Indispensable diving experience - night diving skills and precautions

For people who have never dive or haven't even been in contact with the dive, it is hard to imagine how to perform diving at night. But for divers who like night diving activities, the charm of night diving is quite fascinating! The underwater scenery at night is definitely not lost during the day!

Night underwater world

When the night comes, when the biological activity in the water changes, the common creatures in the daytime will hide in their nests and replace them. Instead, creatures accustomed to activities at night will begin to appear. This is the most attractive aspect of night diving - you can see a very different biological phase from the day.

In the evening, we find it difficult to see large-scale fish. Apart from the biological habits of the creatures, and because visibility at night is limited by the range of light irradiation, we can hardly detect large fish in the distance; The focus of observations is on macroscopic organisms that can be observed at close range. The most common ones are all kinds of bizarre shrimps and crabs, and octopuses and other creatures are easily found at night.

How to perform night diving activities

To participate in night diving, it is recommended that you should participate in night training in advanced courses, because there are many skills that require special attention when performing night diving. Most of them are related to safety, and only complete night training is required. Learn how to safely perform night diving activities.

Normal night diving activities are scheduled for the last dive on the day. Participants must measure in advance whether their physical conditions are sufficient. In addition, if they are in an unfamiliar dive environment, unless there is a guided leader who is familiar with the dive site, At least one dive should be performed at this point during the day.

When personal equipment is assembled, it is best to carry it out in a well-lighted place. Otherwise, it will be easy to make mistakes in assembling the equipment and affect the diving activities.

After entering the water, you should strictly observe the system of potential companions and must not be separated from the diving team. During the spring and autumn seasons, after night diving, you should pay attention to keeping warm measures and avoid catching cold.

Night diving activities necessary equipment and skills

1 Lighting source

Commonly used light sources are divided into main lights, auxiliary lights, and indicator lights. The main light is usually a submersible lamp with a long wattage and a long voyage. It is sufficient to maintain the lighting of a dive. The battery used has two types of special rechargeable batteries or dry batteries. The concept of using a rechargeable battery is more environmentally friendly, but it requires Considering the problem and time of charging, using dry batteries has the advantage of being easy to obtain.

The secondary lights are also known as BC lights, which are usually in the form of batteries that are smaller and can be stored in BC pockets. The main purpose is to provide a backup light source in case the main light fails in water to ensure safety. Also, if you need to explore the caverns or the dark places during daytime diving, you can always use them to provide lighting.

The indicator light is usually small and can be tied to the BC or the cylinder head. The function is to indicate the position of the diver.

In terms of standard safety regulations, each night diving activity must be prepared by one person for each of the main and auxiliary lights, and calculated in units of two-person potential companions. If one of the main lights fails to use the standby light, diving can continue. If both lights are inactive, diving must be stopped and the direction of the return trip is advanced. You must not fall into the condition of two people but only one dive light. Such a situation will inevitably increase the chance of danger.

2 navigation capabilities

The use of compass navigation during night dives will be much more frequent than natural navigation, so divers should be skilled in compass navigation. Before entering the water, the directions of water entering and exiting shall be declared and recorded on the north compass, so that each diver has a basis for navigation. Also, in and out of the water, you should first look for a bright and obvious object, such as a street lamp on the seashore, or the lights of a seashore merchant. Such a target can quickly find the landing point when the water is discharged.

3 Left-behind people

The difficulty of entering and leaving the water at night is much higher than during the day. If someone who is not in the same person participates in the night dives, it is recommended that the member be able to serve as a left-behind person on the shore, not only to take care of the items left on the shore, but also to assist the divers to access. water. If there is an urgent need, contact related personnel. Therefore, the left-behind people on the shore can also be considered as an important part of night diving safety.

4 Photography Equipment

Photographs at night can easily create an eye-catching effect because the dark background can make the subject even more prominent.

Here are some notes about night dive

1 Stay in shallow water and stay in close contact

Night diving is often in shallow water, so you can have enough time to slowly advance and enjoy it all. The colors of the water at night are more vivid and pleasant than during the day. They are very beautiful. In fact, this is a simple diving physics. If you dive at a depth of 20 meters during the day, the sunlight is absorbed by the water and the color has been tampered with. Diving at night, your light source can never exceed 3 meters, so the water retains the original look of light.

2 Redefining "Night"

When the sun is low in the air, the light that can penetrate the water is very limited. Even if there is a certain light source on the water, the underwater is still dark. Evening dives are a good way to begin night dive. The reef creatures migrate and the animals in the daytime activities hide. The nighttime creatures start to pour out and come out to feel a bit of a handover.

3 Bring the right equipment

You need to bring two dive lights, one is necessary and the other is spare. The main light should be relatively large and bright enough. As for how big and bright? Depending on the clarity of the water, the choice of lamp may vary. When purchasing a dive light, there are gaps between some fixtures and handles. Try several times and find the best light that meets your personal preference. The spare light is a bit smaller, but the brightness is also enough to help you find the way back. Usually the spare lamp is smaller and more like a traditional flashlight. However, it is important to remember that if the main light fails, the standby light should be activated immediately and the dive should end.

4 Fasten the dive lights

Most dive lights are accompanied by a lanyard or wrist strap, and they are all one by one. If the dive lights fall out, it is terrible to be underwater. Most of the dive lights have negative buoyancy. If you accidentally drop the lights into the deep sea, it is impossible to find them again.

5 Awareness of signals

Night Dive Due to the limitation of visibility, some underwater gestures may be different from those during the day. You should confirm the gestures before buddy launches, and select which one you want to use. You have two choices: One is to use a flashlight as your hand and let your Buddy see what you want to say. The other is to use your flashlight to release the signal. Turning the circle with a flashlight means OK, shaking up and down means Yes, shaking left and right is No. You can even use your own flashlight to chase Buddy's beam to catch his attention. If you are far away from the dive boat, point the beam in the direction of the boat until you notice the crew, then use your flashlight on your head so that the crew can see where you are.

6 Use diving lights with caution

Whenever there is a night dive, be careful about the dive lights. It is like a smashed gun. You can't shoot directly into Buddy's eyes with a dive light. Doing so will ruin his night vision.

7 Operate freely

The first night dive divers tend to buy the largest and brightest dive lights. They cling to it like they grabbed a safety blanket. In fact, when you have a certain night diving experience, you will find that the smaller primary dive lights perform equally well, especially in clear waters. Sometimes night dives, light sources from Buddy, boats and the moon can provide a lot of ambient light, so you can save a lot of light energy. If you want to turn on the dive lights, you don't need to open them to the brightest. Some LEDs are set to half power and you can adjust the brightness using the callback method. One of the most unique things about night dives is bioluminescence. Some unicellular snorkeling creatures emit light when they feel uneasy underwater. Your ankles or your hand wave can cause the "sparks" on the sea to open, but in the dark environment of the sea, you will miss some wonderful pictures.

8 Precaution

Before you perform your first night dive, you should dive first during the day. Be familiar with the layout of this dive site and adapt it.

9 Return mark

If you are getting water from the shore instead of from the boat, you should place lights on the beach. It is best to put two lights near the entrance/exit point, and the other light is a little bit farther. These can be a sign of your return after diving. Use strobe lights on the boat so that you can return smoothly. When you are near the boat, take a close look and see the water to avoid hitting the hull.

10 Have fun

The most important point is to relax and enjoy diving. Before you step into a dark ocean or lake, feeling nervous is a person's instinctive response, but it comes with stimulation. When you overcome your anxiety about night diving, you will get a precious experience and leave a new and lasting dive memory.