Tips on dive light use and etiquette • Part Two
Dive lights are as essential as masks, fins, tanks and regulators. This is the second of two articles designed to help you get the most from your dive lights.
Take a light with you on every dive
There are many reasons for this; however, chief among them is that a dive light can serve as an emergency signaling device, both above and below water.
- Above water, a dive light may be the most effective way to let a dive boat know where you are.
- Underwater, you can communicate with your buddies using any of a variety of signals.
Your light must have a strobe function to be an effective emergency signaling device. When in strobe mode, dive lights are as much as 80 percent more noticeable than they would be otherwise. This is why the FAA requires aircraft to have strobe lights; doing so helps prevent collisions. If separated from your dive boat, wouldn’t you want to be 80 percent more likely to be seen?
Underwater communication
In daylight, divers can communicate underwater using any of a variety of hand signals. This is hard to do at night. Fortunately, several standard light signals can be used to convey essential information. These include:
- Attention: Move your light back and forth slowly in any direction. If your buddy isn’t facing you, shine your light on the same spot your buddy’s light is illuminating; this is where they are looking. This will be more effective if your light has a tightly focused beam. Once you have a buddy’s attention, you can shine your light on your hand to communicate with standard hand signals.
- Emergency: This is the same as the Attention signal except that you move the light back and forth rapidly. It tells others you need immediate assistance.
- Okay: Move your light in a circular motion. You can do this to both ask if a buddy is okay or to respond to a buddy who is asking if you are okay. If you are not, use a combination of light and hand signals to explain why.
“Watch where you point that thing!”
Today’s LED dive lights are significantly brighter than their predecessors. While this lets us see more, it can also cause problems. You must take care to not shine your light in another diver’s eyes.
Blinding another diver can cause a host of problems. It can:
- Disorient your buddies making it harder for them to maintain buoyancy and direction.
- Diminish their night vision.
- Trigger an aggressive response in some divers.
- Induce panic and fear.
Your light can have a similarly detrimental effect on aquatic life. It can interfere with an animal’s ability to defend itself. A light-blinded animal can also swim into coral or other objects, injuring itself.
Above all, do not shine your light directly at your dive boat. The last people you want to blind are the crew that keeps you safe.
Pre-dive check
Your dive light deserves the same level of attention you give all your equipment before any dive. Things to check include:
- Is the light fully charged? (Check this before leaving for the dive site.)
- Are plugs, caps or anything else that ensures the light’s watertight integrity firmly in place?
- Does the switch work as it should?
- Is the light firmly secured to the back of your hand, your wrists or a harness D-ring before you enter the water?
These steps help ensure your light is not lost or damaged.
Enjoy the Darkness
Dive lights have come a very long way since their inception. Despite what you may have heard, turning your light off and on while underwater is perfectly acceptable. Don’t be afraid to do so.
We have seen some of the most wonderful things on a night dive when our lights were off. Try it sometime. Allow your eyes to adjust to the darkness and enjoy what you will see around you.