Many commercial divers are

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on the cover Contamina Are You Many commercial divers are unaware of the dangers of diving in polluted water.

Divers also sometimes mistakenly believe the water itself will dilute the hazard to a low level. In both settings, divers can be dead wrong.

The main difference in dealing with a hazardous material underwater is that, in many cases, the hazardous material floats in the water around the diver.

1 on the cover Contamina Are You Many commercial divers are unaware of the dangers of diving in polluted water. Some bodies of water don t appear polluted, yet have high levels of biological or chemical contamination. Divers also sometimes mistakenly believe the water itself will dilute the hazard to a low level. In both settings, divers can be dead wrong. Materials that concern haz-mat personnel topside should concern divers underwater. Primary threats include biohazards and toxic chemicals. The main difference in dealing with a hazardous material underwater is that, in many cases, the hazardous material floats in the water around the diver. Unless the diver equips himself properly, the pollutant may enter the diver s mouth through the regulator in his helmet, his eyes through leaks in a helmet neck dam and touch his skin through his wetsuit. Toxins that float on top of water, like gasoline, present a serious hazard the diver must pass through them to dive or exit the water. Substances that sink are most likely to collect as pockets of pure chemical substance on the bottom. Concentrated chemicals are very hazardous. Perhaps the biggest problem in contaminated water diving is that many divers won t acknowledge the dangers present where they dive. Conceding these risks are present means that they must be dealt with intelligently and many divers don t want to make the effort to take the proper precautions. Such disregard can have disastrous effects. Photo credit: Ryan Miller, A contaminated diver after performing a manhole repair. Photo Credit: East Dive Ltd Spring/Summer 2012

2 By Steven M. Barsky, Marine Marketing and Consulting ted Water Diving: Adequately Protected? Biological pollutants Biological pollutants are probably the most common hazardous materials encountered by divers. Three classes of biological contaminants are of concern: bacteria single-celled creatures that exhibit characteristics common to both plants and animals; protozoans are singlecelled animals; and viruses organisms that take over the chemistry of a host cell in living creatures to reproduce themselves. Fecal coliforms, disease producing bacteria found in human and animal feces, are universally present in the water wherever there is raw sewage or inadequate sewage treatment. Whenever heavy rains fill storm drains and cause waste treatment plants to exceed their capacity, raw sewage spills into nearby waterways. Swallowing water that contains high levels of fecal coliforms can produce severe, disabling diarrhea. It might not kill you but you might wish you were dead! If fecal coliforms are present, there are probably several other forms of biological pollution. Other dangerous bacteria include Cholera, Vibrio vulnificus and Aeromonas hydrophilla. Cholera is a good example of bacteria that can survive in seawater. Like bacteria, many protozoans pose serious threats to divers. For example, eight Photo credit: Jonathan Chapple, Aqua-Lung Canada. different species of Acanthamoeba occur in polluted waters. This deadly single-celled organism causes inflammation of the spinal cord, with death as the end result. Giardia lamblia, another protozoan, causes intestinal pain, diarrhea and high fever. One of the most commonly known viruses, Hepatitis A, survives outside the body in both fresh and salt water, inflaming the subject s liver. Like other disease-producing organisms that spread through contact with raw sewage, hepatitis can be found in fecal matter. Chemical hazards When divers think of hazardous materials emergencies, they often think about accidental spills of toxic chemicals; however, in many situations, divers face serious threats from low level, long-term pollution of waterways. A chemical hazard commonly found in nearly all harbours and marinas is the variety of residues from boat bottom paints. These bottom paints were designed to kill or inhibit the growth of marine life. The same chemicals that discourage marine growth are hazardous to humans. One of the primary components of these anti-fouling paints is an organotin compound known as tributyltin, more commonly known as TBT, which dissolves into fat, giving it the ability to move across the membranes of living cells. This trait is what makes it effective in killing marine organisms, such as barnacles. TBT tends to collect in the silt on the bottom of harbours. Almost all research done on TBTs has concentrated on the effect of these chemicals on marine creatures; however, in a report by the Brookhaven National Laboratory in the US, they note that TBTs have toxic effects on the human nervous system, blood, liver, kidneys, heart and skin. Alarmingly, scientists noted that while people react to a single acute dose of TBTs, repeated sub-toxic doses also produce negative reactions. This suggests a cumulative effect, where low doses keep adding up in the body. Since many commercial dives take place in harbours, TBTs should be of concern, especially to divers working on ship s hulls. A scientist for the US Environmental Protection Agency labeled TBT as the most toxic chemical ever deliberately added to the marine environment. Although tributyltin breaks down in clear waters, it persists much longer in murky harbour waters. Polychlorinated biphenyls (PCBs) pose serious potential threats to divers. Although PCBs are banned in many countries, they were widely used in electrical and hydraulic equipment, paints, plastics and other compounds. They continue to pollute many sites and numerous divers have been exposed to PCBs. Certain chemicals are so dangerous that no diver should consider working around them. These chemicals include but are not limited to: Acetic anhydride; Acrylonitrile; Carbon tetrachloride; Cresol; Dichloropropane; Ethylbenzene; Methyl chloride; Methyl parathion; Perchloroethylene; Styrene; Trichloroethylene; and Xylene. Blood, urine, and stool samples are recommended pre- and post-dive when divers expose themselves to specific chemical toxins. Tests of the divers lung capacity are merited in cases where chemicals are known to affect the divers breathing ability. The risks of diving in polluted water have been scientifically correlated with cancer in divers. Dr. Elihu Richter, head of Occupational and Environmental Medicine at a university in Jerusalem, was the principal author of a paper on the chemical exposure of 682 Israeli Navy continued on page 15 The Canadian Association of Diving Contractors 13

