Escape from unwelcome situations when diving at night
When water becomes murky, visibility decrease. This happens due to the presence of dense particles in the water. The degree of turbidity of the water is determined by the sight distance in the water. Low visibility is any occasion where visibility is less than 3 meters. Unlike diving in reduced daytime visibility, diving at night when visibility is low requires some extra equipment. And special methods of communication among divers must be applied.
Night diving mandatory and desirable equipment
Night diving equipment requires the provision of surface and underwater lights. Underwater primary and secondary light. Primary light is essential in night diving. While secondary light is a spare one. We usually attach the secondary light to the BC and use it in case the primary light breaks down. Staying without light during a night dive can cause a lot of stress. Find some good tips for maintaining your diving equipment here.
Carrying an underwater lamp is also mandatory for night diving. The leader and the last diver in the group should have one. But it is best for each diver to carry his own lamp. You should never separate from the group, and divers in pairs should not separate from each other.
Dive spotting and marking lights are also used, most commonly chemical light sticks. Chemical light sticks are sealed plastic tubes with a glass ampoule that is used to mark the dive-ascent ropes as well as ships and buoys. Flashlights that pulse rhythmically to give light are also very common in use.
Extra lights are used with the primary light source and can be attached to a console, mask, headband or similar.
Underwater lamps and their use in night diving
Underwater lamps must withstand increased pressure underwater. They should have a strap that ties around your hand wrist. It’s good to have a buckle to hook it to the BC. Underwater lamps with a wide, moderately bright beam of light give the best light that illuminates the wider area with gentle light. If lamps are used frequently, it is a good idea to buy one with a rechargeable battery. Underwater lamps need to be maintained frequently to provide water resistance. Make sure the rubber bands are whole and without cracks. Coat them with a thin layer of silicone grease but do not overdo it because too much silicone grease prevents good sealing.
In night diving, it is very useful to use ropes to dive in, ascent and for decompression stops. You can also use anchor rope.
Besides all the above, it is desirable to have a compass that allows us to orient ourselves underwater, diving knife, gloves, whistle.
Diving stress and how to keep it under control
To reduce stress in night diving, the good thing is to develop a diving plan which includes:
- Choosing a diving site that must match the level of training and experience of the diver. Usually, these are the places we know from day diving.
- Limit depth to 15 meters
- Determine the maximum time spent at the bottom
- Determine air consumption – one third for diving, one third for ascent and one third for emergency reserve.
- The entry-exit points should allow easy entry and a safe exit from the water when you diving at night in low visibility. Avoid rocky shores so you don’t have to climb and jump over rocks. Illuminate the path to these points as needed. If you dive from the boat, check underwater that there are no hidden dangers – rocks, reefs.
- Mark the entry-exit points on the shore with two two-point lights
- Mark the diver with light visible on all sides (flashlight)
- Avoid parts of the coast with strong waves and water currents
- Ensure a place to change your clothes (with lights)
- Determine pairs and their leaders. The leader will control the agreed maximum depth, diving direction and track the amount of air in the diving tanks.
- Before diving, check the equipment and make sure there are no fishing tools or nets in the diving area. If so, warn divers to their locations
- Wear a suitable cold-resistant diving suit
- Do not dive in bad weather or in areas of intense fishing or traffic.
- In case of losing a partner, rise a few feet from the bottom. Hold the lamp straight in front of you, and rotate around 360 degrees. If you don’t see your partner or he does not see us after 30 seconds, come to the surface and look for him. If you don’t find him, get help.
What is the proper way to dive into the water at night
Dive in at night is best done with a diving or anchor rope. Once the primary and secondary lights have been checked, we can dive in. We dive to our feet, facing our partner at the same time. Holding a BC inflator in the left hand and a rope in the right. Stay in close contact with your group or partner. If one has a problem with pressure equalization, he or she should catch the partner’s BC and thus maintain physical contact. The instruments are read by illuminating them from above, and during the dive, we take care not to dazzle the other divers with light.
How to prevent disorientation or dizziness during a night dive
During dives or ascents, disorientation and dizziness can occur. A dive into the head can cause dizziness, also if we turn upside down by peeking under the rock or reef. Disorientation can occur when you dive in too fast and if we don’t have a dive rope we should concentrate on the depth gauge and track the depth. To avoid dizziness when diving at night in low visibility, keep constant contact with your diving partner. And if you are not sure which is a direction to go up, keep track of where the air bubbles go when you exhale. During the ascent, point the light above you to see possible obstacles.
During the night dive, dive close to your partner with frequent checks to see if he or she is there. Follow your partner’s lights or tie with a brother’s rope.
Safe exit from water during night diving
Emerge gradually with safety stops no faster than 30 ft/min. The ascent rope makes easier for partners to stay together and control the moving speed. It also prevents disorientation and dizziness. The pair should face each other with the left hand on the BC inflator to control the speed of ascent. It is advisable to both hold the rope with their right hand and monitors the depth gauge. If one of the partners has a problem, the other should stay with him and catch his BC to make contact.
If there is poor visibility, it is not bad to use a fraternal rope. A rope about 2 meters long that connects two divers.
What can you do if your lights break down during night diving
In a situation when primary light fails during the night dive, you should use the secondary light to finish the dive. If there is no secondary light, try notifying your diving partner of the problem and seek his help to emerge safely. If you do not have a secondary light and your partner is not around, you will emerge on your own, carefully and safely, following the clear bubbles. Because in this situation it will be difficult to read the instruments and at the same time keep your left hand raised above your head in case there is an obstacle.
You do not have to rush if you see that the conditions for diving are difficult. Change the dive site. Diving at night when the visibility is low sometimes can scare people. Don’t be afraid of water but respect it.
Thanks for reading!