Demystifying Rebreather Scrubbers, RF4 Malta

Rebreather Forum 4, held in 2023 in Malta was yet another Herculean undertaking by Michael Menduno, the executive editor of Global Underwater Explorer’s (aka GUE) InDepth magazine and various international publications (see the above link for details.) Michael was the journalist who coined the term ‘technical diving”, and also created Aquacorp Magazine.

I’ve known and appreciated Michael for decades and gave presentations at his Rebreather Forums 2 and 3. My role on the RF4 Science Panel was to help select the best speakers for the Forum, to herd cats when necessary, and to speak.

The Book

Of course, with a new book (basically a textbook) on one of the most mysterious and technical aspects of rebreather diving, I spoke on the subject of “Demystifying Scrubbers”.

Photo courtesy of Rosemary Lunn

Breakthrough can be found on Amazon in paperback or Kindle, or elsewhere in ePub format.

Photo courtesy of Axel Schoeller (1963-2023)

Presentation Description

Here, I’ve borrowed Menduno’s own words describing my talk.

Plunge into the intricate world of rebreather diving safety and techniques with retired scientific director of the US Navy Experimental Diving Unit (NEDU) and author, Dr. John Clarke, who illuminates the inner workings of rebreather CO2 scrubbers, based on extensive research work by the US Navy and his own modeling efforts. This talk unveils the critical aspects of CCR diving gear selection, especially focusing on the importance of rebreather CO2 scrubbers, soda lime quality, and the proper maintenance of canister duration to ensure diver safety.

From the influence of cold water on CCR diving equipment to the vital role of physiological variation among divers, discover how individual differences significantly impact rebreather canister duration and CO2 absorption rates. Engage with real-life scenarios and experiments that shed light on the potential dangers of compromised soda lime; explore the implications of using indicating soda sorb without proper Navy notification (leading to catastrophic failures in rebreather functionality). Moreover, the discussion covers simulated physical models that offer insights into the dynamics of CO2 absorption in rebreather diving. The models emphasize the importance of understanding your CCR diving equipment and recognizing when changes, no matter how slight, in soda lime granule size or distribution might signal a risk. This video is an essential watch for any rebreather diver seeking to deepen their safety knowledge, highlighting the blend of technical expertise, physiological awareness, and practical vigilance required to navigate the underwater world securely.

Michael Menduno

Video

The video of my entire talk can be viewed here.

All RF4 Presentations

All of the RF4 presentations are available at this RF4 link. It is chock full of the best information available, from the best presenters in the field of Rebreather Diving.

Great Balls of Fire, Plasma

The first impression from the Fire Chief was that my childhood home had been firebombed.

The Event

As my Father headed home one afternoon in 1958, he had left behind the hectic traffic of Kansas City, Kansas. He was approaching the bedroom community of Prairie Village, Kansas, when he had to stop as a procession of fire trucks, sirens wailing, pulled into the road ahead of him.

Once traffic was moving again, he remained behind the fire engines. They happened to be headed his way. A few minutes later, the speeding trucks made a quick turn to the right as they entered a community of neatly shuttered Cape Cod homes less than ten years old. Coincidentally, that was where he needed to turn.

The vehicles slowed only slightly as they entered quiet residential streets. Young children leaving a nearby elementary school stared at the noisy procession. But oddly, the firemen were still heading in the same direction my Father needed to go.

He could now see smoke in the air as he approached within a quarter-mile of our home. And then, he shuddered as he watched the trucks turn up our street. Seconds later, he watched the trucks stop in front of our house, the Cape Cod house with a dense gray cloud of smoke billowing from it.

As he parked as close as the fire trucks allowed, he saw far more smoke than flames. Some would think that was a good sign, but he knew from painful experience just how deadly smoke can be.

When he was a teenager, he lost his Father to smoke inhalation in a hotel fire. So now, he was close to panic. His wife, my mother, had been alone in the burning house.

At first, all he could focus on was firemen dragging hoses through the open front door and smoke pouring out the door into the front yard. Then with great relief, he saw Mom standing on the opposite side of the street, surrounded by handfuls of neighbors. She ran towards him, seemingly safe, but of course, shaken.

Fortunately, she had been in a front bedroom when the stove exploded. She managed to escape out the nearby front door.

Modern-day photograph of the living room and front entry of the house. The open door to the front bedroom can be seen across the hallway. The kitchen and dining room are to the right of this photo.

Aftermath

Something had detained me that day, either my safety patrol duties or the principal. I don’t remember which. As I turned up my street, an excited boy about my age, twelve, announced that I had missed a “cool” fire. But as I walked up the road, I saw that I was about to witness the fire’s aftermath, up close and personal.

The dining room was a mixture of charred furnishings and wet soot dripping down the walls. The glass in a window facing the back of the house had been shattered, leading to the initial assessment that an incendiary device had been tossed into the house.

The adjoining kitchen also had some fire damage, which was strangely limited. A charred path rose up to the ceiling from behind the stove and then angled over to the back door. Reaching the back wall, the path turned downward. One side of a curtain framing the glass in the back door was incinerated, a few blackened strands of cloth left dangling. Only a foot away, the right-side curtain panel was untouched.

A plastic wastebasket sat at the back door just underneath the left curtain panel. Oddly, the half of it closest to the door had been melted into a dark puddle. But the other half of the wastebasket was undamaged. The degree to which the heat had exacted its cautery was almost surgical.

Only two feet away from the strangely cleaved wastebasket was the open door that separated the kitchen from the dining room. Although the dining room was blackened by fire and smoke, the kitchen was largely unaffected, except for that curiously defined path of charred paint.

On top of the stove was a squat cylinder that filtered and stored bacon grease. Although the fire chief was suspicious that the bacon grease container might have been the source of the fire, its contents were untouched.

The grease can was topped by a handle made of black Bakelite plastic, somewhat like the one pictured below.

Strangely, exactly half of that knob was charred, the side facing the back of the stove. However, the side facing the room was untouched. One side of the knob was briefly exposed to intense heat, while the other was not.

Discovery

When the fire investigator pulled the stove away from the wall, they saw that the 220-volt wires had shorted out. He suggested that imperceptible vibrations coming from the ground, or the effect on the house’s wooden framing of sometimes-violent Kansas winds, had caused the two large loops of high amperage copper wire to rub together.

That rubbing slowly chafed through the asbestos insulation separating them. The investigator guessed that the wear was imperceptibly slow until, at last, the power lines arced. Violently.

It has taken most of a human lifetime to explain what happened that day.

When 220-volt lines arc to ground, there can be an instantaneous current of several thousand amperes surging through the wires until the screw-in fuses of the era blew, robbing the circuit of power. But the damage had already been done.

1950s era screw-in fuse box

In the intervening moment before the loss of power, the arc generated enough heat to cause a plasma of ionized copper atoms and suddenly freed electrons. The copper wires were not just melted; they were vaporized and turned into a chaotic ball of superheated positively charged atomic nuclei and negatively charged electrons.

