3.1 Grab Lines
3.1.1 Buoyant grablines shall be securely fitted all around the apparatus so as to provide an equal number of loops corresponding to the number of persons the apparatus is fit to support.
3.1.2 Each loop shall have a depth of not less than 150 millimetres and not more than 200 millimetres. On apparatus exceeeding 300 millimetres in overall depth two rows of grablines shall be fitted, one having its points of attachment below the top of the air cases and the other above the bottom of the air cases and as close to the sides of the air cases as practical. On apparatus of 300 millimetres or less in overall depth, one row of grab lines are to be attached along the line of the mid depth.
3.1.3 Grab lines shall be of buoyant rope of not less than 14 millimetres in diameter. They may be attached to the apparatus by being passed through holes in the framing and being interlaced to prevent movement, or attached by means of wrought iron or steel fastenings. Whichever method is adopted the attachment is to be of sufficient strength to permit the apparatus to be lifted by the grab lines.