Tying Knots That May be Used in Scuba Diving and Boating

Tying Knots That May be Used in Scuba Diving and Boating


In scuba diving there is a need to know some basic knots. These knots may be needed underwater, or more commonly when on the dive boat.

Tying the Reef Knot
The reef knot is used to join two lengths of rope. In a scuba diving situation, this may be when needing to join two pieces of rope to form a safety line to trail out the back of the dive boat.

Take the two ends of the rope, one in each hand. Put the right hand rope over the left and twist it under and up. Then the left side end (the original right hand one) is put back over the right hand rope. Twist under and pull the knot tight.
The lay of the ropes should be symmetrical. When the two ends of the rope are pushed towards each other the knot opens up, even after a day’s hard sailing.

The best way to remember this is: 'right over left and under, then left over right and under.' The 'right' or 'left' referring to the rope end on the right or left side.

The Bowline Knot in Scuba Diving
The bowline gives a loop at the end of a rope that won't slip and is easy to undo. This knot could be used when setting up a buddy line between two divers. This is a short length of rope that each diver holds, so they don’t get separated.

A buddy line is commonly used in night scuba diving to prevent a dive buddy pair separating. It can also be used for a scuba divemaster to keep close to a nervous scuba diver.

A loop in the end of the safety line trailing out the back of the dive boat could be useful for a diver to hold on if needed.

Tying the Bowline Knot
Near the end of the rope make a small loop. This is not the size of the eventual loop. The end of the rope that goes to the right should lie on top of the end to the left.

To make the final loop, take the right hand end and bring it back and come up through the first loop. This second loop will be the final loop. Take the end that has come up through the first loop and take it under the end that comes from the left. Then around and back through the original loop.

The Figure of Eight Knot in Scuba Diving
The figure of eight knot is used to put a knot in a rope to be used as a stopper, or as a marker on a rope. It is commonly used in sailing to prevent the end of a rope from sliding through a cleat.

The knot mostly used for this purpose is the ‘granny knot’ which is a simple loop in the rope. This works fine until trying to undo the knot! After getting wet and jammed it can be impossible to undo. Pliers are sometimes needed.

In scuba diving, the figure eight knot can be used on a shot line. This is a weighted rope that is put over the side of the boat that provides an indication of the depth. A weight, like a weight belt, is attached to the end of the line, and small knots are put in the rope at specific intervals to show the depth. As the scuba diver descends, they can get an accurate idea of their depth.

This may be used for calibrating or checking depth gauges. Or maybe to accurately signify the 10 foot and 20 foot depths for decompression stops.

Tying the Figure of Eight Knot
To do the figure of eight knot, form a loop in the rope with the end going under the rope. Take the free end and go over and around the rope then up through the loop from the bottom.

When pulled tight the lay of the rope looks like the figure eight. This knot will come undone with ease, even when wet.

The basic scuba diving knots described here are some of the basics that can assist in some areas of scuba diving. Knowledge of a few knots such as these can be useful for a scuba diver.