Announcing the 2025 NAUI International Technical Diving Summit Speakers
NAUI Worldwide proudly invites the global diving community to the 2025 NAUI International Technical Diving Summit (NITDS), a premier gathering of elite technical diving professionals, educators, and explorers. Taking place October 31 – November 8, 2025, in Florida’s legendary cave country, this summit offers an unmatched opportunity to advance your technical diving knowledge, engage with some of the most respected instructors in the industry, and experience the crystal-clear freshwater cave systems that make Florida a world-renowned diving destination. We are proud to announce our esteemed Technical Talks speaker lineup below:
For more information and to register for any of the NIDTS events, visit the FareHarbor Registration or scan the QR code:
Dr. Frauke Tillmans
DAN Research Director
Dr. Frauke Tillmans is a leading voice in diving science and safety, bringing a strong background in neuroscience and human biology to the global diving community. She earned her PhD in Human Biology from the University of Ulm, Germany, and has dedicated her career to advancing research in diving injury and fatality monitoring, population health, and diving physiology — from acute injuries to the long-term effects of extreme environments.
An accomplished diver, safety officer, and instructor, Dr. Tillmans’ experience spans recreational, technical, rebreather, scientific, and public safety diving. Her career has included extensive work with recreational, professional, and military divers, first at the German Naval Medical Institute and now in the United States. Since 2019, she has served as the scientific leader at Divers Alert Network (DAN), where she manages global research collaborations, oversees DAN’s grant program, and directs its STEM-focused internship program, inspiring the next generation of diving and hyperbaric medicine professionals.
Dr. Tillmans also holds academic roles as an adjunct assistant professor in Biomedical Engineering at the University of North Carolina at Chapel Hill and as a visiting scientist at the University of California, San Diego. Her work continues to bridge science, safety, and education, shaping the future of diving medicine worldwide.
Dr. David Charash
Dive Medicine Physician
Dr. David Charash has dedicated more than three decades to advancing the health and safety of the diving community. Board Certified in both Emergency Medicine and Undersea and Hyperbaric Medicine, he is a practicing Dive Medicine Physician who has developed and led workshops, seminars, and international symposiums on dive medicine, safety, and technology.
Dr. Charash is a Divers Alert Network (DAN) Referral Physician, DAN Instructor, and volunteer researcher, and his expertise has been sought by institutions including the Naval Undersea Medical Institute, the United States Navy, and the U.S. Coast Guard Academy. As a consultant, he has supported expeditions in some of the world’s most remote environments, ensuring diver safety in challenging conditions.
He also shares his passion through media, serving as host of the Fitness in Diving podcast, available on Apple and Spotify. His contributions to the field have been recognized with some of diving’s most prestigious honors, including the 2022 DAN/Rolex Diver of the Year and 2025 Diver of the Year in Sciences awarded by Beneath the Sea.
Ken Charlesworth
NAUI Technical Instructor Examiner
Ken Charlesworth, NAUI Technical Instructor Examiner, has spent decades exploring the world’s wrecks and caves with a passion for underwater history. An avid wreck diver since 1977, he expanded his training into cave diving in 1996 and, after relocating to Florida in 2003, has continued diving the state’s caves and wrecks on a weekly basis.
His lifelong interest in World War II shipwrecks has driven extensive exploration of Florida’s coast, home to the largest concentration of WWII wrecks in the region. Of the 41 vessels attacked by German forces, 28 were sunk, with 12 resting in waters shallower than 240 feet. Seven of these historic wrecks can be found within a 36-mile boat ride of Port Canaveral, where Ken continues to pursue his passion for discovery, preservation, and technical diving education.
Andrew Pitkin
Cave Explorer & Anesthesiologist
Andrew Pitkin brings more than three decades of experience in diving, medicine, and exploration to the technical diving community. He learned to dive in 1992 in the cold, murky waters of the United Kingdom and soon expanded into cave and technical diving by 1994.
From 1996 to 2000, he worked at the Royal Navy’s Institute of Naval Medicine, where he managed a hyperbaric facility, treated decompression illness, and contributed to research on submarine escape, diver health outcomes, and the testing of advanced military underwater breathing systems.
Since moving to Florida in 2007, Andrew has been a faculty member at the University of Florida College of Medicine in Gainesville while continuing to participate in numerous underwater cave exploration and filming projects. His combined expertise in hyperbaric medicine, anesthesiology, and engineering has driven the development of innovative tools for technical cave diving, including custom rebreathers, suit heater controllers, improved DPV battery systems, heads-up displays, single-wire telephones, and underwater radiolocation devices.
A dedicated explorer, Andrew counts Weeki Wachee Spring, Mill Creek Sink, and Phantom Spring among his favorite cave diving sites, where his passion for exploration and innovation continues to push the boundaries of what is possible underwater.
Anders Estander
Technical Instructor
Anders Etander is a passionate technical diver and instructor from Sweden whose career has been shaped by a love for mine and cave exploration. His journey began 13 years ago with his first dive in the open sections of the Tuna Hästberg mine, 80 meters underground — an experience that sparked a lifelong dedication to overhead environment diving.
In addition to training divers in mine and cave techniques, Anders actively explores abandoned mines across Sweden and contributes to the ongoing exploration of one of the country’s few water-filled mountain caves, a site accessible only during the winter months. He also serves as the head of diving operations at Tuna Hästberg and holds keyholder status for several other historic mines that remain open to divers and visitors.
Through both instruction and exploration, Anders continues to advance opportunities for divers to safely experience and understand these unique and challenging environments.
Chris Brock
With nearly two decades of diving experience, Chris brings both passion and expertise to the world of technical diver training. He began his teaching career in the lakes of Oklahoma before relocating to Florida, where he has since become a full-time instructor specializing in advanced cave, rebreather, and trimix training.
An educator at heart, Chris holds both a Bachelor’s and Master’s degree in Education, taught Chemistry and Physics for over a decade, and coached varsity athletics before fully dedicating himself to diving. Today, he serves as a NAUI Course Director, Instructor Trainer, and Technical Instructor Evaluator, as well as Training Director, Instructor Sponsor, and Instructor Evaluator for the NSS-CDS. With over 1,000 cave dives, his expertise includes rebreather instruction on the Fathom MKIII, Fathom Gemini, Optima, and Optima Chest Mount units.
Guided by his personal motto, “Excellence is earned,” Chris is committed to creating opportunities for divers to excel and achieve mastery, with every class built on a foundation of safety, precision, and excellence in technical diving.
Heison Chak
Scuba Labs
Heison is a Recreational, Technical, and CCR Instructor who has dedicated more than a decade to teaching and mentoring divers. His deep commitment to dive safety is reflected in his long-standing service to the Ontario Underwater Council (OUC), where he contributed extensively as Director of Sport Safety before being elected President in 2015.
As a NAUI Course Director and Technical Instructor Examiner, Heison works closely with NAUI Headquarters to help shape the next generation of diving leaders. His role in Leadership Conferences and the NAUI Mobile Training Team emphasizes the development of strong skills and leadership qualities in aspiring professionals, while promoting a culture of safety, excellence, and innovation throughout the diving community.
Ready to Start Training?
The NAUI International Technical Diving Summit is your opportunity to connect with world-class experts, expand your knowledge, and be part of conversations shaping the future of technical diving.
