Glossary of SCUBA Diving - E

E

ear clearing

Equalising the pressure in the middle and external ear by opening the Eustachian tubes. Several techniques are used.

ECCR

Electronic closed circuit rebreather. Sometime ECCCR for electronically controlled closed circuit rebreather.

eddy current test

Use of electromagnetic induction to detect flaws in conductive materials. It is used to detect cracks in parallel neck threads of aluminium cylinders. Also called Visual Plus inspection. Required for cylinders of AA6351 alloy.

EDTC

European Diving Technology Committee. The EDTC aims to make European professional diving safer..

E-L algoritm

also Thalmann algorithm

Exponential-Linear algorithm of 2008 US Navy tables, assumes exponential ingassing and a combination of linear and exponential outgassing rates.

electro-galvanic oxygen sensor

An electro-chemical fuel cell which produces a voltage proportional to the partial pressure of oxygen.

emergency position indicating radio beacon

also emergency beacons or EPIRB,

Emergency position-indicating radio beacons are tracking transmitters which aid in the detection and location of boats and people in distress at sea.

EPIRB

see emergency position indicating radio beacon

equalise

Balance pressure of a gas filled space with the ambient pressure, by adding or venting gas, to prevent barotrauma or pressure damage.

equivalent air depth

also EAD

A way of approximating the decompression requirements of nitrox mixtures at depth by comparison with the depth at which air would require the same decopression.

equivalent narcotic depth

also END

A way of expressing the narcotic effect of a breathing gas mixture at depth by comparison with the depth at which air would have a similar effect.

exceptional exposure

A dive in which the risk of decompresssion sickness, oxygen toxixity, and/or exposure to the elements is substantially greater than on a normal working dive.

exursion umbilical

The combined supply and return hoses and cables for life-line, life-support, power and communications between a diving bell and the diver