What’s a Safety Stop?

Scuba diving is regarded by some as an extreme sport and by others as an adventure sport. Those who do it probably just think of it as a hobby. It is completely safe, as long as those taking part follow a few simple scuba diving rules. Holding your breath is a big no-no, as this could cause a lung expansion injury. Touching the reef or any animals is also forbidden, both for the divers’ sake and that of whatever they touch. Diving alone and getting too low on air before deciding to end the dive are also against PADI diving rules. However, one possible danger which many people have difficulty understanding, even after having it explained to them, is the need for a safety stop, in order to avoid the serious diving-related health problem known as decompression sickness (DSC / The Bends).


A safety stop is not absolutely necessary after shallow scuba dives, but the deeper a diver’s maximum depth during the dive, the more essential safety stops become. It is also worth pointing out that repetitive dives over a period of one or more days also increases the need for a safety stop.

Imagine having a plastic bottle of Coca Cola or other carbonated drink and shaking it. Bubbles will appear inside the bottle and if you then open the lid soon or quickly, an explosion of froth will pour out of the top. To avoid this overflow of bubbles, you need to wait for a long time for the carbonated liquid to settle, or turn the lid very very slowly. This is effectively what needs to happen to your body during a PADI scuba diving safety stop.

When diving at depths of more than ten metres, breathing compressed air at depth causes inert gases to build up in a diver’s system of blood and cells. These gases are a mixture, and often include nitrogen. Coming up from depth with these gases in your system is dangerous, because your body needs time to release them – just like the Coke bottle. A typical safety stop at the end of a medium-depth recreational scuba dive involves remaining at a depth of 5 metres for a period of three minutes. This is a perfectly safe depth for your body and ideal to expel these nasty gases, and three minutes is usually long enough, provided that the dive was not too deep.

Most scuba diving sites have coral or some kind of interesting marine life near the water’s surface. Safety stops can be fun, and even go unnoticed as one explores coral and fish five metres below the waves. Dive sites in deep water, such as shipwrecks and submerged pinnacles or granite boulders often have nothing to see or do at five metres, but usually have a mooring or buoy line to hang on to. In the worst case, divers have nothing to look at and nothing to hold on to. All they can do in situations such as these is to inflate their safety sausage (a balloon to alert boats of their presence) and wait, hoping that the current isn’t too strong.
So there we have it. A safety stop is needed at the end of any scuba dive which involves the divers going deeper than 12 metres. It is to enable the diver’s body to expel unwanted inert gases, just like the need to open a bottle of Coke slowly and patiently after it has been shaken up or disturbed. Safety stops are normally performed at a depth of 5 metres and last for three minutes.