The reality: Every single dive your dive team makes is in a contaminated environment, and regardless of what location, body, or type of water you are diving in, your divers are faced with some type of contaminant. A simple definition of contamination is to make something dangerous, dirty, or impure by adding something harmful or undesirable to it.
Public safety divers face a multitude of operational areas from retention ponds; lakes; creeks; rivers; static to dynamic bodies of water; oceans; ports; harbors; drainage ditches; and, in rare cases, holding tanks and containment structures. These areas contain some sort of contaminant with a varying degree of toxicity and pollution level.
It is imperative that the equipment your divers are wearing reflects on the side of safety and be the right equipment for the style of diving you are trying to perform. Not all manufactured dive gear is suitable for public safety diving, and it should be investigated and proficiently trained on in a controlled environment prior to placing it into operation. Wearing a dry suit is a technical specialty and takes specific training from a credited agency specializing in dry suit diving certification. Check with your local dive gear manufacturer for training.
To help mitigate risks, teams should review National Fire Protection Association (NFPA) 1953, Standard on Protective Ensembles for Contaminated Water Diving. This standard presents minimum design, performance, testing, and certification requirements for protective clothing and equipment items, including dry suit, dry suit gloves, and dry suit footwear designed to provide limited protection from physical, environmental, and certain chemical and biological hazards. Suits in compliance with NFPA 1953 provide a vital minimum threshold of safety for divers.
Work with your local health department, environmental protection agency, or state agencies to provide your team with information on what testing and control efforts are being done in your area. They will be able to give you potential effects of exposure and contaminants that may exist and valuable suggestions on safety precautions for your team. Although it is not realistic to know every contaminant that may exist, the sediment and water quality testing can be achieved and give you a good baseline on what level of exposure protection, equipment, and training you will need.
Types of Contaminants
There are millions of possible contaminants. Some are more hazardous than others, and some may need to be avoided all together even in tiny concentrations and short exposure times.
- Biological contaminants:
- Human sewage, animal sewage, urban and industrial sewage, commercial ships, marinas, agriculture runoff, hazardous waste disposal, urban storm water runoff and marine fresh water organisms, pathogens (disease-causing bacteria, viruses, rickettsia that degrade quickly in water), microbiological organisms, and sediments are all biological contaminants. Viruses such as hepatitis A and B as well as tetanus are also biological.
- Protozoans are single-celled marine and fresh water organisms. The organism known as giardia lamblia is a protozoan and is a common contaminant in fresh water, even in remote and pristine areas. Symptoms are similar to those of E. coli but are usually less severe.
- Toxins are poisonous substances produced by microorganisms; plants; and, in some cases, animals. The most well-known and common toxin is the one known as “red tide.” This is caused by a marine dinoflagellate and can cause gastrointestinal and respiratory problems in humans. This type of algal outbreak is usually associated with large fish kills.
- Chemical and industrial contaminants:
- There are literally millions of chemicals in use today with varying toxicity and permeability. Some of the most common are vehicles in the water, sunken boats, agriculture runoff, and urban sewage.
- Hydrocarbons are the chemical divers are most likely to encounter and include creosote and benzene with low-level long-term exposures. These will float on the surface and do the most damage to dry suits.
- Heavy metals are found in sediments and pose a low risk to divers but are considered systemic poisons. Long-term exposure to these metals can have serious health effects and cause liver, neurological, and kidney damage.
- Polychlorinated biphenyls (PCBs) have been banned in the United States since 1977 but still exist in waterways from early dumping. PCBs do not readily decompose in water and are found in bottom sediments and pose serious health risks in low levels of exposure.
- Pesticides are organic phosphates and can have devastating effects on the nervous system, organs, and tissue. They are most commonly found around agriculture areas and golf courses and should be tested for regularly. Pesticides are difficult to detect and may not be decontaminated properly, making them a high-risk contaminant.
- Chemicals to absolutely avoid include carbon tetrachloride, dichloropropane, ethyl benzene, styrene, trichloroethylene, and xylene. If you suspect the water is contaminated with one or more of these chemicals, do not dive. There are more chemicals than can be covered here, and it is rare that complete information is available in an emergency. One excellent resource is the Chemical Transportation Emergency Center. This group, located in Washington, DC, is sponsored by the chemical industry and is ready to assist public safety personnel who are responding to chemical emergencies. If you believe a chemical has been released into the water and you require urgent information about its effects, please call them at 800-424-9300.They will need detailed information about the incident and the nature of the suspected chemical. This hotline is for emergency use only.
- Nuclear and radiation:
- Diving in any proximity to radiation should only be attempted by specialty trained and specialty equipped personnel. The risk vs. benefit should be obvious in this type of situation and evaluated by your standard operating procedures (SOPs).
- Other factors:
- Heavy rainfall, runoff, and localized flooding in areas outside the waterway banks pose the most common pollution exposure to our teams. These are referred to as nonpoint source pollution. Dog feces, motor oil, fertilizers, and pesticides are examples of these nonpoint exposures.
- Sediments as described above can contain PCBs and heavy metals found on the bottom and along edges of the waterway and should be avoided as much as possible.
- Hazardous materials in areas of tank spill containers, storage tanks, or working around aircraft spills should be taken into consideration for extra protection suits and time spent in this environment.
After working with your local agencies on water quality and testing, you should have a good baseline for dealing with contamination in your area and how to mitigate exposures. Establish good SOPs based on your findings and ensure your divers and shore support personnel are protected with the proper personal protection equipment (PPE).
While most dive teams endeavor to find the perfect equipment for all circumstances, that is rarely, if ever, possible, and compromises must be made. If you do not have the appropriate equipment for a certain type of mission, you should call in additional resources. The amount of risk a dive team is willing to accept will vary depending on the potential for a rescue as opposed to a recovery. Obviously, most public safety divers are willing to accept a higher risk if there is the possibility of saving a life. However, the safety of the dive team is paramount. Teams currently diving in wet suits and open circuit self-contained underwater breathing apparatus (SCUBA) should reevaluate their equipment choices and understand we do not dive in perfect water scenarios in public safety diving-even in training.
Deconning Your Divers
The fire service has taken great strides toward combating cancer within our personnel. The public safety dive team should be no different and should not cut corners in diver PPE. Dive team leaders need to step up the game in protecting our divers and ensure they are not only wearing the proper PPE but that we properly decontaminate (decon) our divers after a dive. Simple Green and mild dish soaps seem to work well for deconning equipment and are fairly cheap. Other cleaners and disinfectants could be harmful to your gear and are not meant for the dive gear and suit materials. Check with your local manufacturer on cleaning practices and how to properly decon your equipment.
Decon should start immediately after the diver exits the water. Tenders and shore support personnel should direct the diver to keep all gear in place, especially the full face mask, and assist the diver to the decon area. Once decon is complete, the tender should assist the diver in doffing dive gear and decon equipment a final time before placing it in the apparatus. The diver must be cautious of areas around the face, nose, and mouth and should not handle food until proper hand washing and face washing are complete. Touching items after a dive could cause cross contamination of everything the diver touches.
Be cautious of stowing dirty or wet dive equipment in bags, compartments, or lockers after a dive. Allow complete cleaning and drying of all equipment and ensure it is in good working order prior to the next dive.
We are the only discipline in public safety that trains in the environment in which we work, and we need to be protected at all times. Keep in mind: If we train like we work, we will work like we train.
Check with your local dry suit and equipment vendors/manufacturers to see what suit may be right for your type/area of diving, and always side on diver safety.