Annex IV Technical specifications of the twine thickness gauge

Gauges for assessing the thickness of twine shall:

1. (a)

   be made of durable, non-corrosive material able to withstand a harsh marine environment and shall be manufactured in accordance with the drawings shown in the figure below;

2. (b)

   have edges around the circumference of each side of the circular hole for assessing the thickness of the twine (the hole) rounded to avoid abrasion when the twine is pulled through the hole to test legality;

3. (c)

   be constructed with the nose of the pliers rounded to facilitate inserting the jaws between double twines;

4. (d)

   have jaws with parallel action that are sufficiently strong to prevent deformation of the jaws during any reasonable use, bearing in mind that the jaws have to be squeezed closed with manual force during every measurement;

5. (e)

   have the inside faces of the jaws milled to leave a 0,5 mm gap for a distance of 1 mm either side of the hole when the jaws are closed in order to avoid single filaments of material protruding from braided or twisted construction being trapped in the flat surfaces of the jaws on each side of the hole in which the twine is seated;

6. (f)

   have, when the jaws are closed, the diameter of the circular hole marked in millimetres on one of the jaws, adjacent to the hole; the jaws are closed when the surface of both internal sides of the jaws touch each other and are flush;

7. (g)

   have both the handle and the jaws marked ‘EC gauge’;

8. (h)

   have a tolerance for the hole diameter of 0 + 0,1 mm;

9. (i)

   be conveniently portable such that a set of four (4 mm, 5 mm, 6 mm, and 8 mm) gauges may be carried by an inspector during vessel to vessel transfer at sea;

10. (j)

    if gauges are of different sizes, be easily identifiable;

11. (k)

    be easy to insert between double twine. After the gauge has been inserted into position, it shall be capable of easy operation with one hand.