Image Credit: Caroline J. v. Wurden and Glen A. Wurden, Los Alamos.

Enriching the copper plasma was plasma from the air itself, nitrogen, and oxygen. You see, at plasma temperatures of thousands of degrees, electrons are ripped off molecules. Vaporized insulation would also have joined the ball of plasma.

A model of our Prairie Village kitchen, with an artist’s impression of a plasma ball rising from the back of the electric stove.

The 4th State of Matter

Plasma is said to be the fourth state of matter (solid, liquid, gas, plasma). Arguably, it’s the most common state of matter in the universe. You can buy your own “plasma ball” as an object of curiosity for your home, like in the photo below. However, an unconstrained ball of plasma is altogether different. It’s not a good thing to have running loose inside your home.

Photo by Solstice Hannan on Unsplash

Due to its incredibly high heat, plasma becomes buoyant, rising in the air. As the fire investigator noted, the approximately 8-inch-wide path of charred paint in our kitchen made it easy to follow the plasma’s path as it rose up the wall behind the stove.

Upon reaching the ceiling, the upward momentum of the seething ionic mass was diverted across the kitchen ceiling, angling towards the back door. Like a billiard ball ricocheting off the edge of a pool table, the sun-like ball then careened downward, incinerating the left-most curtain on the door and consuming half of the plastic wastebasket lying directly below.

Upon encountering the tile floor, the ball’s momentum carried it at a right angle through the open door and into the dining room.

Once there, the plasma ball exploded.

The entire house would have burned down were it not for the fast response of the firefighters. If the house had been fully involved in the fire, the charred trail in the kitchen would have been destroyed. That trace is what provided evidence of the passage of a buoyant ball of sun-hot plasma.

Short Circuit Demonstration

To explain the physics of short-circuits, the following images are helpful. They were screenshots from the Warped Perception YouTube Channel and the video titled, Fuse vs. Circuit Breaker Which Blows Faster (Slow Motion).

The next two frames from the video involved crossing wires attached to 110-volt wiring and a circuit breaker.

A high-speed camera was used to capture the time course of plasma generated by short-circuiting the copper wires. Shown below, the initial vaporization of the short-circuited copper wires produced the greenish-blue coloration expected for copper plasma. The contacts in the circuit breaker (inside the white circle on the lower left of the image) had not yet separated.

In the next frame, within a few milliseconds of plasma initiation, the circuit breaker contacts had opened, and the plasma started interacting with the surrounding air, creating a yellowish-white light. With the circuit broken, the current source had been removed. However, the plasma continued to grow, changing color as air and other things became ionized due to the extreme but highly localized heat.

 Because of the relatively low 110-volts, the resulting plasmas were slight in comparison to the amount of thermal, electrical, and magnetic energy that must have been created in our stove’s 220-volt short-circuit. So, imagine an instantaneous current of several thousand amperes creating a ball of plasma almost a foot wide, shooting with a large bang out of the back of the stove.

Event Illustration

In the following sequence of illustrations depicting the kitchen and dining room of the house, the path of the plasma ball is marked by a trail of soot.

The damage in the kitchen was limited to a small fraction of the room. Once the ball of plasma rolled along the floor into the dining room, fiery chaos ensued.

An approximation of the dining room before the fire. The living room, seen through the opening on the right, suffered only smoke damage.

The Enigma

Plasmas caused by either electrical shorts or other energy sources such as microwave ovens can generate temperatures over 6000 K.  However, typically those hot plasmas disappear rapidly once power has been removed. Such plasmas do not form a ball that travels across a room. Yet, if we were to believe the experienced fire investigator and our own eyes, that is precisely what happened in our house. It was undeniable that the kitchen range had exploded, but the most significant fire damage occurred in an adjoining room. The kitchen was scarcely touched.

Ball Lightning

There is one type of glowing sphere that can travel some distance while maintaining its luminescence and destructive ability. It’s called ball lightning, a mysterious phenomenon that many scientists still doubt exists. However, within the past decade, hard evidence of ball lightning has been revealed by happenstance.

In July of 2012, a fortuitous observation was made by Chinese scientists J. Cen, P. Yuan, and S. Xue. In 2014 they published their findings in a paper titled Observation of the Optical and Spectral Characteristics of Ball Lightning. Their report was published in Physical Review Letters, a premier physics journal published by the American Physical Society.

One of the first descriptions of the above article in the easily accessible lay press was by the science writer Brian Dodson. His introduction of ball lightning is not only informative but relevant to the incident in our home. He is quoted below.

The reported size (of ball lightning) is usually between 1 and 100 cm (0.4-40 in), with the most common size being 10-20 cm. They do not tend to be extremely bright, usually appearing rather like an incandescent lamp in surface brightness. Colors include red, orange, and yellow.

The balls persist for times between about a second and a minute, and tend to move at a few meters per second, often, but not always, horizontally. They seem to be able to pass through closed doors and windows, and even penetrate areas which are usually proofed against lightning. Their final decay is usually rapid, and can range from benign to rather large explosions.

After that introduction, Dodson described what the Chinese scientists had observed.

Physicist Ping Yuan and his team from Northwest Normal University in Gansu Province, China, had positioned spectrographs to investigate lightning on northwest China’s Tibetan Plateau. They recorded both a spectrum and a high-speed video of a ball lightning that appeared following a cloud-to-ground lightning strike which struck about 900 meters (3,000 ft) from their spectrographs.

While the apparent size of the glow on the spectrograph was about five meters (16 ft), the physicists report that the actual size of the ball was “much smaller,” bringing the observation into accord with historic reports. The color of the ball changed from its initial white to a reddish glow during its persistence of just over a second. It was observed to drift horizontally about 10 meters and ascend perhaps 3 meters during its life.

Data

The spectrograph revealed prominent spectral lines from silicon, iron, and calcium, expected constituents in vaporized dirt.

Sand is primarily silicon dioxide, with two oxygen atoms bound to a single silicon atom. According to at least one source, a self-sustaining plasma can form when a high-voltage spark and the heat from copper plasma (from the shorted wires), drives oxygen ions away from the silicon atoms. The plasma ball can somehow be sustained and even grow when oxygen from the air reenters the plasma during the short lifetime of the plasma ball.

The Asbestos Connection

 For many years, asbestos was used as insulation on wires due to its strong thermal and electrical insulating properties. Without a doubt, an electric range manufactured in 1950 would have had asbestos-based insulation on the 220-volt wiring. The use of asbestos in stoves was essentially banned in 1977, twenty years after the fire.

The most common and useful form of asbestos, Chrysotile or white asbestos, is a hydrated magnesium silicate with the chemical formula 3MgO·2SiO2·2H2O. From the known atomic ionization energies, we know that if there is enough spark-energy to ionize oxygen, then there is more than enough energy to ionize both magnesium and silicon atoms.

Since J. Cen et al. discovered the spectra of silicon in ball lightning, it is reasonable to assume that both magnesium and silicon were in abundance in our plasma generated from asbestos-insulated copper wiring.

