SPG (Submersible Pressure Gauge)
Know how much air is left in the tank. A SPG can be separate or built into a dive computer and are made in both analog and digital.
What is no decompression time?
The “no-decompression limit” (NDL) or “no-stop limit” , is the time interval that a diver may theoretically spend at a given depth without having to perform any decompression stops while surfacing.
What are the ABC of scuba diving?
ABC stands for: A – Air. B – Buoyancy. C – Clips and releases.
How is PPO2 calculated?
You can find it by multiplying the oxygen percentage of the EANx by the absolute pressure (in atmospheres or bar). For example, a diver breathing air (21 percent O2) at 132 feet (5 ata) is breathing a partial pressure of oxygen (PPO2) of 1.05. This would be equivalent to breathing 105 percent oxygen at the surface.
What is a SPG in scuba? – Related Questions
What is the 40% rule in nitrox diving?
In essence, the 40 Percent Rule states that, if a regulator, cylinder or valve will not be exposed to gas mixtures with an FO2 greater than 40 percent, at pressures greater than regulator intermediate pressure, they need not be O2 clean or service rated.
How deep can you go on 32% nitrox?
Based on the 1.4 ATA limit, a nitrox mix with 32 percent oxygen has an MOD of 112 feet, and 36-percent nitrox has a maximum depth of 95 feet.
What is the maximum ppO2 allowed in treatment gas during a recompression treatment?
Technical divers often use a maximum of 1.6 ATA partial pressure of oxygen (ppO2) for a safe oxygen limit underwater during planned decompression, whereas recreational divers usually prefer a more conservative limit of 1.4 ATA.
What is the maximum oxygen partial pressure limit?
When scuba diving, you always want to keep your oxygen partial pressures between 0.16 (16%) and 1.6 (160%). If you fall below or go above this range you risk serious injury and death. Even on air, foolish people can exceed a partial pressure of 1.6.
How do I calculate gas for diving?
To estimate your total gas needs for the dive, take the starting pressure of your cylinder, subtract a reserve amount of gas and then divide the remainder by the consumption rate to find out how many minutes of dive time you can expect.
How is Nitrox EAD calculated?
EAD = (Depth + 33) × Fraction of N2 / 0.79 − 33. Working the earlier example, for a nitrox mix containing 64% nitrogen (EAN36) being used at 90 feet, the EAD is: EAD = (90 + 33) × 0.64 / 0.79 − 33. So at 90 feet on this mix, the diver would calculate their decompression requirements as if on air at 67 feet.
Can you stay down longer with Nitrox?
Many people think that nitrox allows you to dive deeper and stay down longer, but this is simply not true. Nitrox is a shallow-diving gas. While it can extend no-decompression limits (NDLs) compared with air, you still breathe at the same rate, so you’ll still breathe the tank down at the same rate.
Can I fill my Nitrox tank with air?
Filling a Nitrox tank with air is possible. However, once you do the tank is no longer safe to be used for Nitrox until it has been oxygen serviced. Any tank having a standard air fill will need to be serviced before using EAN. If you plan on using both air and Nitrox, it may be best to get a second tank.
Does nitrox certification expire?
The short answer is forever! Once your instructor submits the certification paperwork, your PADI card is valid forever and recognized internationally. This rule applies to all recreational PADI courses, including Junior Diver, Open Water Diver, Advanced Open Water Diver, Rescue Diver, and NITROX Diver.
What is the highest diving certification?
Master Scuba Diver (sometimes referred to as “MSD”) is the highest level of recreational diving. Above all, to become a PADI Master Scuba Diver™ you must: Hold an Open Water Diver, Advanced Open Water Diver and Rescue Diver certification.
Is PADI Nitrox worth it?
If you fancy staying down longer and getting back in the water sooner, then yes; getting nitrox certified is worth it. You can take more photos, wave to more turtles, and spend more time exploring. Many divers wait too long to try nitrox.
Is it easier to breathe Nitrox?
Because there is less nitrogen in the air your breath less nitrogen will be absorbed which gives you more time at depth compared to regular air. The second benefit of diving with Nitrox is that you can use Nitrox to plan more conservative dives.
Why doesn t everyone dive with nitrox?
The reason for this warning has to do with a little problem known as oxygen toxicity. Believe it or not, oxygen, which we need to stay alive, can cause a diver to convulse when pressure increases on descent. This generally happens when the partial pressures of oxygen exceed 1.6 atmospheres.
When not to use nitrox?
For dives below 130 feet, EAN provides no advantage to recreational divers. In fact, because of the increased partial pressure of oxygen, NOAA Nitrox I cannot be used safely below 130 feet. And NOAA Nitrox II can’t be used safely below 110 feet.
Why is nitrox called nitrox?
The term “nitrox” was originally used to refer to the breathing gas in a seafloor habitat where the oxygen has to be kept to a lower fraction than in air to avoid long term oxygen toxicity problems.
Why is oxygen toxic at depth?
Oxygen toxicity happens when our body’s protective systems are affected by increases in oxygen partial pressure. The tissue-protective mechanisms and biochemical reactions of our bodies are tuned to life in an atmosphere containing 21 percent oxygen, or 0.21 atmospheres absolute (ATA) oxygen partial pressure.