Diving into an underwater radiological environment is a risky undertaking; however, it can be performed safely and successfully with well-coordinated planning and thorough adherence to nuclear safety

3 on the cover Diving in Radiological Conditions: A Precise Plan and Strict Adherence to Safety Protocol By Rebecca Gicante, ASI Group Ltd. An underwater radiological diving environment is contaminated because it contains elements that can pose chronic or acute health risks to the exposed diver and their support personnel. Diving into an underwater radiological environment is a risky undertaking; however, it can be performed safely and successfully with well-coordinated planning and thorough adherence to nuclear safety protocol and contaminated environment diving procedures. Underwater radiological environments and systems typically found in a Canadian Deuterium Uranium (CANDU) Nuclear Reactor Generating Station include primary irradiated fuel bays, secondary irradiated fuel bays, primary and secondary fuel transfer bays and fuel transfer carts and fuel handling systems. All of these fuel bay and transfer bay locations are water-filled, which provides shielding from hazardous radiation fields associated with spent fuel bundles stored within these areas. Additionally, the water provides an active cooling function required for the containment and cooling process of the spent fuel. Spent fuel handling locations require commercial diving intervention as they demand routine underwater maintenance and possibly emergency repair work. The alternative option to utilizing a commercial diver is dewatering but a dewatered environment can be both cost-prohibitive and hazardous since it poses extreme safety risks to the generating station and its operating personnel. Performing underwater diving operations in a radiological environment at a Nuclear Generating Station requires compliance to the authorized nuclear safety procedure. All conventional contaminated environment Radiation exposure affects underwater camera quality. Photo credit: Bruce Power Spring/Summer 2012 diving procedures must also be observed and practiced along with standard commercial diving requirements. A fundamental radiation safety principle used throughout the nuclear industry is As Low As Reasonably Achievable (ALARA), which aims to minimize the radiation dose and release of radioactive materials by employing all reasonable methods necessary. The three basic ways to apply the ALARA principle are time, distance and shielding, which must be implemented into the operational diving procedure, diving crew mindset and adhered to by everyone involved with the operation. Prior to conducting dive activities, a work site survey will be performed by qualified Radiological Protection (RP) personnel. A survey map must be produced that identifies all existing radiation that may be fixed and/or loose. It s essential that the diver can visualize potential radiological hazards in, or near, the dive area on the survey map. As radiation protection is a critical part of the planning process, appropriate dive preparation will be performed. A pre-operational mock-up dive should be conducted in a safe, controlled environment. This ensures the actual dive operation is accomplished in a timely and efficient fashion. Additionally, it minimizes the total amount of diving time spent in the official area of dive operation. All fuel bundles, equipment and fixed or loose contamination must be surveyed, identified and moved, contained or shielded from the area before the diver enters the water. Special precautions physical barriers like lead covers must be used to prevent the diver from coming into close proximity to radioactive materials. When operations are in progress, RP personnel will monitor the diver s Telemetric A diver is closely monitored for contact radiation following a dive in contaminated water. Photo credit: ASI Group Ltd. Dosimetry to ensure the diver doesn t stray from the designated dive area or become dangerously close to a source of radiation. All movement shall be preceded by a working distance gamma survey using an Amp 50 and Amp 100 monitoring probe. The diver will also perform a contact gamma survey before standing on or touching a component or area of work. While conventional industry standard contaminated environment diving equipment is suitable for performing underwater work in an underwater radiological environment, it s extremely important that the following equipment is maintained and pre-dived in a safe, controlled environment before being used: A contaminated environment diving drysuit with fixed gloves must be worn for diving operations in a radiological environment. It must be pre-operation pressure tested and pre-dive leak tested before the diver enters the water. It s recommended that a positive pressure helmet be used in the radiological environment as there is high risk of the diver inhaling or ingesting irradiated water. The diver and designated stand-by/ safety diver must both be outfitted with a Telemetric Dosimetry monitoring system for RP personnel to monitor and record their radiation exposure. Underwater survey instruments (Amp 50 and Amp 100) should be equipped on a long handle and used by the diver for contact gamma surveys to maximize the diver s distance from a potential radiation source. All dive crew and support personnel must be fitted with a thermo luminescent dosimeter (TLD). Although diving in a radiological environment is intimidating and potentially hazardous, it can be performed safely and successfully with minimal to zero radiation exposure for the diver. The operation must be clearly planned and coordinated and all nuclear safety protocols (ALARA), conventional contaminated environment diving procedures and standard commercial diving requirements be fully implemented.