Nexus

The facts of the plasma ball’s track and the eventual explosion were readily apparent to the trained eye of the fire investigator back in 1958. However, it seems that the knowledge of how such a fireball could travel from one room to the next and eventually explode could not have been known until recently. Thus, it has taken most of a human lifetime to perhaps explain the bizarre events of that day.

I am curious about an overly simplistic nexus combining the known features of high-temperature plasmas and ball lightning. We now know that naturally occurring ball lightning generated from ground strikes emits the light spectra of vaporized silica. The most common form of asbestos insulation contains equal parts of silicon and magnesium. I wonder, could vaporized asbestos have been partially responsible for creating a long-lasting but contained ball of plasma—in my house?

Of course, before being taken seriously, this guess about the potential role of asbestos insulation in short-circuited 220-volt wiring really should be tested in a laboratory. While I would love to see a demonstration of that potentially naïve hypothesis, let me state the obvious. This would be an inherently dangerous experiment.

It would have to be conducted under carefully controlled conditions by fire and electrical hazard-wise professionals. It might also be prudent to have firemen and EMTs standing by, just in case.

A Cloud of Smoke is No Way to Go

Smoke inhalation is a rapid and ruthless killer. It is the number one cause of death from fires.

I learned that lesson the hard way. Long before I was born, my Grandfather Clarke died of smoke inhalation during a fire at the Hotel Kilgore in Fordyce, Arkansas.

Kilgore Hotel, 1912 – 1928, Fordyce, Arkansas

Wild Fires

You don’t have to be in a burning building to be exposed to large quantities of smoke. During every fire season along the Pacific Coast, vast areas come under threat of predicted hazardous smoke conditions.

2020 fire season. https://fire.airnow.gov/

The following graphic illustrates the most important factor of wildfire smoke inhalation; the size of the smoke particles. The smallest particles are inhaled deep into the lungs and cause the most lung and circulatory damage.

An Air Quality Index (AQI) and associated warnings are updated online every few hours from an EPA website. The AQI can be found for any geographical location in the U.S. based on data from air monitoring stations.

Cloth masks will not protect you from wildfire smoke.

According to the CDC, cloth masks that are used to slow the spread of COVID-19 by blocking respiratory droplets offer little protection against wildfire smoke. “They do not catch small, harmful particles in smoke that can harm your health.”

The protective capabilities offered by N95 masks are largely attributed to the masks’ certification to remove at least 95% of all particles with an average diameter of 300 nm (0.3 micrometers, or microns).

The relative size of a symbolic N95 filter pore (300 nm) and average-sized SARS COV-2 virus particles (100 nm). In this illustration, seven viruses fit side by side in a single filter pore opening.

A smoke particle 2.5 microns in diameter is equal to 2,500 nm. So, in principle, the majority of smoke particles should be excluded by the 300 nm wide pores of a non-leaking N95 mask.

But the secret to success is in eliminating leaks. Inexpensive N95 masks are rarely properly worn, removing leaks around the mask. The N95 mask below, however, is specifically designed to prevent leaks on inhalation. It uses a gel seal around the face.

This N95 mask has a gel seal to prevent inhaling contaminated air around the sides of the mask.

This particular mask has an exhalation port, thus easing exhalation breathing resistance, as do many N95 masks for the construction industry. Obviously, medical workers won’t allow patients to wear them because the patient exhales their viruses into the clinician’s face.

However, for those trying to preserve their lungs during a high smoke alert like those shown here, the masks should be ideal, though pricey.

The outer facing side of the envomasks.

The white filter inserts are disposable and are meant to be replaced on a regular basis once they are soiled by foreign particles.

[This writer has no tie to the manufacturer of the above masks. I was given one by a company CEO when I was working for them during the beginning of the COVID crisis. I liked it so much, I bought one for my wife.]

Even an N95 mask will not protect from some smoke particles. For instance, cigarette smoke particles have been measured to be less than 200 nm in diameter.

Clean Air in Florida

Above is the EPA AQI graphic for Panama City, Florida in September 2020. All of the following graphics were obtained contemporaneously from government websites. (I delayed publishing this post until the science article referenced at the bottom was published.)

Western Air Quality in September 2020

September 2020 was a really bad month for breathing out west, due to a multitude of wilderness wildfires. For instance, in Portland, Oregon on the morning of September 12, the AQI was near the top of the very unhealthy range.

“Avoid strenuous outdoor exercise, keep outdoor activities short, consider moving physical activities indoors.”

At the same time, the AQI was near the top of the Hazardous range in Eugene, Oregon.

As seen from the data from a permanent monitor in Eugene, the air quality went from good to bad very abruptly as the smoke from forest fires spread.

The Santium Fire

As forwarned by images like that taken on September 8, 2020, Salem, Oregon was soon to come into harm’s way. The smoke from the large Santium fire had reddened the sky.

By Bruhmoney77 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=94007295

Four days later on the 12th, the AQI in Salem was literally “Beyond” bad.

The EPA warmed Everyone to stay indoors and reduce activity levels.

Visual Comparison

On August 29, 2020, the web camera onboard the R/V Oceanus based in Newport, Oregon, recorded the following image facing forward over the ship’s bow.

By noon, September 12, the AQI had increased dramatically. The AQI was 280, very unhealthy.

Visibility was nil; not from fog, but from wildfire smoke.

Science

On December 6, 2021, there was a paper published in the journal Wilderness & Environmental Medicine. The article is titled Cardiovascular and blood oxidative stress responses to exercise and acute woodsmoke exposure in recreationally active individuals. It was a laboratory study that addressed the consequences of short-term (45-min) exposures to woodsmoke during moderate-intensity cycling exercise.

The researchers expressed smoke concentration in scientific terms, micrograms of smoke particles for each cubic meter of air. To convert that concentration into EPA terms, AQI, we can use the table below, the 2012 update to the EPA’s Air Quality Index standards. It translates the conversion from AQI (second column from the left) to the concentration of woodsmoke for a 24-hour average, on the far right.

The above University of Montana researchers exposed young, active volunteers to 250 micrograms of smoke particles per cubic meter of air. If that exposure had lasted for 24-hours, it would have been at the border of the EPA’s Very Unhealthy and Hazardous AQI. But for a 45-minute exposure, no discernable physiological effects were noted.

Conclusions

Although exposure to heavy smoke and toxic vapors from fires can be immediately lethal, such exposures are relatively rare. On the other hand, multitudes of people can be exposed to woodsmoke during a particularly bad fire season, like that on the west coast from time to time.

The important takeaway from the above research is that when needed to escape from a fire area, short exposures to even Hazardous levels of woodsmoke can be tolerated. However, the emphasis is on short timeframes.

For longer exposures, tightly fitting masks like that pictured above will provide the best respiratory protection.

The Most Important News You Didn’t See Coming

In June of 2021, the Director of National Intelligence made a guarded announcement that UFOs/UAPs might be of extraterrestrial origin.

UFO experiencers greeted that revelation with amusement. In terms of the childhood searching game hot and cold, the ODNI statements were “lukewarm” as far as searchers for truth were concerned.

