Underwater photographers sometimes refer to the narrow water zone where a subject splits the surface as the Plimsoll interface. Opportunities abound here for dynamic shots achieved by angling the camera above or below the waterline. The dedicated and creative underwater photographer can capture traditional over-under split shots with a standard straight meniscus and dramatic reflections from below of the subject, the sunlight or both as part of a modified split shot or a fully underwater picture.
The current wrapped the line around my ankle and tighten like a noose. My 30-cubic-foot safety cylinder should have provided plenty of oxygen to complete my decompression stops, but I hadn’t closed the valve after charging it, so the current rushing past the mouthpiece purged the tank. I was now trapped 20 feet beneath the surface with nothing to breathe and no one aware of my peril, hoping that my mistakes with the line and my breathing gas wouldn’t be my last.
Audible cues and signals can get your buddy’s attention, signal a group of divers or indicate a problem you can help address. Even though we may dive to escape the noise of everyday life, we need to pay attention to the sounds around us. Doing so could make your dive even more special because your buddy got your attention to see something remarkable — or you may even save a life.
After cylinders first enter service, an annual visual inspection and a five-year hydrostatic test are required. These requirements include cylinders used for diving and other life-support applications and cover breathing air, nitrox, heliox, trimix, oxygen for decompression and argon for drysuit inflation. How are these standards mandated and enforced? What are good and safe practices?
The required skills in a rescue scenario — which involved a surface swim while providing rescue breaths and removing dive gear from the victim and rescuer — were not coming easily, especially if my dive buddy was larger than me. Techniques for rescue diving seemed suited for people with a different body type and skill set — at 5 feet, 4 inches tall, I am a petite woman. Practicing rescues was challenging at best and near-impossible at worst until a course director taught me techniques and modifications that made rescuing more accessible.
It’s been more than a year since many divers have traveled internationally and visited beloved or new dive destinations. Although it is unclear when and which international destinations will be fully accessible, it’s important to stay proactive about important travel documentation preparation.
You are on the boat after a great dive when a buddy team surfaces, and one of them calls out for help. The boat crew helps get the distressed diver on board. Would you know what to do next? Whatever your level of dive training, or even if you are a nondiver dealing with an incident on land, DAN’s first aid training can help you know what to do and how to do it.
More than 100 interns over 20 years have participated in DAN’s internship programs, working with established mentors in research, risk mitigation or medicine to gain knowledge and valuable professional experience while contributing to DAN operations. This year five interns traveled to Durham, North Carolina, to participate in the program.
Where we encounter marine megafauna, we see only a tiny slice of their habitats and lives, which rarely includes feeding. These animals may travel thousands of feet vertically or migrate a few thousand miles horizontally to meet their nutritional needs. Some of them — sperm whales, for example — must do both: descend to depths of up to a mile or more to feast on aggregations of squid and roam across large swaths of the Pacific to avoid depleting their food resources in any one area.