Snorkeling
The use of this equipment allows the snorkeler to observe the underwater environment for extended periods with relatively little effort, and to breathe while face-down at the surface.
It provides the opportunity to observe underwater life in a natural setting without the complicated equipment and training required for scuba diving.
Environmental protection against cold, sunburn, and marine stings and scratches is also regionally popular, and may be in the form of a wetsuit, dry suit, dive skins, or rash vest.
A snorkel is a device used for breathing air from above the surface when the wearer's head is facing downwards in the water with the mouth and the nose submerged.
A swimmer's snorkel is a tube bent into a shape often resembling the letter "L" or "J", fitted with a mouthpiece at the lower end and constructed of light metal, rubber or plastic.
An integrated snorkel consists essentially of a tube topped with a shut-off valve and opening at the bottom into the interior of a diving mask.
That ease of access may result in more snorkelers who lack experience or have underlying medical conditions, possibly exacerbating problems that are unrelated to the type of equipment being used.
[9][10][11] Italian healthcare legislation requires patients to sign a declaration of acceptance of use of an uncertified biomedical device when they are given the modified snorkel mask for respiratory support interventions in the country's hospitals.
All scuba diving masks consist of the lenses also known as a faceplate, a soft rubber skirt, which encloses the nose and seals against the face, and a head strap to hold it in place.
These range from oval shaped models to lower internal volume masks and may be made from different materials; common choices are silicone and rubber.
Open-backed fins allow the wearer to wear them over the top of wetsuit socks or boots which can be useful in cooler water.
Wetsuit protection can be extended to cover the head, feet and hands with the addition of a hood, gloves, socks or boots.
[17] In the new millennium, the use of drysuits in snorkelling is seeing something of a resurgence, thanks to the growing popularity of "wilderness swimming" or "wildswimming" in seas, lakes and rivers.
A rash guard by itself is used for light coverage in warm to extreme summer temperatures for several watersports including snorkeling.
This involves a sharp puff in the early stage of exhalation, which is effective for clearing the tube of remaining water, and a fairly large but comfortable exhaled volume, mostly fairly slowly for low work of breathing, followed by an immediate slow inhalation, which reduces entrapment of any residual water, to a comfortable but relatively large inhaled volume, repeated without delay.
Elastic recoil is used to assist with the initial puff, which can be made sharper by controlling the start of exhalation with the tongue.
[26] Modern designs use silicone rubber in the mouthpiece and one-way clearing and float valves due to its resistance to degradation and its long service life.
In even older designs, some snorkels were made with small "ping pong" balls in a cage mounted to the open end of the tube to prevent water ingress.
Usage of the term "snorkel" in this section excludes devices integrated with, and opening into, swimmers' or divers' masks.
The total length, inner diameter and/or inner volume of a snorkel tube are matters of utmost importance because they affect the user's ability to breathe normally while swimming or floating head downwards on the surface of the water.
A high-volume tube is liable to encourage a build-up of stale air, including exhaled carbon dioxide, because it constitutes respiratory dead space.
This mass of documentation has enormous scientific potential, as millions of tourists are able to cover greater areas than professional scientists whose field-study time is limited.
[citation needed] The greatest danger to snorkelers are inshore and leisure craft such as jet skis, speed boats and the like.
Snorkelers may therefore choose to wear bright or highly reflective colors/outfits and/or to tow dive flags on floats to enable easy spotting by boaters and others.
[citation needed] Snorkelers' backs, ankles, and rear of their thighs can be exposed to the sun for extended periods, and can burn badly (even if slightly submerged), without being noticed in time.
Wearing appropriate covering such as a "rash guard" with SPF (in warmer waters), a T-shirt, a wetsuit, and especially "waterproof" sunblock will mitigate this risk.
Booties and surf shoes are especially useful as they allow trekking over reefs exposed by low tide, to access drop-offs or deeper waters of the outer reef—practices which are, however, considered ecologically irresponsible.
Some creatures, like moray eels, can hide in coral crevices and holes and may bite fingers in response to prodding.
Enough water cover to swim over the top without kicking the bottom is needed, but isolated shallow structure can be approached from the sides.
Deeper reefs can also be explored, but repeated breath-holding to dive to those depths limits the number of practitioners, and raises the bar on the required fitness and skill level.