Mind you, lukewarm is far better than the frigid denial that existed a scant ten years ago. This new attitude, forced by the encounters of Navy aviators with bizarre aerial phenomena, is refreshing. It represents yet another crack in the UFO-denial barrier that has long blocked serious discussion of the matter. So, even lukewarm is welcomed by truth seekers.

Eric Haseltine

Eric Haseltine, Ph.D. is a neuroscientist having served in the National Security Agency (NSA) and the Office of National Intelligence (ODNI.) Reportedly, he was the Associate Director of National Intelligence.

On November 29, 2021, Haseltine reported in Psychology Today his take on the June ODNI Intelligence Report on UAP.

Quoting Haseltine:

 I was stunned when the Office of the Director of National Intelligence (where I was Director of Science and Technology) issued a report this June, Preliminary Assessment: Unidentified Aerial Phenomena (UAPs).

What he said next was remarkable.

The objects either represent exciting extensions of known science (such as directed energy physics) or exploit features of exotic unknown science (such as faster-than-light travel through gravitational worm holes).

No doubt in keeping with his Nondisclosure Agreements, Haseltine chose the safe route and discussed the possibilities that UAPs might be using known science. However, he did offer the strange theory that UAPs may have zero mass.

Thankfully, Haseltine raised the informational temperature a tad higher than room temperature. But the feeling I got was that for understandable reasons, he left out the good stuff.

NASA’s Bill Nelson

NASA Administrator Bill Nelson, a former Army Captain, and NASA astronaut, recently made an intriguing observation. During a 19 October interview hosted by the University of Virginia Center for Politics, Nelson said that while he didn’t know the source of the “UAPs” that were daily hounding Navy aviators, he did believe that the most credible theory was that they were extraterrestrial—and possibly extradimensional.

In childhood game parlance, Nelson was getting “hot.” The notion of extradimensional raises a whole new level of scientific interest. In journalistic terms of what, when, and where, the most critical question, how, is finally being publicly voiced.

Luis Elizondo

But what the heck does extradimensional mean in laymen’s terms? Well, Luis (Lue) Elizondo recently told us in an interview published by GQ, Gentlemen’s Quarterly. His explanation is in game-speak, “burning up.”

Luis Elizondo in his November 2021 GQ Article

Here is a long but informative quote from that article.

“The proposed new UAP office would have to report on health-related effects for individuals who have experienced UAPs. What kind of thing might happen if you were near one?

A lot. Let me give you a notional… I’ve got to be careful, I can’t speak too specifically, but one might imagine that you get a report from a pilot who says, “Lue, it’s really weird. I was flying and I got close to this thing and I came back home and it was like I got a sunburn. I was red for four days.”

Well, that’s a sign of radiation. That’s not a sunburn; it’s a radiation burn.

Then [a pilot] might say, if [they] had got a little closer, “Lue, I’m at the hospital. I’ve got symptoms that are indicative of microwave damage, meaning internal injuries, and even in my brain there’s some morphology there.”

Space-Time Warp

“And then you might get somebody who gets really close and says, “You know, Lue, it’s really bizarre. It felt like I was there for only five minutes, but when I looked at my watch 30 minutes went by, but I only used five minutes’ worth of fuel. How is that possible?”

Well, there’s a reason for that, we believe, and it probably has to do with warping of space-time. And the closer you get to one of these vehicles, the more you may begin to experience space-time relative to the vehicle and the environment.

Right now one of the leading theories out there is that someone has figured out a way to manipulate space-time and, in essence, master the idea of antigravity.

This man ran the Pentagon’s secretive UFO programme for a decade. We had some questions. GQ, 9 November, 2021.

Harold Puthoff

I have had the pleasure of talking on the phone with Lue Elizondo for a half hour or so, and of hosting Dr. Hal Putoff, Ph.D. in the Navy’s diving laboratory. Long ago, Puthoff directed programs on advanced sensing techniques (Remote Viewing) for the intelligence community. However, Hal’s Science Seminar at our Navy lab was on the potential harnessing of zero-point energy. Very strange stuff, that.

Lue is the most recognizable face of the former Pentagon UAP Investigation program. On the other hand, Hal is the brain that is trying to decipher the how of UAP propulsion systems. For years, those two men have worked closely together.

Harold (Hal) Puthoff, Ph.D., President & CEO at the Institute for Advanced Studies at Austin & EarthTech International, Inc.

Hal’s physics credentials are legion. For example, Hal has over 50 years of experience as a Research Scientist at General Electric, the NSA, Stanford University, Sperry & SRI International. He is an Advisor to NASA, the Department of Defense, and the Intelligence Community on leading-edge technologies and future technology trends. He holds patents in the laser, communications, and energy fields.

Because of Hal’s rich experience with classified projects, he remains hidden in the background regarding the journalistic how question of UAPs. But what Hal thinks undoubtedly rubs off on Lue, the cagey spokesman. So, what Lue says in unclassified publications like GQ has importance.

Space-Time Bubbles

Without a doubt, the esoteric theories of advanced physics, string theory, and minuscule curled “extra” dimensions present in a quantum world are inaccessible to our layman minds. However, if perchance a Navy pilot has reported something akin to what Elizondo reported regarding a close-up encounter with a UAP, then we have learned something of immense importance about space-time bubbles.

Space-time bubbles are something we can actually imagine, as long as we don’t get too far into the details. And that is a startling revelation.

No Gravitational Influence?

However, that revelation has embedded within it the most inscrutable of all mysteries.

The types of UAP motion witnessed by aircraft and shipboard sensing systems defy understanding. They have been observed to blink out and almost instantaneously appear 60 miles away. In conventional physics, that type of motion would generate acceleration forces (G-forces) that would destroy flesh and blood, and airframes. It is unsurvivable.

A series of Techno Thrillers collectively called the Jason Parker Trilogy, features a protagonist who travels in recovered alien spacecraft both undersea and in space. While virtually every other science fiction story ignores inertial forces, the JP Trilogy dutifully includes it. Inertia is an unavoidable fact of life in our dimensional universe.

The Jason Parker Trilogy

However, in a cosmos where space-time bubbles can pop into and out of our existence, the rules of physics must change. Quite possibly, interstellar travelers could be relaxing in their Stressless chairs while performing unimaginable aerobatics, from our perspective.

When Haseltine posits that the UAPs have no mass, he might be correct. They could be in a space-time bubble outside of our dimensional space, and therefore not influenced by our gravitational and inertial forces.

But there remains the nagging question that Elizondo and Puthoff, Haseltine and NASA, have not, and probably cannot, answer—How do you create a space-time bubble?

Professional Diving, Truth, and the Uncertainty Principle

Is anything known for sure?

Heisenberg’s Uncertainty Principle applied to quantum events avows that there is no certainty until you look. Well, this morning, I looked, and I’m just as confused as ever.

It was a chilly morning in late November. As we warmed up with coffee, I wondered how cold it was outside. So, in the modern style, my wife and I checked the Weather Channel on our phones. One indicated it was 47°F, but the other showed it was 48°F.

