Without sufficient advanced training, a typical PSD diver can hardly work safely in water moving faster than 1.25 knots, even from a platform. We can dive in water faster than one-half knot from platforms, because tending from upstream allows divers to perform arcs across the current or vertical box searches when the current becomes more severe. Tending from upstream allows for effective contingency plans.

A functional support rescue plan in two knots or greater requires significant practice. It is not uncommon for bridges to span waterways with such currents. What is astounding is the number of PSD teams with such water in their jurisdictions who were never taught how to calculate a current to even begin to make safe and effective Go/No Go decisions. We meet teams all the time who were taught to look at water movement in cubic feet per second (CFS), which is a volume—not a speed. Moreover, a team cannot calculate CFS on-scene, and CFS does not help teams calculate how far a diver or victim will drift in “x” time and “y” depth. What is the maximum CFS for operations from shore? From a platform?

In addition to entrapment, entanglement, and injury, current can cause significant overexertion if dives are not properly conducted. A diver who typically has a good eight to 10 breath-per-minute rate (bpm) with a 20 psi/minimum surface air consumption (SAC) rate in still water can find himself breathing 22 to 25 bpm in a one- to two-knot current, with a SAC rate increase to more than 100 psi/min. Overexertion can greatly increase the risk of panic, one of the most common causes of diver fatality.

And if all that is not enough, current can cause other problems, such as the following:

• Tenders will find it difficult to impossible to pull divers in against a current greater than 1.5 knots and can find themselves flying into the water if they try. Surface support training and equipment for moving water dives are critical.
• Divers attempting to dive in half masks can have the masks ripped off their face if they turn sideways to a four-knot current.
• Counting a diver’s breathing rate by watching the bubbles becomes increasingly difficult as current increases, which is one of the many reasons electronic communications should be used.
• Chase boats downstream become necessary in case a tender falls in or an accidental diver disconnect occurs.
• Upstream spotters for incoming surface debris may be needed.

Finally, if not well trained, divers have a tendency to overweight more than usual when they dive in currents. Overweighting is dangerous and is a factor in too many diver fatalities.

Floating and Hidden Contaminants

On land. Obviously, there are many different contaminant concerns on land and in confined space rescue. We will accept as fact that they are there and can be problematic.

Underwater. Contaminated water diving is not a joke. There can be fuel oils from cars, trucks, buses, and tankers. Submerged trucks and train cars may have been carrying hazardous materials. Divers cannot read hazmat placards on submerged tankers.

Just think of the procedures used on land to determine if a truck involved in an accident is safe to approach. Think about what is taught to every basic EMT and responding fire rescue company: Look for hazmat signs, approach upwind, approach uphill, stay at least 100 feet away. Yet, what happens when divers are asked to submerge on a collapsed bridge incident with dozens of unknown vehicles when the likelihood is that badly damaged vehicles are lying in all directions and positions on the bottom? Divers enter the water hoping there isn’t a truck lying in its side leaking a chemical that could cause serious harm. Or, perhaps they are not even thinking about it.

What is the team’s contingency plan if there is such a truck? Is a hazmat team on standby at the scene ready to take care of divers and surface personnel? Are EMS personnel prepared to handle possibly contaminated victims if the operation is still in rescue mode?

These considerations are in addition to the river’s normal contaminants. When the team arrives, some contaminants may have already begun gravitating to the surface while others may be waiting for only a slight movement to be released and begin diluting in the water. Standard scuba does not belong in this environment; this is not a simple car in the water—quick in, quick out. Hazmat dry suits that have extensive reported testing are mandatory. Full face masks are mandatory and the minimum. Surface-supplied gas might be mandatory depending on what is potentially in the water.

Should divers be carrying and training in how to use knives or shears/wire cutters? You might wonder what that has to do with the contaminated water issue. When you have seen more than one diver surface with a slash in a dry suit after working an entanglement with a knife, the answer becomes no. That is just one example of many contaminated water diving issues that are too often overlooked.

Pressure Differentials

On land. Unless the operation’s location is at high altitude, atmospheric pressure is not a real concern.

Underwater. Pressure increases by 0.432 psi per foot of fresh water, and Boyle’s law says that pressure and volume are inversely proportional. This means that the deeper you go, the denser the gas you breathe becomes, so you breathe that much more gas with each breath.