continued from page 13 divers working in the Kishon River since 1948. The river is highly polluted with heavy metals and other contaminants.

What caused the cancer in so many Israeli Navy divers is unknown but there was a strong correlation between diving in the Kishon and cancer that cannot be explained away easily.

This is a combination of everything that washes into our waterways from normal sources, including tire dust from cars, leaking oil and gasoline, fecal matter from pets, as well as pesticides and

4 continued from page 13 divers working in the Kishon River since The river is highly polluted with heavy metals and other contaminants. Richter and his team found a higher level of cancer in these divers than in control populations. What caused the cancer in so many Israeli Navy divers is unknown but there was a strong correlation between diving in the Kishon and cancer that cannot be explained away easily. By far, the largest source of pollution in most places is what is termed non-point source pollution. This is a combination of everything that washes into our waterways from normal sources, including tire dust from cars, leaking oil and gasoline, fecal matter from pets, as well as pesticides and fertilizers. Radioactive hazards Radioactive substances are most likely to enter the marine environment through industrial accidents; however, the possibility exists that terrorists may dump radioactive material into a drinking water supply or harbour. Some divers work inside nuclear plants but are usually well protected due to stringent monitoring in these environments. Thermal hazards exist, too Aside from the risks of exposure to hazardous materials, drysuits and helmets create thermal hazards for the diver during periods of warm weather. These hazards are the same that hazmat personnel face topside, including fluid loss, heat cramps and heat exhaustion. While the diver dresses in before the dive and during decontamination, heat stress can be severe. For divers working in cold water, some heat stress will be relieved during the dive. Moving from warm surface climates into cold water and back to warmer temperatures is stressful in itself. If the diver works in warm water, there is no relief from heat stress. Overheating may be a real danger. In extended contaminated water diving operations in warm weather, the diver s physiology must be monitored, including heart rate, body temperature and weight. Measurements should be taken before and after diving. Selecting the right equipment The basic rule of contaminated water diving is never dive unless you know exactly continued on page 16 The Canadian Association of Diving Contractors 15

on the cover continued from page 15 what pollutants are present. In reality, we know many people don t take time to find out what risks are present. In certain circumstances, this could be fatal.

