Climbing Harness

A climbing harness is a piece of equipment used in certain types of rock-climbing, abseiling or other activities requiring the use of ropes to provide access and/or safety (eg industrial rope access, working at heights, etc.). A harness is used to secure a person to a piece of rope or an anchor point of some kind.
In its simplest form a harness can be fashioned from a length of rope or a nylon tape sling tied round the waist and attached to the rope, usually by means of a carabiner. More sophisticated harnesses exist in many different patterns, designed to give greater comfort and security, and to provide more options for carrying equipment.
There are three main kinds of harnesses.
Sit Harness
A sit harness comprises a waist belt and two leg loops which are normally connected in the front of the hips either through a permanent webbing loop (sometimes called a belay loop) or through the use of a carabiner.
These harness are the most commonly used for recreational activities such as abseiling or rock-climbing as a wide range of movement is afforded whilst still maintaining a good level of safety.
Chest Harness
A chest harness is worn around the shoulders. These harness are not used on their own, but normally in conjunction with a sit harness so as to provide an additional attachment point further up the body. This additional attachment point can prove valuable in some circumstances as it allows for better balance when carrying a heavy pack (as the centre of mass is well below the connection to the rope) or where the person in the harness may be unable to maintain an upright position (due to injury or other influences).
Full-body Harness
A full-body harness is most commonly used in industrial/rescue situations. In essence is it the combination of a sit harness and a chest harness which are permanently or semi-permanently connected to each other. These harnesses normally offer a very extensive range of attachment points allowing for safe positioning in a number of positions.
Whilst these harnesses can be improvised as mentioned earlier, it is recommended that a commercially produced harness be used wherever possible. This is because there are stringent guidelines surrounding the manufacture of harnesses, and as such a store-bought harness is safer and often more comfortable than an improvised one.