Over the years, technological advances have made scuba diving a safer sport. A wide variety of products on the market allow you to increase how safe you are in the water. Ultimately, the goal of safety gear is to never be needed. If you ever find yourself in an emergency situation, the last thing you want to do is wind up thinking, "If I only had a ____!"
Dive flags come in a variety of shapes and sizes, and they allow people to know where you are when you're at depth or when snorkeling at the surface. They alert boaters to the fact that divers are in the area and should use care. The last thing you want to do is surface in the path of an oncoming boat; use a flag to alert boat captains that you are on your way to the surface so they can adjust their navigation accordingly.
One style of dive flag remains at the surface and are kept in position by a flotation device (much like a small inner tube or pool float) or a buoy. Another kind of dive flag attaches to your snorkel, which is ideal for divers and snorkelers who are surface swimming.
If you find yourself in a search/rescue situation, water dye allows searchers to locate you more easily, which saves all-important time.
When the dye is deployed during a daytime rescue, a yellow or red "slick" is created around the diver/ snorkeler. This slick increases the person's visibility and allows divers to locate him/her that much faster. If your rescuer is in a helicopter, the person in the helicopter is much more likely to see dyed water than a person bobbing in the water.
In cold water, hypothermia is a very real risk; by using water dye to reduce the amount of time it may take for rescuers to locate you, you are increasing your chances of avoiding hypothermia.
Having a whistle attached to your BCD can be a lifesaving tool should you need to be located by rescuers or to gain the attention of the people on your dive boat. Emergency whistles require less energy than does screaming or yelling; in addition, the sound created by whistles is more far reaching than is the human voice.
If you find yourself in an emergency situation while underwater and you need to get your buddy's, an underwater horn/signaling device can alert your buddy to the fact you need him/her. Underwater horns at- tach between your 1st stage and your air hose; by pressing a button on the horn, a sound that is audible underwater is emitted. Unless they're wearing full-face masks with communication devices, divers cannot talk while at depth. Underwater signaling devices allow divers to get the attention of others when they are in need of help. They are also a convenient way to alert your buddy if she/he is outside the sound range of your tang banger.
Underwater horns can also be used at the surface, should a diver need help but cannot use his/her voice and does not have a whistle.
If you are in a situation in which you need/want your dive buddy's attention, but the situation isn't dire, a tank banger can be used to alert your buddy. Tank bangers are circular rubber tubing that is threaded through a plastic bead. This tubing is placed around the base of your tank, with the bead in a position that is easily reached by the diver. When you need to gain your buddy's attention, simply grab the bead with an outward motion and then release the bead. The bead will create a reverberating sound, which can be heard by your nearby buddy.