case as

in-water survey. The conditions for acceptance of

an in-water survey in lieu of a dry-docking survey

will depend on the type and age of the ship and

the previous history.

The outside of the ship's hull and related items

are to be examined on two occasions in the fiveyear

period of the certificate of class with a

maximum of 36 months between surveys.

One of the two bottom/docking surveys to be performed in the five-year period is to be

concurrent with the class renewal/special survey and this bottom/docking survey is to be a drydocking


For ships subject to the Enhanced Survey Programme (ESP) and 15 years of age and above,

the intermediate bottom/docking survey is to be carried out in a dry-dock.

Tailshaft survey

A tailshaft survey is the survey of screwshafts and tube shafts (hereafter referred to as

tailshafts) and the stern bearing.

The different types of surveys to which tailshafts may be subjected and the intervals are:




Tailshaft complete survey

complete survey modified survey partial survey

Tailshafts are to be submitted to complete examination at a periodicity based on the type of

shaft and its design. “Complete” means that the shaft is drawn up for examination or that other

equivalent means of examination are provided.

Tailshaft modified survey

A modified survey of the tailshaft is an examination which may be accepted at alternate fiveyearly

surveys for tailshafts provided that the shaft arrangement is in accordance with specific


Partial survey

A partial survey allows a postponement of the complete survey, having a periodicity of 5 years,

for 2.5 years

Boiler surveys

Boilers and thermal oil heaters are to be surveyed twice in every five-year period. The

periodicity of the boiler survey is normally 2.5 years.

Steam boilers, superheaters and economisers are examined internally and externally. To this

end, boilers are to be drained and suitably prepared for the examination of the water-steam



side and the fire side. Where necessary, the external surfaces are to be made accessible for

inspection by removal of insulation and lining.

Upon completion of the internal survey, the boiler is examined under steam and fuel oil

burners and safety devices checked under working conditions.

The setting pressures of safety valves are to be checked. For auxiliary exhaust gas boilers, if

steam cannot be raised in port, the Chief Engineer is to set the safety valves at sea and record

the setting pressures in the log-book.

Non-periodical surveys

Such surveys are carried out for example:



conversion, postponement of surveys or recommendations/conditions of class;


In the event of damage which affects

or may affect the class of the ship, the

owner is to advise the society without


Arrangements are then made at the

earliest opportunity for a surveyor to

attend and ascertain the extent of the

damage and foreseen repairs.

Any damage in association with wastage over the allowable limits (including buckling,

grooving, detachment or fracture), or extensive areas of wastage over the allowable limits,

which affects or, in the opinion of the surveyor, will affect the vessel’s structural, watertight or

weathertight integrity, is to be promptly and thoroughly repaired thereby removing the need for

the imposition of any associated condition of classification. Otherwise, damages and partial or

temporary repairs considered acceptable by the surveyor for a limited period of time are

covered by an appropriate recommendation/condition of class.

Damages or repairs required by the surveyor to be re-examined after a certain period of time

are also covered by an appropriate recommendation/condition of class.


Class certificate

Issue of the certificate of classification

to update classification documents (e.g. change of owner, name of the ship, change of to deal with damage or suspected damage, repair or renewal work, alterations or At the time of port State control inspections

A certificate of classification, bearing the class notations assigned to the ship and an expiry

date, is issued to all classed ships. This certificate may also be provided with annexes

supplying information sufficient for the management of the certificate, for determining the class

surveys date and for immediate assessment of possible irregularities (overdue

recommendations, etc.).

An interim/provisional certificate of classification may serve as a certificate of classification in

certain situations when deemed necessary by the society.



Validity of the certificate of classification

A certificate of classification, properly endorsed, is valid until the expiry date unless advised

otherwise by the society or there are no grounds for suspension or withdrawal of class.

Endorsement of certificate of classification

When annual and intermediate surveys are satisfactorily completed, the certificate of

classification is:


entries in the appropriate annexes attached to the certificate concerning the

recommendations/conditions of class, if any, and/or the surveys held


Where applicable, memoranda are also endorsed in the appropriate annex.

endorsed for the periodical surveys; according to the practice of some societies, endorsed accordingly, with the relevant.

Definitions and procedures related to statutory surveys


The conventions require an initial survey before a vessel is put in service for the first time and

then receives its first certificate, and a certificate renewal survey at one, two or five year

intervals thereafter, depending on the certificate and type of ship. In addition, for those

certificates valid for more than one year, surveys at annual intervals are required, one of

which, at approximately half way and termed ‘intermediate’, may be of greater extent than an

ordinary ‘annual’. The ‘Harmonised System of Survey and Certification’ (HSSC) implemented

by many Administrations under IMO resolutions A.746(18) and A.882(21), brings all SOLAS

(except for passenger ships), MARPOL and Load Line convention surveys into a five-year

cycle. With respect of safety equipment surveys, HSSC uses the term ‘periodical’ instead of

‘intermediate’, and for radio, ‘periodical’ instead of ‘annual’. These latter take the place of the

renewal surveys held under the shorter certificate renewal cycles.

The scope of survey can generally be

harmonized with the extents of the

classification surveys detailed above and, as

far as possible, are held concurrently with


The scope of survey, which does not

necessarily encompass 100% of the

structure, equipment, etc of the ship, is laid

down by IMO resolutions and generally

increases with age. It is to include

sufficiently extensive examinations and

checks to show that the structures, main and

essential auxiliary machinery, systems and

equipment of the ship are in a satisfactory

condition and are fit for the service for which

the ship is intended insofar as the

requirements concerned are met.

