Temperature and Encapsulation
Temperature is one of the major factors that can affect a person’s willingness to dive. There are many divers out there who only choose to dive in warm waters and on calm days. Conversely, there are some people who love to cut holes in ice when they are looking for a fun dive spot. These differing types of diving require very different forms of exposure protection. In warm tropical waters, you may only need a lightweight wet suit, if anything. In icy waters, you may need a dry suit with warm and cozy undergarments. The public safety community is a group that rarely gets to choose its dive location, the weather, or the general environment. For this reason, temperature must be considered when determining diver safety.
If you have ever worked or been involved as a diver in the public safety world, the odds are high that you have donned a dry suit with an attached hood and a full face mask of some sort. A vulcanized-rubber hazmat suit is not the most comfortable dry suit made, but comfort is not the reason you wear that type of suit. Instead, public safety divers often choose to dive fully encapsulated to protect the body from potential hazards and contaminants. The negative side to taking this precaution is that the diver must wear bulky, uncomfortable, and generally hot, protective equipment. Nothing can be more frustrating than sitting by the water working with a tender to get ready wearing a heavy vulcanized-rubber dry suit when it is roughly one hundred degrees outdoors. To be honest, the suit can still grow very hot when outside temperatures are very cool. Remember that these types of suits do not breathe. When your body temperature raises the internal temperature of the suit, there is no cool air available to circulate throughout the suit without breaking a seal. Simultaneously, if you have already gotten into the water, breaking a seal defeats the point of wearing the suit until the diver has been decontaminated.
The first thing to remember about encapsulation and public safety diving is that a diver must rely on his team. A diver must rest and attempt to avoid burning precious calories until he is ready to enter the water. This means that his tender is often responsible for helping him assemble gear (under his supervision), don exposure protection equipment, get to the water, and prepare to dive. The objective is to avoid over-working the diver before he enters the water. The critical factor that must be remembered is that the diver can grow dehydrated simply by sitting in a rubber suit in the summer sun. The whole time the diver may be sweating profusely. For this reason, the dry suit is the last item that should be prepared and then donned before the diver is ready to gear up and head to the water. Simultaneously, the diver should be hydrating as needed in preparation for performing a dive. If you are sweating it out you need to replace it! Another thing a diver or dive team can do to protect divers is to prep gear and divers in the shade. Set up tents as needed or use natural shade to get divers out of direct sunlight.
Underwater, remember that divers can also experience extreme temperatures. If the water is warm and the diver is wearing some form of base-layer undergarment to protect him from experiencing pinches in the suit, he may grow warmer and sweat inside the suit. This type of situation can cause dehydration, diver exhaustion, and other problems. There are systems designed to circulate cool water over the diver’s body, but systems like this are often not cost effective and therefore not available to public safety divers. A diver in this type of situation must be monitored closely to ensure he is safe.
In cold conditions, divers may also experience significant issues. The reality is that many dive teams will purchase high-quality dry suits to protect divers, but the teams will not invest in the various layers of undergarments that a diver may need. Instead, teams often purchase a single set of undergarments for divers to use. This undergarment may not be sufficient to provide warmth for extended dive periods. As a diver spends time underwater, he may begin to grow colder. A cold diver begins to lose motor skills and basic value as a diver for the dive team. There is no reason to keep that diver underwater if he has grown too chilled to perform a proper and effective search.
To protect encapsulated public safety divers, three major things must be considered. First, is there value in the dive? What is the team trying to accomplish and can it be done in an efficient and safe manner? Would it make more sense to perform the dive at a different time? If the environment is too dangerous, dive teams must remember that no dive is worth a diver’s life. Second, tenders are critical to diver safety. A tender has communication with the diver and can determine if the diver is performing in a proper fashion. If the diver seems to be having troubles or may be experiencing an issue, the tender can communicate with the diver to determine the issue and if the diver needs to be pulled from the water. Lastly, public safety divers are tasked with performing patterns, doing finite searches, and carrying large amounts of redundant equipment. These factors suggest that divers of this type can quickly become overworked. Adding extreme temperatures to the situation only further endorses the idea that public safety divers should rotate into the water for short dive periods pre-determined by team leadership. If a diver is too hot or cold, he should not push his limits and remain underwater just to search a little bit longer. This risks the health of the diver.
Lastly, encapsulation is used to protect divers from contaminants. This means that following a dive, the diver must be decontaminated from head to toe to ensure contaminants on the suit are removed and do not touch the diver’s tissue. Decontamination often involves scrubbing and rinsing with various decontamination fluids. This type of action takes time during which a diver may be forced to stand in warm weather while being cleaned.
Diver safety is paramount when considering temperature and how it may affect a diver’s health. Extreme weather and complex equipment designed to protect the diver can also hurt a diver. Team members must monitor divers in these situations, both above and below the surface. If there is a question in regard to safety or a diver’s ability to perform, he should be pulled and checked by emergency medical technicians. The goal of any public safety dive team is to provide a service to communities and other public safety departments. Though these divers accept a certain level of risk, these risks must be moderated and divers must be protected as much as possible by those working with them.
– Dr. Thomas Powell – Owner/Instructor Trainer – Air Hogs Scuba, Garner, NC