Kirby Morgan® Dive Systems, Inc. (KMDSI) was alerted by its Authorized Dealer in Southern Africa about the following incident: A Kirby Morgan® SuperLite® 17A/B (Serial #82929, purchased in April 1997) neck clamp assembly was found jammed in a container door. The neck clamp was hanging on the umbilical rack on the door and the person closing the container door did not notice that it was jammed. When the jammed neck clamp was discovered, it was removed and closely inspected. During the clamping process (onto the helmet) one of the welded pins on the neck clamp assembly broke off. On closer inspection it was noted that there was no way of identifying this potential break as both sides of the pin are welded.
It is important that a visual inspection of the neck clamp assembly be done before every dive. Normal inspection of the neck clamp assembly is covered in the Kirby Morgan® Daily Pre-Dive inspection Appendixes A2.3, Monthly Inspection A2.2 and the Annual / 400 Hour Overhaul A2.1.
The Annual/400 hour Overhaul has the technician remove the clamp from the yoke and neck dam so that all the component surfaces are revealed for inspection. The monthly Inspection check has the technician checking all welds and checking the entire clamp adjustment stud by loosening the lock nut and exposing the entire stud. This check is not as complete as the annual but is considered adequate if done monthly. Neck clamps older than five years should be inspected weekly in accordance with Appendix A2.2 steps 1-6 and daily in accordance with Appendix A2.3 Daily Pre-Dive Set up and Inspection steps 1.1-1.2. Anytime neck clamps are used on different helmets the neck clamp must be checked for proper function, fit and adjustment prior to diving.
Over the years, KMDSI has upgraded and enhanced the SuperLite® 17 A/B, MK 21 neck clamp assembly. Enhancements include not only more stringent inspections, but reinforcements in critical areas as well as changing materials to aid in the reduction of oxidizing. Since April, 1999 KMDSI has inscribed every SuperLite® 17 A/B, MK21 neck clamp with date of manufacture and an identification number.
April 2004 will be five years since the inception of inscribed neck clamps. If your neck clamp is not inscribed, it is older than five years and KMDSI strongly recommends that the neck clamp be inspected on a weekly basis in accordance with SuperLite® 17 A/B monthly helmet inspection Appendix A2.2 procedures 1 6.
Any Neck Clamp Assembly that does not pass inspection and is not repairable should be destroyed so that there is no chance of it being used by accident or negligence.