As it is very hard to test which material was used in the construction of plastic masts, OKDIA opted for a licence model.
The Class Rules are:
12. MAST12.1 Materials
The spar shall be made of wood, aluminium alloy, plastic or any combination of these. For the purpose of rule 12 plastic is defined as glass fibre, carbon fibre, aramid, polyester resin or epoxy resin. An external sail track may be of any material.
The construction of the mast is optional, with the following exceptions:
- Masts constructed after 1st November 2014 using plastic or repairs and/or modifications to existing masts laying plastic over more than one meter of length shall be made by Licensed Builders
- The aft side of the sail track or groove shall be constructed straight and the line of the track or groove, extended if necessary, shall be not more than 10mm outside the aft edge of the bearing ring at the deck.
- Any cross section shape of a spar shall be in principle round, oval or teardrop in a single geometrical figure and shall have no hollows on the outside with the exception of the sail track or groove. The inside shape shall be in principle the same as the outer shape with no additional hollows.
What this means is that after 1st November 2014, anyone building or modifying a plastic mast by adding material of more than one meter in length has be licensed.
This includes professional or amateur alike, and to become licensed they must sign the Licensing Agreement.
The Licensing Agreement includes the information on the mast construction.
The licence has to be obtained BEFORE any building, repairing or alteration is done.Mast Licensing Agreement 17.10.14 (PDF, 28 KB)
This way OKDIA can ensure that the undersigning person is responsible for only using materials and methods allowed by the Agreement.
Drawing of the sticker
Additionally, licensed professional builders will attach numbered OKDIA stickers on the front of the mast, these stickers are only available from OKDIA and cannot be sold on.
From time to time OKDIA will update the list of builders on the technical website who successfully applied for a licence; this list is not necessarily complete.