The wire must be strong enough to prevent the valve handle from being accidentally shut. However the wire must be weak enough so that the average person can break the wire with the valve handle when closing the valve. It is important to lubricate o-rings during installation to ensure proper function and to prevent leaks. Lack of sufficient lubrication can result in o-ring failure as a result of excessive friction or heat. When lubricating o-rings for use in diving systems just remember that more is not better.
Excessive lubrication can cause problems in a diving system.
Extra lubricant will travel through the system and it can build up on component parts such as the regulator. After a period of time, the regulator or some other component could fail as a result of build up of excessive lubricants. A build up of lubricants can also hamper the flow of the gas. There should only be enough lubricant on the o-ring to present an even sheen on all surfaces. Any excess should be wiped off the o-ring.