• "Measurement" of new or modified equipment, to certify it (verify its compliance with the rules) is called "certification measurement" or simply "measurement".
• "Measurement" of equipment at sailing events to check use of equipment and verify that "certified" equipment is still in compliance with the "rules" is called "event measurement" or "equipment inspection".

"Measurers" are specialists whose function is to check sailing equipment against the relevant rules (class or rating rules).

• "Measurers" which perform certification measurement are called "official measurers" or simply "measurers". They work for a certification authority (National Authority or a Class).
• "Measurers" which perform event measurement are called "event measurers" or "equipment inspectors". They work for the Race Committee.

What is an International Measurer?

ISAF appoints officials to perform certain functions at the top level of the sport and the IM is one of these officials groups.

ISAF appoints officials to perform certain functions at the top level of the sport and the International Measurer (IM) is one of these officials groups. The main purpose of having IMs is, first and foremost, to ensure that qualified specialist race officials will lead the equipment inspections/event measurements at major Class or ISAF events. This is reflected in the ISAF Regulations: Class obligations in 10.5(g) (v), and IM appointment requirements in 31.13. Other official functions of IMs include prototype measurement for those Classes that apply this system for their boat builders, and Class involvement as per ISAF Regulation 10.5(g) (v): in many cases, the chief measurer of a Class is an IM of that Class.

All IMs are specialists in one or more Classes (the term "class" includes rating systems) with excellent knowledge of i) the relevant class rules and ii) certification measurement and high level inspection methods & techniques. Additionally, all IMs who have been through the current seminar/testing system can be thought of as "ERS-certified", which means they have been trained to both measure and inspect equipment that follows the ERS, no matter which Class they are appointed for as IMs.

The normal pathway for IMs is to start from their MNA and/or Class system ("national measurers") to get the necessary experience and basic knowledge about "measurement", and progress to the ISAF appointment when both their knowledge and experience in event measurement/inspection reach a high level.

Most IMs today are also what the ERS defines as "official measurers", but only when they are appointed as such by their MNAs or Classes, and not because of their IM title. And since they are considered as top level "measurers", many IMs play an important role in their MNA technical systems as well.

As with all ISAF race officials, the conduct of IMs at events is regulated by the ISAF Race Officials Code of Conduct and the Conflict of Interest guidelines.

The current IM training and testing scheme is designed -among other things- to provide IMs with the necessary level of knowledge about:

• ERS and their practical application including certification measurement techniques (even for those IMs for Classes that do not apply the ERS, and for those Classes which don't need certification measurement).
• Class-independent Equipment Inspection principles and techniques.
• Leading an Equipment inspection team as Chief Measurers/Chief Equipment Inspectors at major single or multi-class events.

Class-specific knowledge and training is still the responsibility of the respective Classes, and should include high level inspection procedures adapted to their specific needs.