Hence, depth directly affects how long a diver’s air will last. The deeper you go, the more air you consume, so the shorter the dive time. Combine that fact with increased work load, and the air goes even faster. As stated earlier, in poor or zero visibility, most divers have no way of monitoring their own gas supply unless they use the trick of duct taping a strong freezer sandwich bag filled with freshwater over their gauge. If you hold the bag up to the mask and shine a small light sideways through the bag, you can read the gauge in the blackest water.

Unless divers are on surface-supplied gas, where the gas supply can be monitored, or you have a tender who knows how to use breathing rates and depth air-consumption rates to make a fairly close air-consumption calculation, there may be no way for divers to know how much of their life support systems is left. And even the best tender in the world can’t figure air consumption without an electronic communication system if the diver or his exhausted bubbles go under something prior to reaching the surface.

Because divers breathe ambient pressure air at depth, they are subject to the risk of serious injury or even death should they ascend more than three to four feet while holding a full breath. Such lung overexpansion injuries as pneumothorax, tension pneumothorax, subcutaneous emphysema, mediastinal emphysema, and arterial gas embolism can result.

There are other forms of barotrauma that US&R teams do not have to be concerned about, such as perforated ear drums, round window rupture,5 sinus squeeze, and suit squeeze.

In dive operations at altitudes greater than 1,000 feet, the pressure differential is compounded by the reduced atmospheric pressure. At some high altitudes in Colorado, for example, instead of having to go to 34 feet in a sea level lake, a diver has to go only to 25 feet to reach a second atmosphere absolute to increase the pressure by twice that of the surface. The high altitude diver at only 25 feet will use the same amount of air when at 34 feet sea level.

Debris

On land. Debris hung or supported tenuously is dangerous no matter how you look at it. Of course, there is the fact that you can look at parts or all of it on land. More often than not, you cannot see it underwater.

Underwater. Not only can we not see the debris, but our movements can affect it. For the most part, PSD divers are bottom dwellers, crawling along the bottom. As an industry, PSD divers do not typically understand buoyancy control or suspended weightless diving. PSD divers have a tendency to be well overweighted and may not understand how little a movement it takes to alter a suspended object in the water. We typically remove an average of six pounds of lead from our PSD students, and it is not rare for us to remove as much as 10, 15, or even 20 pounds from a diver.

Most PSD divers do not have midwater skills capable of allowing them to be physically quiet in the water column. Because of the lack of visibility, they often do not know when they have moved into or under something. Until they touch it, they don’t know it is there. The simple act of removing a human body can alter an entire support system. Divers cannot know how their exhausted bubbles are affecting the objects above, whether they are eroding support or allowing contaminants to be released.

Unless you have had extended-penetration wreck-diving experience or training in this type of large-debris environment, this is a whole new ball game, and only fully trained, experienced divers belong there.

Sharp or jagged debris can cause injury, entanglements, and entrapments. How many PSD divers have practiced swimming through hula hoops or obstacle courses while being blacked out? Far too few. Yet, this lack of training/experience would not stop some teams from attempting to dive in a bridge collapse incident.

Support Vessels

On land. Knowing where to place support vehicles and how to access the operational area is of key importance.

Underwater. These operations require well-placed vessels/platforms that are multianchored properly so they become little islands placed in proper positions for direct line/umbilical access to the operational area based on depth and speed of water, all mathematically calculated. The average dive team, if it has a boat, does not have the proper anchors, chain, and length of line to secure a vessel in this fashion. Very few teams know how to properly secure a three- or four-point anchoring system. A properly anchored platform must be able to have its position adjusted (in, out, left, right) on command, but not by accident. Such platforms need to be environmentally all-conditions-capable and contain all needed life support.

Mutual Aid

On land. The small and major disasters that have occurred over the past two decades demonstrated that urban collapse teams can come together from all over the country, and even from all over the world, to work effectively together. A team from northern California can work with a team from southern Florida.

Underwater. This is definitely not true for PSD teams. As described earlier, teams in neighboring counties are likely to have very different equipment and are also likely to have differences in procedures that would make it very difficult for them to work together. For example, we train divers with a blackwater hand-signal system so a primary diver can communicate “I am entangled here,” “I am hurt here,” “I am out of air” (which means the diver is breathing on pony bottle air), and “I am ready to ascend with you.” Other trainers instead might use the approach of having only backup divers go down and figure out what the problem is, which can  result in lost time, higher stress, dislodged regulators/masks, and further impalement on a fish hook. Such different contingency plans are not compatible.