That can’t be, I said. So, with identical phones side by side, both tuned into Panama City Beach, Florida weather on the Weather Channel, one phone said it felt like 45°F, and the other said it felt like 43°F.

As Charlie Brown would say, “Good grief.”

Wanting to find some agreement among our devices, I checked a nested set of humidity and temperatures sensors grouped together in our kitchen. Humidity indicators are notoriously inaccurate, yet amazingly, the measured humidity was in reasonable agreement. But inside temperature varied from 70.3°F to 72.8°F.

According to Segal’s Law, “A man with a watch knows what time it is. A man with two watches is never sure.”

This aphorism is falsely attributed to Lee Segall of KIXL, now KGGR in Dallas. Regardless of the source, it is often repeated because it makes such good sense. If you multiply the number of devices three times, as above, the situation is no more precise. (But that’s where statistics comes in, I suppose.)

Giving up on simple things like local environmental parameters, I turned to the latest news on the VAERs update for the vaccines.

I wish I hadn’t. Yes, there is a chance you’ll be fine, but there’s also a small chance you’ll have heart problems and even a small chance you’ll die.

Frankly, my one-time shot at slot machines and the roulette table in Vegas did not end well. So, is there anything we know that can be guaranteed accurate?

Diving

I’ve spent a long Navy career in diving science, so I know there are serious certainties there. If you consume more air than is in your scuba tank, you’ll drown. If you stay down too long and surface too quickly, you’ll get the bends, aka decompression sickness.

But what if I use a decompression computer to plan my dive and follow its guidance to the letter? Unfortunately, there’s still a chance you’ll end up in a treatment chamber. Both people’s health and the water environment change constantly, and no decompression algorithm is perfect, or omniscient.

Undersea Oxygen Clinic, Tampa, Florida

From an engineer’s perspective, the tensile strength of a bolt is known within strict limits. If the force applied to that bolt exceeds its limits, then bad things might happen. Buildings might fall, or planes might crash. Or your muffler might fall off.

It’s hard to know what the effect of a broken bolt will be unless you understand precisely the function of that bolt. There is uncertainty in the outcome of a bolt breaking.

Uncertainty vexes some engineers to no end. I’ve watched them squirm as I reveal the role of statistics and probability in acceptance decisions about diving equipment. People are not bolts whose tensile and shear strength can be measured. As Heisenberg predicted (out of context), a dive outcome cannot be predicted with certainty.

Equipment Testing

The same thing applies to diving equipment. The Navy Experimental Diving Unit is entrusted with determining the safety and suitability of underwater breathing apparatus. Both physiologists and engineers envision a line in the sand for a given water depth and diver breathing rate.

If a UBA exceeds that line during testing, it should be rejected for military use. Right? After all, a limit is a limit.

Test and Evaluation Laboratory, Navy Experimental Diving Unit, Panama City, Florida. Photo by Stephen Frink.

Well, not exactly. When translating engineering limits into human terms, things get messy.  If a published limit is exceeded, just like taking the COVID vaccine, some people will fare well, while others may pass out. In other words, failure is classified as the probability of an untoward event where untoward translates to anything that threatens a diver or a diving mission.

For any given dive, and any given diver, the probability of a dive failure cannot be known precisely. Dive failure, like decompression sickness, is probabilistic.

One type of untoward event: Ice inside a second-stage scuba regulator.

To illustrate, the following table and text are from NEDU Technical Report 16-04, Physiological Event Prediction in Evaluations of Underwater Breathing Apparatus, October 2016.

Usually, a UBA evaluated at NEDU is suitable for most diving depths and any foreseeable work/ventilation rate, as shown in Table 1.

The only time that limits were exceeded was at the greatest depth and ventilation rate.

But what if the data had revealed a slightly larger “out of limits” region, as in the next table? What decision regarding safety would then be made?

Hypothetical Test Data

In this hypothetical case, human judgment is required. It is not sufficient to declare the diving equipment unsafe for use. It simply means divers need to pace themselves when working and breathing hard near a depth of 200 feet. Reducing their workload enough to slow their breathing to 62 liters per minute or less (still a high ventilation rate) is a safe way to keep the UBA within limits.  

This is nothing new. Every salvage diver knows to occasionally interrupt hard work periods with periods of rest. Catching your breath is kind of important.

Limits are not absolute

As a person with too many watches, or thermometers can attest, you can’t be sure what all the various goal numbers and limit numbers mean. Instead, collectively they should be used as a guide to safe diving.

Hanging on the umbilical in a KM 37.

Whether you’re a sport diver or professional, if an underwater breathing apparatus is functioning normally but doesn’t meet all of the EU (EN250) or U.S. Navy engineering limits under all possible testing conditions, that doesn’t mean it’s not a useful piece of diving gear. You just have to use it judiciously. After all, good human judgment is always required for safely operating life support equipment.

It is a wise diver who remains mindful of their life support system’s limitations and plans their dive to stay within those limitations. That way, the probability of experiencing an untoward event is minimized.

My Weird, Spooky Body

My body has a few unusual traits, or anomalies if you will. For most of those anomalies, science has attached a name. But those traits are still strange enough to make them worth describing.

And a couple of them are, well, just plain weird.

Sun Sneeze.

Let’s start with an easy one. The so-called photic sneeze reflex used to be most noticeable when my brother and I would leave a dark movie theater after a matinee and open the doors to bright sunshine. Instantly, I’d feel a slight tickle in my nose, which would be immediately followed by a sneeze.

What the heck! Sunlight makes me sneeze?

Well, I can assure you that as a Sunshine State resident, not all sun exposure makes me sneeze. It’s only an abrupt transition from dark to full brightness. It comes on faster than a transition lens can transition.

While most bodily adaptations and reflexes have conveyed to humans some survival value, I can’t see that this one does. Let’s suppose that a distant ancestor of mine might have been stalked by a Sabre-tooth tiger. To elude it, my hominid homey disappears into a dark cave waiting for the tiger to pass by. He tries hard to make no sound that would alert the big cat to his presence. Then, when he thinks the coast is clear, my ancestor sticks his head out into the sun outside the cave, and promptly sneezes.

So, I see absolutely no adaptive benefit to the so-called sun sneeze.

Just to show that scientists do have a sense of humor, according to Wikipedia, the photic sneeze reflex is also known as Autosomal Dominant Compelling Helio-Ophthalmic Outburst(ACHOO) syndrome, or photosneezia.

This is a joke, right?

Well, apparently not. Google it if you’re in doubt.

“Outburst (ACHOO) syndrome or photosneezia…colloquially called sun sneezing, is a reflex condition that causes sneezing in response to numerous stimuli, such as looking at bright lights…the condition affects 18–35% of the world’s population.” 

So, statistically, quite a few readers should have the same response.

Quoting further, “The condition often occurs within families, and it has been suggested that light-induced sneezing is a heritable, autosomal-dominant trait. A 2010 study demonstrated a correlation between photic sneezing and a single-nucleotide polymorphism on chromosome 2.”

