Getting the ‘thumbs up' sign is probably the worst signal any diver can receive since it signifies that the dive has ended. Extending time, and sometimes depth, in water is probably every divers desire.

The RAID DECO 40 program forms a bridge between recreational and technical diving. The problem with technical diving is that it has marketed and positioned itself as unattainable for the average diver. Divers are led to believe they must have superhuman strength and mental agility to participate in a technical diving program. Of course, here at RAID we believe this is simply not the case, but believing and acting are two totally different things.

The Deco 40 program is aimed squarely at the recreational market and not at the technical market. The program is ideally completed using modified recreational equipment.  The Deco 40 makes an ideal entry-level decompression program, but it must be noted that it has been created with the recreational diver in mind.

What is involved in the course and what must I do?

- There are 6 eLearning sections to complete - equipment, physics, physiology, management, confined water & open water 
- One confined water skill session
- Five hours open water training dives

- As this course is aimed at recreational divers you can use a traditional BCD or wing. The only provision is that the BCD/wing needs to have D-Rings capable of attaching a side slung cylinder.
- Divers must have a 2 metre primary regulator hose
- Divers can use an optional combination of air, nitrox, trimix and/or oxygen (if certified to do so)
- Divers will complete a maximum of 10 minutes decompression.
- Divers will reach a maximum depth of 40m
- When completing a decompression dive, divers must use a bailout gas - this must be safe to breath at the maximum operating depth
- If this gas is different from the primary breathing gas, divers must use a multi-gas switch computer and perform no-decompression dives.
- Ceritify to use up to 100% Oxygen to entend no decompression dive times by using multi-level gas switch dive procedures.
- Bottom or back gas maximum PO2 is 1.4 and a maximum of 1.6 for extended no stop diving.
- When divers are switch they must use a multi-gas switch computer

*These dives can credit towards the DECO 50 course.


- Must be certified to RADI Explorer 30 or RAID Advanced 35 (or equivalent)
- Must be certified as RAID Nitrox Diver (or equivalent)
- Must be certified as RADI Deep 40 (or equivalent)
- Must have logged 40 open water dives on open circuit
- Must be minimum of 16 years old and have been an active certified divers for at least 3 months
- You must have all of your own kit for this course, please speak with us for more information.

How to get started!

- Register/sign into your RAID account online at
- Assign Dorset Diving Services as your local Dive Centre (Click your RAID Profile, Select 'View or change My Dive Centre')
- Have a browse through the courses and select the course(s) you'd like to do
- Download your FREE eLearning materials and start reading
- Let us know what course(s) you have selected and we can sit down & compare diaries to get you booked into your practical training!
- Payment for your practical training is required at the time of booking and all eLearning/Quizzes/Exams must be completed the day before your first practical session.

When completing this course you maybe asked to attend either Vobster Quay/National Diving Centre, a local shore site or a boat dive. Seperate entry and parking fees may apply - these are not included in the cost of your course.
Boat dives are on Monday & Thursday evenings from 1730 onwards and depart from Poole Quay. Student spaces are £60.
Vobster Quay (Frome) will be on a weekend (or 2) at a cost of £23 per diver, per day.
National Diving Centre (Chepstow) will be on a weekend (or 2) at a cost of £22 per diver, per day. 
You will need to make your own way to the sites. Accommodation and gas prices are not included.

Our Course Terms & Conditions can be read here, by purchasing this product you agree to all Terms & Conditions.



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