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AIS References

U.S. Coast Guard AIS: Encoding Guide, Inspection Checklist, and Safety Alerts regarding AIS.
International Maritime Organization

The International Maritime Organization (IMO), headquartered in London, is a specialized agency of the United Nations which is responsible for measures to improve the safety and security of international shipping and prevent marine pollution from ships. It also is involved in legal matters, including liability and compensation issues and the facilitation of international maritime traffic. It was established by means of a Convention adopted under the auspices of the United Nations in Geneva on 17-March 1948 and met for the first time in January 1959. It currently has 165 Member States.

  • IMO Resolution MSC.74(69), Annex 3, RECOMMENDATION ON PERFORMANCE STANDARDS FOR AN UNIVERSAL SHIPBORNE AUTOMATIC IDENTIFICATION SYSTEMS (AIS). This standard defines the basic performance requirements for AIS equipment, and was used by International Telecommunications Union and International Electrotechnical Commission in developing technical and test standards.
  • IMO Resolution A.1106(29), REVISED GUIDELINES FOR THE ONBOARD OPERATIONAL USE OF SHIPBORNE AUTOMATIC IDENTIFICATION SYSTEMS (AIS). This 17 page guideline, which supersedes IMO Resolutions A.956(23) and A.917(22), provides and promotes the safe and effective use of shipborne Automatic Identification Systems (AIS), in particular, it informs the mariner about the operational use, limits and potential uses of AIS. Consequently, and per 33 CFR 164.46(a), AIS should be operated taking into account these guidelines.
  • IMO Resolution MSC.347(91), RECOMMENDATION FOR THE PROTECTION OF THE AIS VHF DATA LINK. Which recommends that: any device which transmits on the radio channels allocated for AIS, should meet the appropriate requirements of Recommendation ITU-R M.1371;  that all such transmitting devices should be approved by the Administration; and, that Administrations should take the steps necessary to ensure the integrity of the radio channels used for AIS in their waters. Supersedes IMO Resolution MSC.140(76).
  • IMO Marine Safety Circular 1252, GUIDELINES ON ANNUAL TESTING OF THE AUTOMATIC IDENTIFICATION SYSTEM (AIS) {Unified Interpretation}. Although annual testing of AIS is not currently required in the United States, AIS equipped vessels navigating internationally should abide by SOLAS Regulation V/18.9 and this Guideline. Not doing so may impact a vessel’s entry into a foreign port and possibly subject it to other actions. Domestic AIS users are encouraged to test their AIS on regular basis. To assist users in doing so the U.S. Coast Guard, Federal Communications Commission (FCC) Wireless Bureau, and, Radio Technical Commission for Maritime Services (RTCM) have collaborated in this USCG AIS Inspection Checklist; which mirrors much of what is this Circular, but, also takes into account U.S. AIS requirements and the USCG AIS Encoding Guide. To inspect what your AIS is broadcasting, use our Vessel Information Verification Service (VIVS).
  • IMO Marine Safety Circular 1473, POLICY ON USE OF AIS AIDS TO NAVIGATION

International Association of Lighthouse Authorities

The International Association of Lighthouse Authorities (IALA) is a non-profit making international technical association, and a lead organization in the advancement, development, and, use of AIS. Established in 1957, it gathers together marine aids to navigation authorities, manufacturers and consultants from all parts of the world and offers them the opportunity to compare their experiences and achievements. Through the work of its Committees it develops common standards through publications of IALA Guidelines and Recommendations, such as AN OVERVIEW OF AIS and those listed below.

IALA Guidelines, provide detailed, in-depth information on an aspect of a specific subject, indicating options, best practices and suggestions for implementation.
 IALA Recommendations, provide direction to IALA members on uniform procedures and processes that will facilitate IALA objectives.

International Electrotechnical Commission

The International Electrotechnical Commission is the leading global organization that prepares and publishes international standards for all electrical, electronic and related technologies. These serve as a basis for national standardization and as references when drafting international tenders and contracts. Through its members, the IEC promotes international cooperation on all questions of electrotechnical standardization and related matters, such as the assessment of conformity to standards, in the fields of electricity, electronics and related technologies.  The respective IEC standard that defines the certification test requirements for each type of AIS station is denoted at our ‘Type of AIS’ page.

International Telecommunications Union

The International Telecommunications Union (ITU), headquartered in Geneva, Switzerland is an international organization within the United Nations System where governments and the private sector coordinate global telecom networks and services. The Union was established last century as an impartial, international organization within which governments and the private sector could work together to coordinate the operation of telecommunication networks and services and advance the development of communications technology. While the organization remains relatively unknown to the general public, ITU's work over more than one hundred years has helped create a global communications network which now integrates a huge range of technologies, yet remains one of the most reliable man-made systems ever developed.

  • ITU-R Recommendation M.1371 series, TECHNICAL CHARACTERISTICS FOR A UNIVERSAL SHIPBORNE AUTOMATIC IDENTIFICATION SYSTEM USING TIME DIVISION MULTIPLE ACCESS IN THE MARITIME MOBILE BAND. The International Telecommunications Union Sector for Radiocommunications formally adopted this standard in August 2001.  This is the standard that defines in detail how the AIS works, and as such is the primary AIS standard.  It is available electronically at no charge from ITU.