IOM More Information

Link to the latest version of the IOM Class Rules, Technical Interpretations & Measurement Forms

Link to the IOMICA international forum


Technical Interpretation

Mar 31st – In response to a request for Technical Interpretation surrounding a combined kicker/outhaul/vang/sheeting device, the IOMICA has issued this bulletin.

Class News

Feb 28th – The new IOM Class rules have now been published and take effect March 1st, 2015.  The only changes in the 2015 edition of the IOM Class Rules are those related to two emergency rule changes in 2014 dealing with tell tales and headsail topping lift restraint line(s).  and click on the IOM Class Rules 2015 link at the top of the page.

To download the various measurement certification forms and check lists and rig forms, scroll to the bottom of the Class Rues page and click on the appropriate items.

The Class Rules Page also has links to rules interpretations going back to 2003.


New IOMICA Rulings 

Sept 11th  The UK submitted a request for a Technical Committee interpretation of the IOM Class Rule relating to the use of a restraining loop or elastic restraint on the Jib Boom topping lift. Several variations were shown. The restraint is used to prevent the topping lift from catching on the spreaders. The Questions and the official reply can be seen at

Basically, the answer is that various kinds of restraint in common use are class legal, BUT you cannot use more than one method at a time..