Navigating safely: Many people who die by drowning die in navigation accidents. Safe navigation practices include being informed of the state of the sea and equipping the boat with regulatory instruments to keep people afloat. These instruments are lifejackets (see lifejacket use above) and professional lifebuoys with the shape of a circle  (ring-buoy, hoop-buoy, life-ring, life-donut, lifesaver, or life preserver). Use the "buddy system": Dont swim alone, but with another person who can help in case of a problem. Rescue robots and drones: Nowadays, there exist some remote-controlled modern devices that can accomplish a water rescue. Floating rescue robots can move across the water, allowing the victim to hold on to the drone and be moved out of the water. Flying drones are very fast and can drop life jackets from air, and may help to locate the victim’s position. Follow the rules: Many people who drown fail follow the safety guidelines of the area. It is important to pay attention to the signage that indicates whether swimming is allowed or if a lifeguard is on duty. (lifeguards, coastguards, etc.) Water safety
The concept of water safety involves the procedures and policies that are directed to prevent people from drowning or from becoming injured in water. Time limits
The time a person can safely stay underwater depends on many factors, including energy consumption, number of prior breaths, physical condition and age. An average person can last between one and three minutes before falling unconscious, and around ten minutes before dying.
Only the normal skin would react with a characteristic erythematous response. Examination under a Wood lamp can also reveal the nevus anemicus patch will not emphasize as a patch of vitiligo would. Diagnosis
Treatment
Since the histopathology of nevus anemicus is normal, nevus anemicus is a pharmacologic nevus and not an anatomic one. In most people a nevus anemicus is on a covered area and so light in appearance that no treatment is needed. See also
List of cutaneous conditions
Melanism
Nevus
Skin lesion


== References ==