Tenders/Trained Surface Support Staff

On land. Support or operational personnel need training in the specific operational needs. Again, land teams train all the time; members practice their skills. Operations and technician members know how to work together and what to expect from each other. They can count on each other.

Underwater. A good tender may have to be a more highly trained person than the diver. Tenders are professionally trained and are responsible for every aspect of the diver’s safety, including all equipment and procedure issues. A tender is also responsible for putting the diver in the correct search area and for deciding if a searched area can be secured or should be re-searched. A diver has only two jobs—keeping the tether line taut and using the mind’s eye to search. Tenders are keeping track of times, breathing rates, diver locations, tether line distances, diver air consumption, snags, diver search speeds, and much more.

Tenders can feel the diver’s every movement and understand how to respond to that need. They know when the diver’s tether or umbilical is entangled and what to do about it. They know how to communicate through a line to keep their diver safe when the electronic communication system goes down. They know how to dress the diver. They truly understand everything about the job and the dangers the diver may encounter. They can run professional contingency plans. A good tender can make a less experienced diver look good, get the job done, and be safe the whole time.

•••

After training divers around the world in all kinds of environments for more than 40 years, we advise every team we train to ask the following questions: Are we capable of this job? Is there a life that can be saved other than our own? Have we trained for this type of operation? What can possibly go wrong? Do we have a realistically trained and practiced plan for getting out our own? If you do not know how you would get your people out, do not put them in. Don’t go in.

Very few teams have the equipment, the training, and the practiced contingency plans to perform a fast-moving water bridge collapse operation effectively and, most importantly, safely. If communities want PSD teams to respond to such incidents and enter such waters, they need to provide the funding for them to do it  right and safely.

All PSD teams should sit down and seriously discuss the types of water operations that pose the highest risks in their jurisdictions and then realistically assess what they are capable of doing safely now. Other issues that should be discussed include the types of operations the team wants to grow toward, what needs to be done to accomplish that, and how to identify the potential Go/No Go operations and ensure that every officer and team member understands that a No Go operation is a “stay out of the water” incident. A bridge collapse is just one example most of us have to consider.

Endnotes

1. 0.432 psi/ffw, 0.445 psi/fsw

2. We say “situation” instead of “emergency,” because if divers are properly trained, are wearing quick-release pony bottles, and have a contingency bottle on-scene, then a loss of primary air is simply an inconvenience, not a life-threatening emergency.

3. A common misconception is that pony bottles are entanglement hazards. This is not true when the bottles are worn properly and divers need a true alternate air source, particularly in view of the potential for entanglement hazards.

4. The minimum current to be considered swiftwater according to National Fire Protection Association (NFPA) 1670, Standard on Operations and Training for Technical Search and Rescue Incidents. What may be minimal for surface swiftwater operations, though, can be considerable for underwater operations.

5. If the diver blows too forcefully during the Valsalva ear-equalization maneuver, the round window between the middle and inner ear could perforate, resulting in serious, long-lasting vertigo, vomiting, and infection.

Training and Maintenance Requirements for PSD Teams

Most dive teams started with a few firefighters or police officers with recreational scuba certifications who wanted to help their communities. They dove for fun in the local lake or quarry. They combined their fire or law enforcement know-how with their sport diving experience and equipment to operate as search divers.

There are many problems with this. Sadly, people do not drown only in water considered safe for sport diving. They drown in fast-moving rivers and contaminated water, they drown in submerged vehicles, and sometimes they die under very thin ice. And, as the country tragically saw this summer, dive teams may be dispatched to a disaster like a bridge collapse. The difference between diving in a local neighborhood lake and a bridge collapse disaster is equivalent to the differences between fighting a small house fire and working a fully involved high-rise with realistic collapse potential.

The norm still seems to be to take a basic sport diving class, which is not designed for rescue work and provides only the basics for recreational diving. At the end of the class, you are in business and can go underwater. Consider also that some sport diving courses may have been a 16-hour weekend wonder, as opposed to the 35- to 45-hour open-water program that teaches strong basic skills.

