Tank Factors In technical diving, executing the rule of thirds or planning gas management is simple when everyone on the team swims with the exact same cylinders. If both you and your buddy carry identical doubles and start with equal pressure, you will turn the dive at the exact same pressure. However, this [...]
Helium Penalty Technical divers use helium to reduce gas density and narcosis. The "Helium Penalty" is the theoretical idea that because helium is a smaller, faster molecule than nitrogen, it requires deeper stops and longer decompression times. Modern research suggests this is theoretically incorrect. The famous shearwater article described this inaccuracy and quickly [...]
Important Gear Technical divers are usually meticulous - or, at least I hope they are. We should analyze and label every cylinder, research relevant topics, and reduce risk as much as is reasonable. Regulators should be taken care of and serviced routinely. The same goes for CCRs, lights, and exposure protection. The most important [...]
I don't want to do open circuit trimix, I'd rather get a CCR and save the money As the cost of trimix continues to rise, this conclusion continues to be more attractive. But - does the math check out? Probably not. Open circuit trimix still has a place in diving and is the correct [...]
Oxygen Toxicity Most divers know the NOAA Central Nervous System (CNS) oxygen exposure chart and the CNS tracker on your computer — telling you how long you can stay at a given partial pressure of oxygen. It’s a useful tool, but like most tables, it only tells part of the story. Oxygen toxicity [...]
CCR Skills This text is a supplement to your CCR training. We will review all of these procedures together, and all skills will be demoed by me. Reading about the skills beforehand is a great way to prepare for your class. CCR diving requires a lot of new concepts and procedures. Take notes and [...]
Gag Straps and CCRs Are Mouthpiece Retaining Straps (MRS)—sometimes called gag straps—a good idea?For recreational rebreather divers, the answer is likely no. More evidence could change my opinion here, but at present, any recommendation for MRS use is weak. This topic was discussed at Rebreather Forum 4 (RF4), where [...]
Bonaire Tek Week 2025 I attended the 2025 Bonaire Tek Week at Buddy Dive Resort. It was my first time in Bonaire. I taught a class for a few days and did some fun diving the other days. Here is a synopsis of what to expect when traveling to [...]
CCR Calibration This article is a refresher for certified CCR divers. This does not replace manufacturer recommendations, formal training, or time with an instructor. If you're confused about any of these aspects, contact your instructor and schedule a refresher. This article is specific to the O2tima CM unit. Other units are different. When [...]
CO₂ Scrubber Use in the O₂ptima CM CCR Disclaimer: This article is a refresher for certified CCR divers. It does not replace manufacturer recommendations, formal training, or time with an instructor. If you are unclear on any points here, contact your instructor and schedule a refresher. This information is specific to the O₂ptima CM [...]
