Freediving, free-diving, free diving, breath-hold diving, or skin diving, is a mode of underwater diving that relies on breath-holding until resurfacing rather than the use of breathing apparatus such as scuba gear.
A diving suit is a garment or device designed to protect a diver from the underwater environment. A diving suit may also incorporate a breathing gas supply, but in most cases the term applies only to the environmental protective covering worn by the diver. The breathing gas supply is usually referred to separately. There is no generic term for the combination of suit and breathing apparatus alone. It is generally referred to as diving equipment or dive gear along with any other equipment necessary for the dive.
Professional diving is underwater diving where the divers are paid for their work. Occupational diving has a similar meaning and applications. The procedures are often regulated by legislation and codes of practice as it is an inherently hazardous occupation and the diver works as a member of a team. Due to the dangerous nature of some professional diving operations, specialized equipment such as an on-site hyperbaric chamber and diver-to-surface communication system is often required by law, and the mode of diving for some applications may be regulated.
Joseph Augustus Zarelli, previously known as the "Boy in the Box", "Boy in a Box" or "America's Unknown Child", was an American 4-year-old male whose nude, malnourished, beaten body was found on the side of Susquehanna Road, in Philadelphia, Pennsylvania, on February 25, 1957. Joseph appeared to have been cleaned and freshly groomed, with a recent haircut and trimmed fingernails, although he had suffered extensive physical attacks prior to his death, with multiple bruises on his body. He was also severely malnourished. His body was covered with scars, some of which were surgical. Authorities believe that the cause of death was homicide by blunt force trauma.
The Doe Network is a non-profit organization of volunteers who work with law enforcement to connect missing persons cases with John/Jane Doe cases. They maintain a website about cold cases and unidentified persons, and work to match these with missing persons.
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done.
Maura Murray is an American woman who disappeared on the evening of February 9, 2004, after a car crash on Route 112 near Woodsville, New Hampshire, a village in the town of Haverhill. Her whereabouts remain unknown. Murray was a 21-year-old nursing student completing her junior year at the University of Massachusetts Amherst at the time of her disappearance.
Ear clearing, clearing the ears or equalization is any of various maneuvers to equalize the pressure in the middle ear with the outside pressure, by letting air enter along the Eustachian tubes, as this does not always happen automatically when the pressure in the middle ear is lower than the outside pressure. This need can arise in scuba diving, freediving/spearfishing, skydiving, fast descent in an aircraft, fast descent in a mine cage, and being put into pressure in a caisson or similar internally pressurised enclosure, or sometimes even simply travelling at fast speeds in an automobile.
Tara Faye Grinstead was an American high school history teacher from Ocilla, Georgia, who went missing on October 22, 2005, and was declared dead in 2010.
Recreational dive sites are specific places that recreational scuba divers go to enjoy the underwater environment or for training purposes. They include technical diving sites beyond the range generally accepted for recreational diving. In this context all diving done for recreational purposes is included. Professional diving tends to be done where the job is, and with the exception of diver training and leading groups of recreational divers, does not generally occur at specific sites chosen for their easy access, pleasant conditions or interesting features.
Human factors are the physical or cognitive properties of individuals, or social behavior which is specific to humans, and which influence functioning of technological systems as well as human-environment equilibria. The safety of underwater diving operations can be improved by reducing the frequency of human error and the consequences when it does occur. Human error can be defined as an individual's deviation from acceptable or desirable practice which culminates in undesirable or unexpected results. Human factors include both the non-technical skills that enhance safety and the non-technical factors that contribute to undesirable incidents that put the diver at risk.
[Safety is] An active, adaptive process which involves making sense of the task in the context of the environment to successfully achieve explicit and implied goals, with the expectation that no harm or damage will occur. – G. Lock, 2022
Dive safety is primarily a function of four factors: the environment, equipment, individual diver performance and dive team performance. The water is a harsh and alien environment which can impose severe physical and psychological stress on a diver. The remaining factors must be controlled and coordinated so the diver can overcome the stresses imposed by the underwater environment and work safely. Diving equipment is crucial because it provides life support to the diver, but the majority of dive accidents are caused by individual diver panic and an associated degradation of the individual diver's performance. – M.A. Blumenberg, 1996
Diver training is the set of processes through which a person learns the necessary and desirable skills to safely dive underwater within the scope of the diver training standard relevant to the specific training programme. Most diver training follows procedures and schedules laid down in the associated training standard, in a formal training programme, and includes relevant foundational knowledge of the underlying theory, including some basic physics, physiology and environmental information, practical skills training in the selection and safe use of the associated equipment in the specified underwater environment, and assessment of the required skills and knowledge deemed necessary by the certification agency to allow the newly certified diver to dive within the specified range of conditions at an acceptable level of risk. Recognition of prior learning is allowed in some training standards.
The Texas Killing Fields is a title used to roughly denote the area surrounding the Interstate Highway 45 corridor southeast of Houston, where since the early 1970s, more than 30 bodies have been found, and specifically to a 25-acre patch of land in League City, Texas where four women were found between 1983 and 1991. The bodies along the corridor were mainly of girls or young women. Furthermore, many additional young girls have disappeared from this area who are still missing. Most of the victims were aged between 12 and 25 years. Some shared similar physical features, such as similar hairstyles.
Amy Marie Yeary was an American woman whose body was discovered on November 23, 2008, near Campbellsport, Fond du Lac County, Wisconsin. Her body remained unidentified for 13 years before investigators announced her identification via forensic genealogy and dental records on November 23, 2021.
Tammy Corrine Terrell was an American murder victim from Roswell, New Mexico. Her body was discovered on October 5, 1980, in Henderson, Nevada, and remained unidentified until December 2021. Her case has been the subject of extensive efforts by investigators and has been highlighted as inspiring other work to solve cold cases of unidentified murder victims.
Unidentified decedent, or unidentified person, is a corpse of a person whose identity cannot be established by police and medical examiners. In many cases, it is several years before the identities of some UIDs are found, while in some cases, they are never identified. A UID may remain unidentified due to lack of evidence as well as absence of personal identification such as a driver's license. Where the remains have deteriorated or been mutilated to the point that the body is not easily recognized, a UID's face may be reconstructed to show what they had looked like before death. UIDs are often referred to by the placeholder names "John Doe" or "Jane Doe". In a database maintained by the Ontario Provincial Police, 371 unidentified decedents were found between 1964 and 2015.
Ann Heron was a British woman who was murdered on 3 August 1990 at her home in Darlington, County Durham, by an unidentified killer. The case was heavily featured in British media as well as on the BBC programme Crimewatch in October 1990, but her murder remains unsolved.
Erin Foster and Jeremy Bechtel were two American teenagers from Sparta, Tennessee, who disappeared in April 2000. Their remains were eventually found in Foster's submerged vehicle in the Calfkiller River in 2021 by Jeremy Sides, a volunteer civilian cold-case investigator and YouTuber.
Jeremy Beau Sides, aka "Nug" from the YouTube channel Exploring with Nug, is an American scuba diver and civilian crime investigator who investigates missing person cases and missing items. In 2021, he found the bodies of Erin Foster and Jeremy Bechtel, who had been missing for 21 years.
