Overview
EN ISO 24805:2022 - Recreational diving services - Requirements for rebreather diver training (ISO 24805:2022) defines training and evaluation requirements for rebreather diver training for decompression diving. It covers competencies to perform dives using a closed- or semi-closed rebreather to 40 m with nitrox or to 45 m with trimix, where mandatory decompression stops are required. The standard specifies both the knowledge and practical-skill criteria and the conditions under which training must be delivered, complementing the general recreational diving service requirements in ISO 24803.
Key topics and requirements
The document sets out structured requirements for a rebreather diver training programme, including:
-
Competency and evaluation criteria
- Defined learning outcomes for theoretical knowledge and practical skills
- Formal evaluation methods and proof of qualification
-
Prerequisites for trainees
- Minimum age, diving experience and health/fitness prerequisites (as required for safe decompression rebreather diving)
-
Theoretical knowledge areas
- Rebreather basics and function of components
- Breathing performance, gas supply and CO2 absorbent duration
- Rebreather assembly, pre-water entry checks and maintenance
- Decompression theory and techniques for planned decompression dives
- Gas-related hazards: hypercapnia, hypoxia, hyperoxia and CO-related issues
- Buddy system and dive conduct protocols
-
Practical skills and training parameters
- Pre-dive procedures, in-water dive conduct and post-dive procedures
- Emergency responses, malfunction management and rescue procedures
- Minimum in-water training sessions and instructor responsibilities
- Breathing gas limits for closed-circuit and semi-closed rebreathers
-
Instructor, equipment and documentation
- Requirements for instructors, training equipment, materials and record-keeping
Applications
EN ISO 24805:2022 is designed to be applied by organizations and professionals involved in advanced recreational rebreather diving, including:
- Dive training agencies and rebreather instructor programmes
- Dive centres and recreational diving service providers running decompression rebreather courses
- Certification and quality-assurance bodies that assess training programmes
- Dive safety officers, operators and experienced divers transitioning to trimix decompression dives
Using the standard helps ensure consistent, safety-focused training, clear evaluation of diver competence, and harmonized certification for decompression rebreather operations.
Related standards
Keywords: EN ISO 24805:2022, ISO 24805, rebreather diver training, decompression diving to 45 m, trimix, nitrox, recreational diving services, rebreather competency, dive training standard.
