Specialty certifications: what needs its own course.

How specialities fit the ladder

Advanced courses often work as a sampler. PADI's Advanced Open Water Diver and SSI's Advanced Adventurer each include single Adventure Dives in several specialities. SDI says one dive from each Advanced Adventure Diver speciality may count towards the full speciality certification, and that junior divers may take only the specialities approved for their age. A full speciality is a separate course with its own card.

This page lists which activities the agencies teach as separate courses and the entry ages and prerequisites they publish. It does not describe the skills, gas rules or planning limits those courses teach. All ages are the named agency's own statement. PADI's deep diving figures are from its blog updated 16 August 2024; the SSI, NAUI, SDI, TDI and GUE course pages cited here carry no date (we read them in October 2026), so their figures are undated.

Deep diving

Deep diving is a separate certification at PADI (Deep Diver, to 40 m / 130 ft), SSI (Deep Diving, 18 to 40 m), NAUI (Deep Diver, 18 to 40 m) and SDI (Deep Diver, deeper than 18 m to 40 m). PADI lists a minimum age of 15 and requires Open Water Diver and Adventure Diver or equivalents. NAUI requires Advanced Open Water Scuba Diver or an equivalent. SDI lists 18, or 10 with parental consent. Each agency's figures are compared on depth limits by certification.

Enriched air nitrox

Wikipedia (secondary) says the US RSTC publishes a separate minimum standard for Enriched Air Nitrox certification. On its history, Wikipedia says IAND began teaching nitrox for recreational diving in 1985, NAUI was the first major recreational agency to sanction it in 1992, and PADI announced full educational support in 1996. BSAC says it approved nitrox for its members in 1995, and that basic nitrox training is now part of its Ocean Diver course. SSI lists ISO 11107, the standard for enriched air nitrox diver training, among the ISO standards its programmes align with.

PADI's Enriched Air Diver page could not be opened during our research. A search summary of it gave a minimum age of 12 and said the course can be earned as part of Open Water Diver; an Australian retailer lists 16 for the same course. We could not confirm either figure. The equipment side is covered on nitrox equipment.

Dry suit

Agencies teach dry suit diving as its own speciality. SDI sets a minimum age of 12 for its dry suit speciality. GUE runs a separate Drysuit primer that does not require GUE Fundamentals. Two snapshots of SSI's dry suit page, seen in search summaries, disagree: one gives a minimum age of 12 with Open Water Diver as the prerequisite, the other gives 10. PADI's Dry Suit Diver page could not be opened, so its terms are not given here. For the suits themselves, see dry suits.

Wreck

SDI sets a minimum age of 15 for its wreck speciality, which it describes as involving limited penetration. PADI's own Wreck Diver course page did not surface in our research, so we give no minimum age or prerequisite for it.

Cavern and cave

Cavern and cave diving take place in overhead environments, and agencies keep them separate from open water training.

• TDI Cavern Diver: minimum age 18, or 15 with parental consent, plus SDI Open Water Scuba Diver or an equivalent and 25 logged dives. TDI says the course covers cavern environments and is not meant for cave diving.
• TDI Intro to Cave Diver: requires TDI Cavern Diver or an equivalent, with a minimum age of 18, or 15 with parental consent. It leads on to TDI Full Cave Diver training.
• GUE: its technical and cave courses are entered through a technical endorsement on GUE Fundamentals, which has a minimum age of 16.

Cave diving also has its own organisations. The National Speleological Society Cave Diving Section (NSS-CDS) says it was formed in 1973, with Sheck Exley as its first chairman, and that it had become the world's largest cave diving organisation by 1976 and has stayed so; that is the organisation's own claim. It says its first instructor institute was held in Branford, Florida in 1980.

Technical diving

Wikipedia (secondary) describes technical diving as recreational scuba beyond the generally accepted recreational limits. TDI says it was founded in 1994 to provide specialised training beyond sport diving, and GUE's original 1998 course list was built around cave, technical and rebreather diving. TDI lists its Intro to Tech Diving with a minimum age of 18, or 15 with parental consent, plus SDI Open Water Scuba Diver or an equivalent and 25 logged open water dives, and describes it as an introduction that builds on recreational training. Some TDI dive centres list the minimum age as 15 without mentioning parental consent. SSI names Decompression Diving and SSI Extended Range among its programmes beyond the recreational range.

Rebreathers

Rebreathers recycle exhaled gas instead of releasing it as bubbles. BSAC says it approved rebreathers for members in 2001 and introduced rebreather and mixed gas courses in 2005. RAID, according to Wikipedia (secondary), was founded in 2007 specifically to train divers on one rebreather model, the Poseidon Mk VI Discovery, before adding other courses.

Prerequisites stack up

Most of these courses require an earlier card, a number of logged dives, or both, and SDI says junior divers may take only the specialities approved for their age. The ladders they sit on are set out on certification levels.