The key word to start with is “basic,” because that is what the vast majority of dive teams that have PSD certifications have as their maximum level of training. Basic PSD certification does not get you in a fast-moving river or contaminated water and certainly does not make a team prepared to dive around, over, and under major debris in still water, let alone moving water.

VISIBILITY

Below are a few examples of what basic low- to zero-visibility PSD involves:

• Divers must be confident and have reflexive, strong, entry-level skills such as powerful kicking skills, comfortable underwater breathing without a mask, a relaxed breathing rate of six to 12 breaths per minute during basic searches, good neutral buoyancy control skills, and two-second/foot blackwater ascent rates.
• An operational plan must be developed and a command system for diving must be implemented.
• To allow divers to search with both hands simultaneously, the diver should dive alone, be tethered, and be directed by the tender through the diver harness.
• The diver must know how to conduct arc, dock walk, and vertical box searches (for bottoms with tall grass or heavy debris) from shore in water moving at less than 0.5 knots (50 feet/min) and from boats or other platforms in water moving less than 1.25 knots (125 feet/min).
• Tenders must know how to calculate and document a diver’s breathing rate to figure out how much air a blackwater diver has at any point during the dive within about 200 psi.
• Tenders must know how to manage line snags.
• Training should include developing hands-on blackwater contingency plans for out-of-air situations,2 entanglement, out-of-air with concurrent entanglement, and injury.
• -Practice using a true alternate air source such as a quick-release pony bottle,3 followed by a contingency bottle or contingency surface supplied air.
• -Divers must learn how to use basic cutting tools to save themselves or other divers.
• -Develop blackwater communication between primary and backup divers when electronic communication systems fail or are not available.
• The ability to draw accurate search profile maps as the diver moves to document what ground was covered and what was not.
• Produce court-ready documentation after each dive to show whether or not a diver’s search area can be secured or needs to be re-searched in part or whole. This will tell subsequent tenders where to put their divers.
• The ability to determine the most likely location of the search objects based on scene evidence, witness reenactments, interviews, witnesses’ written statements, and environmental conditions and variables.
• Employ techniques for preventing accidents such as the following: duct-taping outside fin straps, wearing gauge and dry-suit hoses under the arm through the BCD armhole, capable of maximum dive times in good conditions of 20 to 25 minutes, always returning home with at least 1,000 psi, not exceeding maximum depths of 50 to 60 feet, using a tether line with a maximum length of 125 feet, diving at a 45° degree angle away from the tender to keep the line continuously taut, ditching weights before exiting the water, proper weighting, making sure inflated BCDs do not float divers face-down on the surface, predive facial acclimation, documenting diver breathing rates every five minutes, documenting diver movements with premeasured and marked tether lines, and standard operating procedures that list what teams can and cannot with their current level of training and equipment.
• Recognize when the operation is beyond your scope of training and capabilities.

These are just some of the many skills divers and tenders should learn in an entry-level PSD training program.

However, learning and practicing the basics are not enough for teams that want to conduct advanced dive operations such as those involving submerged vehicles, ice diving, moving-water operations, large-area or deep extended-range dives, and contaminated water.

Most times, team members or budget decision makers do not see the necessity for advanced training. This is amazing when you watch the tens of thousands of firefighters who pour into such excellent shows as FDIC every year for hands-on training, purchase training materials, and attend seminars to strengthen their basic firefighting skills and to learn advanced ones. The fire service and the land-based rescue community understand that advanced training and equipment are required for advanced operations. Why does this not carry over to water operations?

WALT “BUTCH” HENDRICK, the founder of Lifeguard Systems, has been training public safety dive teams and surface rescue personnel for more than 35 years in more than 15 countries and is an innovator, international award winner, and contributor to the water rescue/recovery industry. He began his dive career in the late 1950s in his family’s water sport resort in Puerto Rico. Among the hundreds of teams he has trained were those for the Washington, DC, FAA; U.S. Parks Department; Fire Department of New York; U.S. Coast Guard; Malaysian Fire Rescue; National South African; NYC DEP, and 210th Rescue Squad Para Jumpers. He has hundreds of published articles, plus several videos and books, including Public Safety Diving, Ice Diving Operations, Homicidal Drowning Investigation, and Surface Ice Rescue.

ANDREA ZAFERES is a course director for Lifeguard Systems in Shokan, New York.