Precaution and safety with dive computers
In the past, divers explored beneath the ocean's surface with little more than a suit, air tanks and a weight belt. The idea seemed almost romantic. Unfortunately, the ocean's depths contain a variety of potential hazards for even the most experienced and savvy divers. Today, many divers are armed with dive computers. These small computers attach to their wrists like a watch and help divers accurately monitor the time they've been submerged and their distance from the water's surface. By measuring these factors, divers can prevent making themselves vulnerable to decompression sickness. Though mildly less-romantic, dive computers help to ensure a diver's safety.
Why you need a dive computer
When divers prepare for a dive, they used to consult decompression cards. These cards showed tables that reflected the elements for a particular dive profile. Using a mathematical formula, these decompression tables listed the breathing gas needed and the decompression stops required during the dive. However, these formulas are based upon variables that may stray from the norm. For example, a decompression stop may accidentally be missed. The diver's depth may be slightly different than the tables allow for a dive profile. These changes could potentially mean that inert gases that have been absorbed into the body aren't being eliminated effectively. When this happens, a diver may be vulnerable to decompression sickness.
A dive computer makes continuous adjustments based on the time that has elapsed while underwater and the current depth of the diver. By making these calculations and adjustments, the dive computer can advise the diver on the pressure experienced within his body from the buildup of inert gases. By doing this, a diver can make whatever adjustments are necessary to make himself less-susceptible to decompression sickness.
Types of information available
A diver's computer is capable of displaying much more information than merely the depth of the diver and the time that has elapsed since submerging. It can also keep track of a dive's maximum depth, water temperature and the required decompression stop depth and time. If a diver is using a pressure sensor attached to his diving cylinder, his computer can also display the gas pressure and how much time he has left. This is based on how much gas remains within his tanks and the rate at which he's using the gas. Though much of this additional information isn't considered critical, many divers prefer having access to it.
How do dive computers work?
Most dive computers are straightforward. They're contained within the watertight casing and operate on batteries. By tracking the elapsed time and depth of the diver, they monitor the partial pressure of inert gases within the body. An algorithm measures the pressure of gases and their absorption into the body's tissues along with the dive profile. This allows the computer to calculate the rate of ascent and stops required to avoid decompression sickness.
Dive computers don't prelude precaution
Keep in mind that you shouldn't neglect to plan your dive simply because you're using a dive computer. Diving requires both discipline and training. A dive computer doesn't make either irrelevant. Take the time to plan and understand your dives. Use a dive computer to calculate and adjust decompression stops and ascent rates. But don't rely completely on it. Remaining safe underwater and enjoying your diving adventures means using your head and keeping alert. Your dive computer is merely a tool. Treat it as such.