The mainsail is measured with width at the top (MHB) and four widths found on the leach between head and clew: at 1/4 (MQW), 1/2 (MHW), 3/4 (MTW) and 7/8 (MUW) leech heights. Points on the leech are found by folding the sail to find equal distances between clew and head or between two adjacent measurement points.

Mainsail measurements can be provided by your sailmaker.

Symmetric spinnaker measurements include: leech length (SLU = SLE), half width (SHW) as the distance between midpoints on the luff and leech and the foot length (SFL).

Symmetric spinnaker measurements can be provided by your sailmaker.

Any spinnaker not qualifying as symmetric shall be considered as asymmetric.

Asymmetric spinnaker measurements include: luff length (SLU), leech length (SLE), half width (SHW) as the distance between midpoints on the luff and leech and the foot length (SGL).

Asymmetric spinnaker measurements can be provided by your sailmaker.

Headsail measurements are similar to those of the mainsail, including the top width (HHB) as well as four widths found on the leach between head and the clew: at 1/4 (HQW), 1/2 (HHW), 3/4 (HTW) and 7/8 (HUW) leech heights. Points on the leech are found by folding the sail to find equal distances between clew and head or between two adjacent measurement points. Additional measurements for headsails are: luff length (HLU) and luff perpendicular (HLP) as the shortest distance from the clew point to the luff.

Headsail measurements can be provided by your sailmaker.

P is the distance between the black bands on the mast (or white bands on black masts) that are limiting the position of the mainsail luff - while racing the mainsail luff must be between these bands. In the absence of an upper or lower black band, P is measured to the upper part of the main halyard sheave from the point where the top of the boom intersects the mast.

E is the measured distance from the aft side of the mast to the black band on the boom (or white band on black booms) that limits the position to which mainsail foot may be extended. In the absence of the black band, it shall be measured to the point on the boom as aft as the mainsail clew can reach.

BAS is the height from the mast datum point (at the sheerline at the mast) to the boom or lower black band on the mast. It is used also as a reference point for the halyards hoist measurements on the mast.

J is probably the best-known measurement on boat, since it is used to define the size of headsails. It is defined as the horizontal distance between the front side of the mast and the intersection of the forestay with the deck.

Spinnaker pole length (SPL) is measured when the pole is forced outboard on its fitting to the mast in a horizontal position athwarthsips, from the boat's centerline to the extreme end of the pole.

You can leave it blank if you are not using a spinnaker pole.

The tack point of spinnaker (TPS) when it is tacked on the boat's centerline is the distance from the foreside of the mast to the foremost point on which the asymmetric spinnaker can be tacked. If the bowsprit is retractable, TPS shall be measured with it in its fully-extended position.

You can leave it blank if you do not have a spinnaker tacked on the boat's centerline.

Mast profile measurements include the maximum dimensions transversely (MDT1) and fore and aft (MDL1).

IG is defined as the height of the foretriangle and is the vertical distance from the mast datum point (at the sheerline at the mast) to the forestay attachment to the mast.

ISP is the spinnaker halyard height and is the maximum height that the head of the spinnaker can be hoisted measured from the mast datum point (at the sheerline at the mast).

If the uppermost backstay is adjustable, this shall be recorded as "Aft"

If neither the uppermost backstay nor the forestay itself is adjustable, this shall be recorded as "Fixed".

If there is an inner stay, and if the tension may be adjusted, this be recorded as "Adjustable"

Select "Yes" if there is interior volume forward of the mast which is fully fitted out as a separate sleeping or living space and built of solid construction, including bunks, personal gear stowage, etc.

Select the category according to the IMS Accommodation Regulations.

If non-manual power can be used for adjusting rigging or spars, this shall be selected as follows:

"Rig & Sheet" includes "Rig" and "Sheets" together.

Hull construction shall be recorded as one of the following:

"Light": All other construction types, but excluding the incorporation of any carbon fiber.

The weight of all crew members on board while racing. If not declared a default figure is calculated and listed on the certificate.

The crew shall not be heavier than the value recorded on the certificate. The owner can always declare enough margin that will put him on safe side of this requirement.   

The weight of the complete boat in measurement trim in light ship conditions without any sails and equipment aboard. An easy explanation of lightship measurement trim would be that if the boat is rotated upside down, everything that falls out shall not be on board.

Select "Yes" if if any part of the standing rigging is made of any fiber

Select "Yes" if the mast is made of carbon.

Check this box if there is a headsail furler with HLP > 110% of J used in association with one headsail only.

Select "Yes" if there is a mainsail furler in the mast.

Select "Yes" if the mainsail and all headsails are made of woven polyester.

Insert number of spreaders

Insert number of running backstays and checkstays. The number of pairs shall be recorded.

Check this box if the mast is tapered.

Check this box if there is luff foil.