Which is science talk meaning I picked it up from one of my parents. Oddly, I don’t remember my parents ever sneezing. But then, that’s not the type of thing one remembers.

Salt Cough

Speaking of useless human reactions, my mouth is an extremely sensitive salt detector. Although I do love salt and have occasionally been caught snacking on a few unhealthy potato chips for their salt content, they do make me cough.

Which, of course, means my wife catches me every time. My cough betrays me.

As for the cause of a salt cough, my Googling has returned essentially nothing. For instance, someone responded to a Quora inquiry by stating, “You must be sensitive to salt.”

Well, duh. Brilliant non-answer.

Now, for more weirdness that lacks a good explanation.

Itchy Spot

My dermatologist explained that the proper medical term for an itchy spot in a well-defined area below my left scapula is Notalgia paresthetica. The cause and explanation for it are not clear. Still, once again, roughly 20% of the adult population might be similarly affected at one time or another.

Not surprisingly, my dermatologist gave me a Botox injection to deaden the spot. Well, I appreciate the effort, Doctor, but it didn’t work. In fact, some research from 2014 has found limited or no improvement from using Botox.”

It’s important to note that the study only included 5 participants. So, I’m thinking about writing the authors of that study to ask them to add me to their list.

I know my brother was so affected because I remember him rubbing his back against the edge of a door frame. From my own experimentation, that helps a little but is short-lived.

For me, after a shower, when my back is exposed to drafts, the itch becomes acute enough that I reach for the best back scratcher I’ve ever found. It’s called a Cactus Scratcher.

A couple of seconds of gentle scratching relieves the itch.

(Caution: although it may feel good at the time, excess scratching damages the skin and will do more harm than good.)

(Note: I have no association with the creators of the Cactus Scratcher. I simply love their product.)

The Marvels of Near Sightedness

For those who temporarily remove their glasses and descend into the poor-vision world, some optical marvels await you. You can see things normal-sighted people can’t.

I discovered this in my youth in Kansas when I would make long runs during the cool of a summer’s night. Stopping to wipe sweat from my brow, I removed my glasses and noticed the most intricate patterns in the distorted light of street lamps.

In the absence of my eye correction (my vision was measured as 20/400+), I would have expected the light from the tall lamp to be little more than a fuzzy halo, like everything else I saw. But instead, I saw intricate patterns in the light. There was amazing geometrical complexity and symmetry in what I saw, something that, to my knowledge, had never been reported. The patterns were beautiful.

So how could that occur, when in fact, the definition of myopia is that light focuses too far in front of the fovea? Beyond the focal point of the lens, the light expands into a fuzzy spot. How could a fuzzy beam of light from a street light reveal a beautifully detailed and symmetrical image?

Photographers are aware of symmetrical and surprisingly sharp images that appear in out-of-focus images of sources of light. That optical phenomenon, called Bokeh,  is often altered by the properties of both the camera lens and the geometry of the aperture or iris. It can be “good” Bokeh, enhancing the aesthetic of the image, or “bad” Bokeh, detracting from the appeal of the image.

An example of the bokeh produced by the Canon 85 mm prime f/1.8 lens. The polygonal shapes are due to the 8-bladed aperture diaphragm being slightly closed. At its full aperture (f/1.8) these shapes would be smooth and not polygonal. By JWCreations – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5462407.

Reasonably, the human lens and iris might contribute to a similar phenomenon, in nature, not artificially in a camera.

However, that does not explain the geometrical patterns I saw in the street lights. Fortuitously, but decades later, the research group at the MIT Media Lab discovered that very small patterns can be used to transmit information. But unlike the microdots so famously used by spies, these patterns can be made visible by setting a camera lens to an infinity focus. Ironically, the out-of-focus view of the dot reveals the embedded pattern.

Such a method of data encryption and revelation is called a Bokode, an invented word being a portmanteau of the Japanese word bokeh and the English word bar code.

A short MIT-produced video about Bokodes.

Similarly, I wonder if a pattern embedded in the lens of a vintage street light would be revealed by the out-of-focus image captured by the retina of a myopic young man. 

If so, that might explain the intricate detail I saw when looking at the fuzzy image of a street light thirty or so feet away.

Of all my physical anomalies, this was the spooky one. Like that famous line in The Sixth Sense, I can “see things” normal people can’t.

Cole Sear, played by Haley Joel Osment, in The Sixth Sense.

A Non-Microscope Microscope

While the previous bodily trait was a little spooky, the next one is just weird.

A year or so after the street light discovery, I was sitting at my desk in a dorm room at Georgia Tech. My parents had bought me a Tensor lamp to study by. The bulb was small but put out a high-intensity light, unexpected for the bulb’s size.

At the time, the Tensor lamp was the newest thing in lighting. The light had been designed for medical and dental applications. Still, a year before I started college, it was being sold to the public as a sleek, modern-looking, compact desk lamp.

I appreciated that lamp because, in a shared dorm room, size does matter. Smaller is better.

One night during my studies, and being as easily distracted as a cat by a laser pointer, I noticed that the intense spot of light from the Tensor lamp was reflecting off the convex surface of the cap of a Bic pen. 

Mindful of discovering the intricate patterns in the street lamp in Kansas, and most importantly being alone in the room, curiosity overcame me. I set my glasses on my desk and looked at the reflected light.

I saw nothing but the reflected light. Undeterred, I moved the pen cap closer to my eye, thus expanding the relative size of the reflected spot of light. I could then see something, but it wasn’t a clear image like the street light aberration. So, I moved the cap still nearer, until the cap was a few millimeters from my cornea. I should not have been able to focus on anything that perilously close to my eye.

But as they say in France, Voila! Now I could clearly see a microscopic view of the surface of the curved cap. From a normal distance, the plastic cap was smooth, but in my new microscopic vision, the surface was slightly irregular.

To confirm that what I saw was not an illusion, I scratched the plastic cap with a straight pin. After viewing the cap again as I had before, I could clearly see a plastic canyon where I had just gouged the surface.

I had inadvertently discovered a nonmechanical inspection microscope!

About that time, my roommate opened the door and froze. “Are you trying to put your eye out?”

Not surprisingly, roomie did not share my excitement in this new discovery in optical physics. Nor did a physics professor I later queried about the observation. He had no clue about what I had seen, and probably thought I was a little reckless to have tried that experiment.

Of course, I wondered about the commercialization and patenting potential of my discovery. But I never found an explanation for the physics, a requirement for a patent. And besides, there was no hardware I could sell. It was simply yet another “feature” of myopia. All I needed to conjure the effect was to be very nearsighted, own a Tensor lamp, have a supply of BIC pens, and be willing to open myself up to ridicule.

I suspect that combination is somewhat rare.

I am tempted to think that what I was seeing on that BIC cap was somehow related to MIT’s Bokodes. The reflected light was intense, and there was a pattern of sorts on the cap. And certainly, my view of that reflected light spot was way out of focus.

But without a fair amount of experimentation in an optics laboratory (which I don’t have access to), I can neither support nor dismiss the Bokode hypothesis.

