| IANTD est. 1985 | |
| Stands for | International Association of Nitrox and Technical Divers |
| Contact | (305)751-4873 www.iantd.com |
| Entry-Level Certifications | Open Water Diver/Open Water Nitrox diver |
| Open-water-dives required | 4-6 for Open Water Diver; 5 for Open Water Nitrox, 2 of which must be on nitrox |
| Pool-water-dives required | 12 hours recommended |
| Lecture hours required | 12 hours recommended for Open Water; 16 for Open Water Nitrox |
| Notes | - |
| IDEA est. 1952 | |
| Stands for | International Diving Educators Association |
| Contact | (904)744-5554 www.scuba-idea.com/us |
| Entry-Level Certifications | Basic Open Water Diver |
| Open-water-dives required | 4 |
| Pool-water-dives required | Up to instructor with a minimum of 5 |
| Lecture hours required | Up to instructor with a minimum of 24 hours |
| Notes | Open Water Diver course requires 6 supervised dives |
| MDEA est. 1984 | |
| Stands for | Multinational Diving Educators Association |
| Contact | (615)352-8890 |
| Entry-Level Certifications | Level One Diver |
| Open-water-dives required | NA |
| Pool-water-dives required | NA |
| Lecture hours required | NA |
| Notes | - |
| NASE est. 1982 | |
| Stands for | National Academy of Scuba Educators |
| Contact | (904)264-4104 www.nasescuba.com |
| Entry-Level Certifications | Open Water Diver |
| Open-water-dives required | 4 |
| Pool-water-dives required | 5 |
| Lecture hours required | 5 |
| Notes | Instructors and students have the option of home study |
| NASDS est. 1961 | |
| Stands for | National Association of Scuba Diving Schools |
| Contact | (901) 767-7265 www.divesafe.com |
| Entry-Level Certifications | Open Water Diver |
| Open-water-dives required | 4 |
| Pool-water-dives required | 10 modules, 60 to 90 minutes each |
| Lecture hours required | 10 modules, 60 to 90 minutes each |
| Notes | - |
| NAUI est. 1960 | |
| Stands for | National Association of Underwater Instructors |
| Contact | (800)553-6284 www.naui.org |
| Entry-Level Certifications | Scuba Diver |
| Open-water-dives required | 4 scuba, 1 skin |
| Pool-water-dives required | 10 hours total in pool and open water |
| Lecture hours required | Estimated 14 hours |
| Notes | Nonprofit organization |
| PADI est. 1966 | |
| Stands for | Professional Association of Diving Instructors |
| Contact | (800)729-7234 www.padi.com |
| Entry-Level Certifications | PADI Open Water Diver |
| Open-water-dives required | 4 |
| Pool-water-dives required | 5 modules |
| Lecture hours required | 5 modules |
| Notes | All modules are performance-based requiring no set time limits |
| PDIC Int'l est. 1975 | |
| Stands for | Professional Diving Instructors Corporation |
| Contact | (717)342-1480 www.pdic-intl.com |
| Entry-Level Certifications | Open Water |
| Open-water-dives required | 4 scuba, 1 skin |
| Pool-water-dives required | Minimum of 6 |
| Lecture hours required | Minimum of 6 |
| Notes | - |
| SSI est. 1970 | |
| Stands for | Scuba Schools International |
| Contact | (800)892-2702 www.ssiusa.com |
| Entry-Level Certifications | Open Water Diver |
| Open-water-dives required | 5 scuba, 1 skin recommended |
| Pool-water-dives required | 6 |
| Lecture hours required | 6 |
| Notes | Total course hours recommended is 16 to 32, depending on whether a home study or classroom situation |
| YMCA Scuba est. 1959 | |
| Stands for | Young Men's Christian Association |
| Contact | (770)662-5172 www.ymcascuba.com |
| Entry-Level Certifications | Open Water SCUBA Diver |
| Open-water-dives required | 4 scuba, 1 skin |
| Pool-water-dives required | 12 |
| Lecture hours required | Approximately 12 |
| Notes | Pool and lecture must total 24 hours, at least half of which must be in the pool. Nonprofit organization |
| WASI est. 1997 | |
| Stands for | World Association of Scuba Instructors |
| Contact | (801) 363-9274 www.divewasi.com |
| Entry-Level Certifications | Open Water Diver |
| Open-water-dives required | 4 |
| Pool-water-dives required | Minimum of 4 |
| Lecture hours required | 4 units, time required up to instructor |
| Notes | Introductory DAN membership included with certification |