Keep in mind, there is no drysuit that will protect you from all types of chemicals. There s also no gear that will protect you from strong sources of radiation.

5 on the cover continued from page 15 what pollutants are present. In reality, we know many people don t take time to find out what risks are present. In certain circumstances, this could be fatal. In order to protect yourself, the ideal combination of equipment is a drysuit made from a chemically-resistant material with a mating helmet and dry gloves. Keep in mind, there is no drysuit that will protect you from all types of chemicals. There s also no gear that will protect you from strong sources of radiation. Free-flow helmets are considered good protection from contaminated water because positive pressure is maintained inside the helmet. However, demand helmets can be used successfully, provided the breathing system is equipped with a redundant exhaust system that prevents a back-flow of contaminants in the breathing system. The interface between the diving helmet and the drysuit is critical. Ideally, the helmet should mate directly to the suit with a positive and secure connection. The system should be designed so that few, if any, contaminants are trapped between the helmet and the suit when the two are separated after the dive. Dry suits for contaminated water diving should be made from a material that has a smooth, nonporous outer surface. The material must not absorb contaminants. Dry glove systems consist of a set of cuff rings and gloves (or mittens) that attach directly to the suit. If you are planning a dive in a chemical environment, it s essential to know the chemical compatibility of your equipment compared to the substances you will encounter. Some manufacturers have produced chemical compatibility tables that will give you the acceptable exposure time, in minutes, for their equipment. Permeation time, which is the time it takes for a particular chemical to make its way through a piece of gear at the molecular level, is an essential issue to evaluate. Evaluating these tables is the only way to make an intelligent decision about whether the risks on a particular dive are acceptable. Your exposure time is limited by the weakest piece of equipment you plan to use. Since helmets and suits are made from 16 Spring/Summer 2012

many different materials, you must evaluate your entire diving ensemble, including suit, regulator diaphragm, exhaust valves, dry suit zipper, umbilical, etc.

Diving equipment that has been previously exposed to other chemicals may fail unexpectedly. Get the right training Training for contaminated water diving operations is a complex process.

Ideally, the staff for a training course in contaminated water diving would include a biologist, a chemist, a hazmat specialist and a commercial diver.

6 many different materials, you must evaluate your entire diving ensemble, including suit, regulator diaphragm, exhaust valves, dry suit zipper, umbilical, etc. The wrong decision could cost you your life. It s important to remember that chemical tests conducted by all testing agencies are always conducted on new, unused equipment. Diving equipment that has been previously exposed to other chemicals may fail unexpectedly. Get the right training Training for contaminated water diving operations is a complex process. There is no single expert on this topic. It takes the combined talents of many people to put together a strong training program. Ideally, the staff for a training course in contaminated water diving would include a biologist, a chemist, a hazmat specialist and a commercial diver. The critical points in hands-on training for this type of diving include properly dressing and leak testing the diver s gear, and learning the correct procedures for decontamination after the dive. Since tenders may need to be protected from fumes or chemicals encountered while tending the diver, they will need to be trained in the proper use of personal protective equipment topside. Acknowledge the risks Diving always involves risks and can never be made 100 per cent safe; however, you increase your risks when you refuse to recognize that certain types of dives entail additional risks beyond what s normal. Take time to educate yourself and develop a healthy skepticism so you re properly prepared the next time someone asks you to dive in a high-risk environment. Steve Barsky is a recognized expert on contaminated water diving. He can be reached at smb@marinemkt.com. The Canadian Association of Diving Contractors 17

3.0 Manage. hazardous substances. risks IN THIS SECTION:

3.0 Manage. hazardous substances. risks IN THIS SECTION: 3.0 Manage hazardous substances risks IN THIS SECTION: 3.1 Hazardous substances can damage your health 3.2 Applying substance controls 3.3 Prepare an inventory of your hazardous substances 3.4 Find and