Divers often experiences difficulty with buoyancy while in the begin stages of diving into the water. A diver experience difficulty with buoyancy because they is either carrying too much lead or they are not carrying enough lead to achieve neutral buoyancy. A diver that carries too much leads will find themselves sinking too quickly into the water, while a diver that dont carry enough lead will experience buoyancy in such a way that they will float towards the surface of the water.
Neutral buoyancy can be achieve by finding the correct amount of lead for that individual diver. Buoyancy is a continuous variable for divers since a persons composition, thickness of neoprene suit, and the salinity of water will change over time. A person that has high muscle and bone density will require less lead than a person with a higher body fat percentage since body fat is more buoyant than muscle and bone.
How to Get Neutral Buoyancy When Diving
A person can calculate their weight by using a percentage of their total body mass. This calculate for the lift that a person may experience from their diving suits. Thin three-millimeter diving suits will have little lift, but suits that is seven-millimeter in thickness or who wear a full drysuit will experience a large amount of lift.
The air that becomes trapped in these thick suits create the lift that a person experiences in these thick diving suits. Because this force act upon a person in water, counterbalancing lead must be used to ensure that a person does not drift lateral in their dives. Another factor in lead placement is in achieving horizontal trim in the water.
Horizontal trim is the state where a person is level in the water. A person can wear a weight belt around their hips, but if all of the lead is place in one location, a head-down angle will result. Using Buoyancy Control Devices (BCDs) allow a person to place their lead in different part of the device, such as front weight pockets and rear trim pockets.
A person will want to use ankle weights to ensure that their feet does not float towards the surface of the water, but trim weights can be moved to the rear trim pockets to ensure that a persons head does not dip towards the bottom of the dive. Lead blocks that is hard in composition are used for weight belts, but soft weight are required for the pockets of an integrated BCD. The environment in which a person is diving for will also change the amount of lead require by that person.
The salinity of the water will impact the lead requirements of a divers. Saltwater is more dense than freshwater, creating a force that push a person towards the surface more in saltwater than freshwater. Therefore, a person who was appropriately weighed for saltwater dives may be overweighted when diving in freshwater.
To test a diver’s buoyancy, a diver can utilize the hover test. During a hover test, a person should be floating motionless at a depth of fifteen feet with an empty BCD and with half the capacity of the persons lungs. During this test, a person may find that their buoyancy is not balance, in which case they should adjust their lead.
However, small adjustment should be made to a persons lead to avoid overcorrecting their buoyancy. Only two pounds of lead should be move at a time to allow for this control in divers. However, other factors impact buoyancy, such as the weight of the persons scuba diving tank.
Aluminum eighty tank diving tanks become more buoyant when the person breathe all the air out of their tank. In this case, a person may start their dive with neutral buoyancy but may find their body can no longer maintain neutrality towards the end of their dive. Finally, these factor should be documented in a dive log to track changes in a persons dive tank, body composition, and the type of water they dive in to manage lead requirement in the future.
