Extended range

C-Life Dive School

Celebrating quality and service for 22yrs 

PSA or TDI - Extended Range - £360 - 3 Days

This course provides the skills for Deep Air Diving with the use of more than one Rich Nitrox Mix (up to 100%) as decompression gas. The course covers further equipment configuration for deep diving (more stages differing sizes), trapeze use, and the use of advanced decompression equipment (obligatory emergency extra deco gas for team). Plus new training skills when working with different 'Team' sizes to challenge your personal stress limits, Narcosis Management, improve and build experience required to competently utilize air for dives up to 55msw that require staged decompression, utilizing nitrox mixtures and oxygen during decompression.

An invaluable stepping stone course which introduces alot of skills commonly used on trimix dives particually for the UK diver. ERD progresses your skills to work towards the ultimate goal of Trimix. You will be gaining the required technical experience for this level and then be more ready for the next Trimix level step. The ERD course is also a min requirement for such areas as Bikini that offer 55m dives and do not have helium for Trimix divers.

Course Format

Three-day course

One-day classroom

Two-Three days open water

Course content

Advantages & Disadvantages of richer Nitrox mixes

Narcosis Management

Review oxygen physiology and tracking oxygen uptake

Hard copy deco tables, PC generated deco tables & Dive computers

Practical Decompression skills

Decompression good practice

Equipment configuration for deep air diving & use of stage cylinders, and trapeze

Nitrox mixing and analysing gases

Advanced Dive Planning

Advantages of buddy groups and Dive Teams

Open Water DIves

Min 6 ERD dives are required with a student to instructor ratio of 3:1. 6 dives greater than 30m but less than 55m. Two of the dives must be in the 50 to 55m range.


Advanced Nitrox Diver or equivalent. 75 dives logged with 20 decompression dives deeper than 30m.