Some specialties present special hazards or safety considerations, and certification is required prior to participating in them. These include:

• Nitrox
• Cave and cavern diving
• Wreck penetration
• Ice diving
• Technical diving
• Rebreathers

These specialty courses cover the equipment, safety precautions, and special skills required to safely participate in these activities. This training is essential for your safety, which is why dive operators and retailers will not sell equipment or trips related to these activities without proof of specialty training.