In other words, I’m not sure how it happens. If any of you readers figure out how that phenomenon worked, please let me know. I will be grateful, and you will have proven yourself smarter than at least one Georgia Tech physics professor.

Confessions of a UFO Skeptic

Some lines are risky to cross. The line separating fact from fantasy is one such line.

What is remarkable to me about the U.S. government’s recent disclosure of the reality of UFOs, or UAPs, is that even those skeptics who have a reputation for rolling their eyes and bursting forth with ridicule have had to face the truth. Too many people are righteously aware, and claiming they aren’t, doesn’t work anymore. What many smart people have long considered fantasy, is now known to be fact. Confusing fact, perhaps, but fact nevertheless.

This scientist-writer believes that closing your mind to possibilities does nothing more than handicap your consciousness. If you refuse to peer over the boundary of your perceived reality, you’ll limit your awareness. And oh, what interesting things you’ll miss.  

Recently I was surprised to read an open apology from a renowned skeptic of the UFO phenomena, a Harvard-trained mathematical physicist and cultural commentator, Eric Weinstein.

Recently, David Bates gave the tweets from Eric Weinstein room on his pages. Not only was Weinstein brutally honest, but I found his challenge to closed-minded scientists especially refreshing.

Weinstein’s Tweets

From Weinstein’s own tweets, Bates quoted the following.

To all the UFO people who were getting it right: I blew it. I thought you were bored, easily convinced, read too much sci-fi as kids, were easily taken in. I thought there was no way this could ambiguously exist in a world flooded with sensors. I thought you were not getting it.

I am very late to your party and even having gotten the report mostly right, it has been exceptionally unpleasant to get in front of it by even a few months. I can only imagine how it feels after the many years the US has gaslight you all while knowing you were not wrong.

A lot of UFO people are nutty. But you the careful community that called balls and strikes as best you could with limited information deserve not only rehabilitation in the minds of the public, but some official recognition that you are to be listened to in the future. Thank you.

I believe you now when you say that there is even much more high quality data available but that it has not been released. At a personal level: You were right, I was wrong. Thanks for letting me join you at the ‘last minute’ in the few months before the report. I’ll listen more.

I also wanted to say to the non-ufo community that whatever I got right largely didn’t come from me. It came from patriots, fellow scientists & others who were not taken in the way I was. All I did was a bit of filtering and after-market analysis given the gravity of the issue.

According to Bates, Weinstein followed up a few hours later.

It’s totally irresponsible for any scientist to refuse to investigate UAP after this report with a full and unpruned decision tree at her side. That includes considering the total incompetence of the defense department, *aliens*, spoofing by enemies and UFO political economy.

And US scientists who refuse to take this seriously as per the above tweet are neglecting and/or turning their back on our national and international security responsibilities given this report. That is my belief. Full stop.

Thank you, David Bates, for making these tweets accessible.

Discover More

Seeking an exhaustively compiled account of a particular class of large UFOs, the Triangles? Look no further than the investigative writings of David Marler. In my opinion, as current UFO investigators go, he is the most careful and detailed of them all.  

From the cover of Triangular UFOs: An Estimate of the Situation.

Weinstein photo credit: By Rebel Wisdom, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=76267996

Science Fiction Writers and the New UFO Report

I thought the jig was up when I heard the top U.S. Intelligence Agency was releasing what it knew about UFOs. (See link at the bottom of this post.)

Who would want to read a science fiction novel about UFOs and aliens when the truth is—as they say—stranger than fiction?

What would happen to all those imagined UFOs that slice through water as easily as air? What about spaceships that are massive quantum computers that sense, think and plot the safest course through a universe littered with obstacles both large and small?

What about ships powered by the free energy of the cosmos, steered by the photonic vibrations of colored lights modulating the propulsive energy at the core of the cosmic vacuum?

What would be the fun in imagining aquatic species able to tolerate high pressures but unable to survive the toxic oxygen in our atmosphere? Where would the mystery go once we knew the truth?

 What could inspire awe in reading about humans working with strange creatures who teach us to genetically engineer a new breed of humans to survive coming cosmic cataclysms?

What is the use in imagining, once you know the truth?

Departing for Mars. Illustration from Atmosphere, Book 3 of the Jason Parker Trilogy.

Well, as we now know, science fiction writers needn’t worry. Yes, the U.S. military finally admitted that UFOs exist, which is a vast improvement in government transparency. And, let’s admit it, the reality of UFOs has been one of the worst kept secrets of all time. The darn things keep showing up at the strangest times, sometimes far away, but sometimes incredibly close.

The luckiest humans, those who win the UFO reveal lottery with a closeup view of the craft, have their lives changed forever. This I know. And the number of such human observers are legion.

For reasons known only to the government, their admission of UFOs is not accompanied by the sort of detail for which most UFO aficionados were hoping. But frankly, that is likely a deliberate ploy for reasons of national security. I truly believe, and fully support, the continued need for secrecy.

And because of that secrecy, science fiction writers are still free to imagine what they will. After all, fantasy might be the best way to sow awareness of things we cannot imagine, outside of fiction.

But there are some things that science fiction writers like myself find hard to comprehend. The questions I pose here are ones that in my opinion are of much greater importance than the reality of UFOs, or even ETs from distant star systems.

Frequently, nonscientists attempt to explain the weird nature of some UFO sightings by supposing the craft appear from some bubble of an extradimensional universe. The craft and their supposed inhabitants are perhaps not from a portion of our universe far, far away, but rather they are in fact—right here. Right here as in right next door in a higher dimensional universe, or multiverse!

I repeat, I have heard such things from nonscientists. So, what do scientists think?

With few exceptions, they ignore it. Even the multiverse-believing cosmologists don’t yet have the tools to detect unseen universes. Not seeing is not believing, although to be fair, they may spend a lot of time thinking about it.

I would agree that much of the popular writings on the subject of unreachable dimensions are pseudoscience, or less politely, poppycock. Except for the fact that Einstein once said, “It is entirely possible that behind the perception of our senses, worlds are hidden of which we are unaware.”

So, as a scientist and writer, I hold fast to the fact that long after we know that three-dimensional spacecraft and their alien crews exist, we still will not understand higher dimensional universes. Are there hidden worlds there, as wondered by Einstein, populated with sentient beings?

I wish I knew for sure. I would dearly love to possess a higher dimensional container, a sort of a stripped-down, dumb version of Dr. Who’s Tardis. That way I could discard accumulated junk and never see it again. And I’d never get charged disposal fees.

Free energy would be life changing, but free junk disposal would be the icing on the cake.

Top image: A scene from Atmosphere, book 3 of the Jason Parker Trilogy. (Copyright, 2020, 2021)

Here’s the link to the Preliminary Assessment from the Office of the Director of National Intelligence. (For Jason Parker readers, that’s the same office that fictionally hired Laura Smith to be their Subject Matter Expert on ET Affairs.)

