TDI Cavern Diver course
If you lack prior technical diver training or have little or no experience diving sidemount of doubles, this is where you should start. This course combines a tech basics orientation with the skills of a traditional Cavern Diver course. There are many ways in which instructors can teach this course.
- Some teach this as a purely recreational course, with students using single tanks and purely recreational equipment. Such courses are not designed for students who wish to progress further.
- At the other end of the continuum are Cavern Diver courses specifically designed to prepare students for the rigors of cave training. This is what we offer.
Among the knowledge and skills we cover in this program:
- Basic dive planning for overhead environments
- Basic cave diver propulsion techniques
- Basic guideline and reel use
- Basic cave diver communication
- Basic emergency skills
- Advanced buoyancy control and trim
Prerequisites
The prerequisites are:
- Be at least 18 years old
- Have 25 or more dives
- Be certified to the Advanced Open Water Diver level or equivalent
- Possess Nitrox Diver certification
Additionally, you need above-average buoyancy control skills. A good way to see if you meet this requirement is to be underwater and simply stop swimming. When you do, you should instantly hover, motionless. Your feet shouldn’t sink and your knees should remain in line with your shoulders. If you can’t do this, seek remedial buoyancy control training before attempting this course.
Time frames
- The TDI Cavern Diver course takes at least two days and four dives. Depending on how quickly you learn, more time may be necessary. This generally depends on your prior experience (if any) in doubles or sidemount and any prior tech diver training you may have.
- If you require more than two days of training, we will let you know. This, however, will cost more.
- With sufficient notice, we can usually accommodate requests for specific course dates.
Required equipment
- Mask and flat-bladed scuba fins with adjustable or spring heel straps
- Adequate thermal protection for prolonged exposure to 21° C/72° F water
- A doubles or sidemount air cell and harness with adequate lift
- Two cylinders with a capacity of at least 13 liters/85 ft3 properly configured for doubles or sidemount
- Dive computer
- Slate or wet notes
- Two Z-knives or comparable cutting tools
- One primary light
- Two backup lights
- Two safety reels/spools with a total of at least 50 m/150 ft of line
Be aware than any equipment you use must meet very specific requirements. Learn more…
Items such as cylinders and primary lights, which my be difficult to travel with, are available for rental. Be sure to alert us if you will need any of these.
Choose your price
Know what you’re getting: Prices include instruction and eLearning fees. Bear in mind, the cost of eLearning, by itself, can be worth anywhere from $140 to $280 or more. Thus, a $640 course from us may actually cost the same as a $500 course from someone else if you have to pay for elearning separately.
Certification cards: We issue these only when earned. Simply taking part in a course does not guarantee certification. For cave courses, certification cards from multiple training agencies may be available. C-cards generally cost around $30 each, depending on agency. Your instructor can tell you more.
TDI Cavern Diver
For students lacking prior tech training/experience-
Two days
-
Four or more dives
TDI Cavern Diver
For students lacking prior tech training/experience-
Two days
-
Four or more dives
eLearning included at no extra charge

Computer-aided instruction is an integral part of nearly every course we teach. The Why? is simple: eLearning helps get our students in the water sooner and spend more time there. It’s why we include the cost of any applicable eLearning programs — usually a $140 value — in our courses at no extra charge. This translates directly into an extra day of in-water training. The value of that? Priceless.