Between surveys, the conventions require the flag Administration to make it compulsory for

the owner to maintain the ship to conform to the regulations to ensure that the ship will in all

respects remain fit to proceed to sea without danger to the ship or persons on board or

unreasonable threat of harm to the marine environment.



Initial survey

An initial survey is an inspection of the design and construction of the relevant structure,

machinery and equipment of the ship to ensure that it complies with the requirements of the

regulations and is fit for the service for which the ship is intended.

Renewal survey

A renewal survey is an inspection of the structure, machinery and/or equipment, as applicable,

to ensure that their condition remains in compliance with the requirements of the regulations.

Modifications to the ship having a bearing on the conformity of the vessel to the requirements

are to be declared by the owner and inspected.

Annual survey

An annual survey, in principle, includes a general inspection of the relevant structure and

equipment of the ship to confirm that it has been maintained in accordance with the

regulations and remains satisfactory for the service for which it is intended.

Intermediate survey

An intermediate survey is an inspection of specified items relevant to the particular certificate

to confirm that they are in satisfactory condition and fit for the service for which the ship is

intended. Depending on the certificate concerned and the age of the ship, the scope may

range from that of an annual survey to the equivalent of a renewal.

Periodical survey

Periodical surveys generally take the place of renewal surveys for those certificates which

previously were renewed after one or two years. However, in the case of a Load Line

Certificate which is issued on behalf of, or by, Parties that have not implemented the

harmonised system of survey and certification, the five-year renewal survey may be referred to

as the ‘periodical’ survey.

Issue of statutory certificates


Statutory certificates are issued by the RO in accordance with the terms of its recognition by

the flag Administration. Variation of the delegation of statutory authority or certificates that can

be issued by the RO exists between Administrations. The Administration should be contacted

for specific details of the authorization.

Issue, endorsement and withdrawal

A certificate is issued or endorsed after the relevant surveys are passed. A certificate may be

issued, valid for a short time period, listing corrective action to be rectified for minor

deficiencies which do not prevent the issuance of a certificate to the ship.

For most conventions, the Administration empowers the RO to withdraw or invalidate a

certificate if the required corrective action is not taken.




Appendix 2

The members of IACS are:


ABS American Bureau of Shipping

BV Bureau Veritas

CCS China Classification Society

DNV Det Norske Veritas

GL Germanischer Lloyd

KR Korean Register of Shipping

LR Lloyd's Register

NK Nippon Kaiji Kyokai (ClassNK)

RINA Registro Italiano Navale

RS Russian Maritime Register of Shipping


IRS Indian Register of Shipping

(Associate status is being phased out: Croatian Register of Shipping was an Associate until 31

December 2004)







When a surveyor identifies corrosion, structural defects or damage to hull, machinery and/or any piece of its equipment which, based on the society’s rules and in the opinion of the surveyor, affects the ship’s class, remedial measures and/or appropriate recommendations/conditions of class are specified in order to retain class.

‘Recommendation’ and ‘condition of class’ are synonymous terms used by IACS societies for requirements that specific measures, repairs, request for surveys etc., are to be carried out by the owner within a specified time period in order to retain class.

Each classed vessel is subject to a specified program of periodic surveys after delivery. These

are based on a five-year cycle and consist of annual surveys, an intermediate survey and a

class renewal/special survey (held every 5 years). The rigor of each specified survey

increases with the age of the vessel.

The class renewal surveys/special surveys include extensive in-water and out-of-water

examinations to verify that the structure, main and essential auxiliary machinery, systems and

equipment of the ship remain in a condition which satisfies the rules. The examination of the

hull is supplemented, when specified, by ultrasonic thickness measurements and the

witnessing of tests as specified in the rules and as deemed necessary by the attending

surveyor. The survey is intended to assess whether the structural integrity remains effective

and to identify areas that exhibit substantial corrosion, significant deformation, fractures,

damages or other structural deterioration.

Depending upon the age, size, type and condition of the vessel, the renewal/special survey

may take several weeks to complete.

The intermediate survey (held approximately half

way between special surveys) includes examinations

and checks as specified in the rules to determine

whether the ship remains in a general condition

which satisfies the rule requirements. According to

the type and age of the ship, drydocking may be

required and the examinations of the hull may be

supplemented by ultrasonic thickness

measurements as specified in the rules and where

deemed necessary by the attending surveyor.

At the time of annual surveys, the ship is generally examined. The survey includes an

external, general inspection of the hull, equipment and machinery of the ship and some

witnessing of tests, so far as is necessary and practical in order to determine whether the ship

remains in a general condition which satisfies the rule requirements. Older ships of certain

types may also be subject to a general examination of some specified internal areas of the

hull. Depending upon the age, size, type and condition of the vessel, an annual survey may

take from several hours to a few days to complete.


Statutory certification of ships




Leading the way: dedicated to safe ships and clean seas, IACS members make a

unique contribution to maritime safety and regulation through technical support,

compliance verification and research and development. More than 90% of the world's

cargo carrying tonnage is covered by the classification design, construction and

through-life compliance rules and standards set by the ten Member Societies and one

Associate of IACS.










Classification societies today

Why is it called classification?

The International Association of Classification Societies - IACS

IACS Code of Ethics



Scope of classification

Assignment, maintenance, suspension and withdrawal of class

Classification surveys


Statutory certification of ships



Recognised Organizations


Development of Rules and Regulations


Historical development

Future development

IACS resolutions





an overall examination of the items for survey,

Qualities and qualifications