46 CFR 160.002-4 - Construction.
(a) General. This specification covers life preservers which essentially consist of a vest-cut envelope containing pockets in which are enclosed pads of buoyant material, the life preserver being fitted with tapes and webbing to provide complete reversibility, proper adjustment for close fit to the bodies of various size wearers, and proper flotation characteristics to hold the wearer in an upright backward position with head and face out of water.
(b) Envelope. The envelope shall be of not more than two pieces, one piece for either side, cut to the pattern shown on Dwg. No. F-49-6-1, Sheet 1, for adult size, and Dwg. F-49-6-5, Sheet 1, for child size, joined by seams and stitching as shown on the drawing. A drawstring tunnel shall be formed by stitching a strip of the tunnel strip material as shown on the drawing. The ends of the tunnel strip shall be tucked under the reinforcing tape stitched around the end openings so there is no direct access to the pads from the outside. Three pockets shall be formed for insertion of the kapok pads. The two front pads shall be removable from the envelope when portions of the lower longitudinal seam are opened, and the back pad shall be removable when a portion of one armhole seam is opened.
(c) Pad inserts -
(1) Forming, sealing, and distribution of kapok. The buoyant pad inserts shall be formed from two pieces of film cut to the patterns shown by Dwg. No. F-49-6-1, Sheet 2, for adult size, and Dwg. No. F-49-6-5, Sheet 2, for child size, which shall be heat-sealed tight. The heat-sealed pad seams shall show an adhesion of not less than 8 pounds when one inch strips cut across and perpendicular to the seams are pulled apart at a rate of separation of the clamping jaws of the test machine of 12 inches per minute. The pad inserts shall be filled with kapok distributed as follows:
Table 160.002-4 (c)(1) - Distribution of Kapok in Pad Inserts
|Model 3 (minimum)||Model 5 (minimum)|
|Front pad (2):|
|Lower section||5.25 oz. each||3.50 oz. each.|
|Upper section||3.75 oz. each||2.50 oz. each.|
|Back Pad||6.00 oz.||4.00 oz.|
|Total||24.00 oz.||16.00 oz.|
(2) Displacement of pad inserts. The volume of the finished individual heat-sealed buoyant pad inserts shall be such as to provide buoyancy as set forth in the following table when tested in accordance with the method set forth in § 160.002-5(d), except that the period of submergence shall be only long enough to determine the displacement of the pads:
Table 160.002-4(c)(2) - Volume Displacement of Sealed Pads
|Model 3||Model 5|
|Front pads||12 1/2 lbs. each ± 3/4 lb||6 1/2 lbs. each ± 1/2 lb.|
|Back pads||8 lbs. each ± 1/2 lb||4 1/2 lbs. each ± 1/2 lb.|
(d) Tie tapes. The tie tapes at the neck shall extend not less than 14 inches from the edge of the adult life preserver and not less than 12 inches from the edge of the child life preserver. They shall be stitched through both thicknesses of the envelope as shown by Dwg. No. F-49-6-1, Sheet 1, for adult size, and Dwg. No. F-49-6-5, Sheet 1, for child size, or by the alternate stitching shown on Sheet 1A. The free ends shall be doubled over and stitched in accordance with section G-G of Sheet 1.
(e) Drawstrings. The drawstrings at the waist shall extend not less than 8 inches from the edge of the life preserver and shall be secured in the drawstring tunnel as shown by Dwg. No. F-49-6-1, Sheet 1, for adult size, and Dwg. No. F-49-6-5, Sheet 1, for child size, or by the alternate stitching shown on Sheet 1A. The free ends shall be doubled over and stitched in accordance with section G-G of Sheet 1.
(f) Body strap. The body strap shall be fitted with a single Dee ring on one end with the arrangement of a snap hook and pre-threaded double Dee rings as shown on Dwg. No. F-49-6-1, Sheet 1, on the other. The body strap shall be stitched as shown on the drawings, and the edge of the single Dee ring shall be 20 inches from the center line for adult size and 15 inches for child size.
(g) Reinforcing tape. Binding tape shall be stitched approximately 15 inches for adult jackets and 12 inches for child jackets around the back of the neck, and also around the openings of the drawstring tunnel and around the bottom of the armholes, as indicated by the drawings.
(h) Stitching. All stitching shall be a short lock stitch conforming to Stitch Type 301 of Federal standard No. 751 and there shall be not less than 7, nor more than 9 stitches to the inch.
(i) Workmanship. Life preservers shall be of first-class workmanship and shall be free from any defects materially affecting their appearance or serviceability.