by Dr. Thomas Powell:
Modern dive teams operate within a world inundated with technological advances. In years past, teams relied on experience, skill, and hard work. Teams today still maintain those attributes, but they also have capabilities and support structures that far exceed dive teams of the past. Technology can eliminate some of the busy work, frustration, and extensive hands-on searching that divers were once required to perform.
One of the first technologies to help dive teams around the United States was sonar. Side-scan and down-scan sonars allow dive teams to view bottom topography and look for abnormalities despite black water, currents, or short-staffed teams. Essentially, a boat operator can work with a sonar operator to cover large areas quickly when a team is searching for an object with known dimensions. As a comparison, dive teams of the past may have looked all day in a brown-water lake for a stolen vehicle that was submerged; whereas today, with the right technological assistance, a dive team can cover the same search area in a fraction of the time. This technology also provides increased safety because divers may only enter the water when a target or potential search item is located. This scenario suggests that fewer divers would be needed and the potential dive time for the associated team could be reduced. When fewer people are in hazardous water for a shorter period, the likelihood for problematic instances is reduced. The hazard reduction is further amplified when a team takes into consideration the fact that active divers will be fresh and ready to enter the water as needed.
A second technology that is still fairly new for dive teams is dive computers. Dive computers allow dive team members to record critical data such as depth, dive time, and temperature. These data sets are things that recreational divers may take for granted, but could help provide critical information to a criminal investigator or medical examiner. Though dive computers have been around for many years, technological innovation has allowed basic computer systems to record more information and support the use of various gas mixtures for divers. In a world where dive team missions grow more complicated and public safety work environments may remain unknown or unsafe, the more information available to dive teams the better. Similarly, backup digital recorders have been developed and are available to teams as redundant data recording devices. In court rooms, the concern is that a standard dive computer may have been manipulated or altered. These simple data recorders are clipped onto a diver during an operational dive and can be handed off to investigators to ensure redundant data sets and unaltered evidence sources for courtroom proceedings. The use of both dive computers and redundant data recorders can also allow a dive team to record information about a dive site to be better prepared for potential future operations in the same location.
Third, dive teams everywhere have started to use subsurface electronic communications systems. These systems may be hardwired or wireless, but in both cases the objective is to allow a diver to actually speak to surface personnel. Many of these systems even allow for digital recording capabilities. Essentially, a diver can speak in detail about what he or she finds, and how to proceed with a dive. Team leaders and tenders can also provide complex direction to a diver if issues arise or mission changes develop. Rather than relying solely on line-pull techniques, many dive teams use electronic systems for primary communication and train to use line-pulls as a redundant back-up source. The concern is that teams must still train to use line-pull communication methods and then practice these methods. Reliance on electronic systems can lead to failure if the “tried and true” older methods are not maintained.
Fourth, teams can make use of location recording devices. Global positioning systems (GPS) allow dive teams and investigators to record dive site locations, entry locations, and in some cases even evidence recovery locations. Systems such as handheld GPS units or boat-mounted GPS units can allow a location recording to be taken directly over an evidentiary collection point. Similarly, systems such as rangefinders allow shore personnel to take distance measurements from known entry locations to collection points or marker buoys. Simple rangefinder applications are even available for modern smart phones. Other smart phone applications can allow tenders or team members to take digital compass headings that can be imprinted over digital pictures to show important location information and how it visually associates with an operational dive area. These systems all allow a dive team to better record its actions and how operations were performed in relation to a dive site. Information such as this can allow a scene to be recreated and show credible proof that items were recovered from areas claimed by dive team members.
Next, modern dive teams often make use of metal detecting systems. These systems may be mounted on watercraft or carried by individual divers. Metal detectors allow a dive team to find and recover items made of various types of metals submerged underwater. A single diver may use a hand-held metal detector to find a small piece of evidence such as a handgun, or a boat mounted detection system may be able to locate larger items such as a submerged vehicle or watercraft. Again, items of this type can reduce search times and allow for more rapid and less problematic recoveries.
Finally, imaging and lighting systems are critical for dive teams. Pictures and video allow dive teams to show where items were found, the environment around these items, and the manner in which these items were recovered. With advances in small digital imaging devices, dive teams can now mount cameras to full-face mask units or other gear components. An entire dive operation can be filmed using a “hands-free” technique. Imaging evidence of this type can prove in a court room that a dive team followed proper procedure, and that items were recovered in locations claimed by dive team members. Similarly, in waters where visibility is a factor, lighting systems may expand visibility or allow for improved imaging. Everything from basic hand-held lights to large canister-powered lights can also be mounted to full-face masks systems or strapped to the back of a diver’s hand. Again, lights can be operated in a safe fashion that allows the user a full range of dexterity with both hands. Where imaging was once not a factor during subsurface operations, the entire duration of a public safety dive mission can now be recorded and if helpful, illuminated.
Technology has advanced the capabilities and resources available to operational dive teams. With each passing year, new innovations make dive operations safer and more efficient. If dive teams choose to make use of innovative technologies, teams must train to use these items to ensure safety and operational success. It will be exciting to see what comes next and how safe rescue and recovery operations may become in the future.
– Dr. Thomas Powell
Owner/Instructor Trainer – Air Hogs Scuba, Garner, NC