Nuclear Incident at Georgia Tech

Large scale nuclear accidents like those at Chernobyl and Fukushima are environmental disasters which grab the headlines. But lesser accidents do occur, just as in any industrial facility. I was involved in one such incident.

From the mid-sixties to the mid-nineties, Georgia Tech had a research reactor which served a multitude of research purposes. It also gave Nuclear Engineering students a hands-on experience with a working nuclear reactor.

The Frank H. Neely Nuclear Research Center, contained a 5-megawatt heavy-water (D2O) cooled reactor located on the Georgia Tech campus.

The Georgia Tech Nuclear Reactor and Research Center

In the late 60s, I was a graduate student in the Georgia Tech Department of Biology. I was working for a professor who had an interest in manganese and bacteria. One of his projects was using neutron activation of the manganese ions found in Atlanta’s drinking water supply, Lake Lanier. Elevated manganese levels in water is an indicator of pollution. 

After driving to Lake Lanier and launching a small boat, another graduate student and I would pump lake water from 100-feet down up into water sampling jugs on the boat. Our most important sampling site was just offshore a water treatment plant, the currently named Shoal Creek Filter Plant. That plant was less than two miles from the Buford Dam, so the water was reliably deep.

Buford Dam at Lake Lanier, https://saportareport.com/metro-atlantas-drought-far-dust-bowl-far-healthy/columnists/david/

One day, the 100-foot-long sampling line disconnected from its reel and disappeared overboard. Without thinking, I dived over the side of the boat with my glasses and billfold, and swam down after the disappearing line. The yellow-green light was getting dimmer every foot I descended.

I was probably twenty feet down when I caught a blurry sight of the barely visible line sinking rapidly through the water.

As I rose back to the boat with the line in my grasp, my crewmate gave me a look of “What the (expletive deleted) just happened?” He had been looking away when I dived overboard, severely rocking the boat. One second, I was there, and the next second I was gone, almost throwing him into the lake in the process.

That was not the last time he would be surprised, as you will read shortly.

Miraculously, I did not lose my glasses, but all my billfold photos were a total loss. But I had saved the research equipment! 

Back at the Frank H. Neely Nuclear Research Center, my crewmate and I would send aliquots of the water into the core of the reactor using an air-driven pneumatic system called a “rabbit.”  Once in the reactor core, the water sample was bombarded by a dense neutron flux, for a predetermined amount of time. 

The floor of the reactor containment building during our time there. The control room is mid-photo.

Georgia Tech reactor control room. We technicians could look but couldn’t touch.

Once the rabbit system pulled the sample out of the core, the sample was measured by Geiger counter to determine if it was safe to approach.

Neutron bombardment produced radioactive isotopes of manganese, converting Mn55 into Mn56. Mn56 has an ideal half-life of 2.6 hours and emits gamma rays at 846.8 keV. Manganese is easy to detect with gamma spectroscopy. 

Due to the low level of manganese in the fresh water samples, the Geiger counter never indicated the sample was “hot” after its trip to nuclear hell.

Neutron Activation and radioactive decay. Element X has a mass A and charge Z. Absorption of a neutron increases A by 1. Beta particles can have either a negative charge (like electrons) or a positive charge (positrons) so the result of beta decay can yield a net positive or negative charge.
 https://nmi3.eu/neutron-research/techniques-for-/chemical-analysis.html

We prepared the lake water samples in a clean room environment. That is also where we returned the newly radioactive sample, transferring it to a sample cell placed in the lead-lined spectrometer. Of course, we always wore full isotope protection (disposable gloves, gowns and masks.)

Modern day laboratory equipment for determination of γ-radiation spectrum with a scintillation counter. The output from the scintillation counter goes to a Multichannel Analyzer which processes and formats the data. By Manticorp – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17598452

After gamma ray measurements were taken, the radioactive samples were placed in lead-lined cavities for disposal by reactor staff. 

Our work progressed without incident until the professor asked us to activate a sample of saltwater. Neutron activation of Cl35, the natural form of chlorine, produces Cl36, with a half-life of 301,000 years. 

We noted that as the rabbit returned with its sample of saltwater from its trip into the reactor core, the sample was extremely hot (radioactive), due no doubt to the high concentration of chlorine in salt water. After letting it cool a bit (some chlorine isotopes decay quickly), we performed our usual sample transfer and measurements.

Cl36 is a weak gamma emitter, but we had a hot enough dose to pick it up on the gamma spectrometer. The primary decay mechanism for Cl36 is through low-energy beta particles. 

The radiation doses and half-lives had always been low and short for the manganese fresh water samples, and thus we were not in the habit of placing our hands and feet through a radiation detector prior to leaving the reactor research building. That dosimeter was intended for “hot” work. 

As usual, it was late in the day when we finished our work, and few people remained in the building. Before exiting the building after our seawater work, we passed by the usually ignored detector. 

But that day, I turned around and said, “Let’s check ourselves, just to be sure.” 

I was clean, as I had expected. But as my colleague put his hands and feet into the device, screeching alarms and flashing red lights stunned us. As we southerners say, it caused a commotion.

I had heard that nuclear danger alarm only once before, without knowing the cause of it. But now, we were the center of attention. The few people remaining in the building surrounded us within seconds, or so it seemed.  Apparently, running towards danger is for all kinds of first responders. 

After the staff carefully examined our discarded gloves, masks and garments, they discovered that one of the gloves had a small tear in the right-hand thumb. That small tear was all it took to contaminate my friend. 

It was late at night before we were cleared to leave, and then only with extensive washing of my colleague’s right hand. The radiation safety officer wrapped a thick layer of gauze around the offending thumb, and securely taped it. And then he got to work on a lot of paperwork. 

Unlike the Mn isotopes we normally worked with, the Cl36 isotope would not decay for many human lifetimes. So, scrubbing and dilution was the only solution. 

The thumb was heavily bandaged because the only risk was to the student’s new baby. Beta particles, essentially electrons, cannot penetrate deeply to vital organs, so Cl36 residue was not as much of a concern as would be gamma emitters. However, if the baby had sucked on the father’s thumb, the way teething babies do, the Cl36 isotope would have been ingested. And beta radiation occurring internally can be a health risk. 

https://weillcornellgucancer.org/2017/04/12/using-alpha-and-beta-radioisotopes-to-kill-cancer-cells/


And to think, we almost let my friend go straight home to take over baby duty. 

My fellow student was warned to keep his distance from his baby, and wash his hands thoroughly several times a day, rewrapping his thumb with fresh gauze after every wash. After a week of that repetitive washing routine, it would likely be safe for him to cuddle his baby girl once again, after one last Geiger Counter check. 

In the meantime, he was excused from diaper duty! 

This type of contamination incident may be more common than you think. Fortunately, it did not equate to a calamity. But it could have been a calamity for that little girl and her family had she ingested radioactive chlorine atoms.

Those dealing with radioactive materials, high pressure, dangerous chemicals, fires, and carrier flight decks, to name just a few hazards, know that personal disaster is only a misstep away. In spite of training, humans do make mistakes. But fortunately, this mistake was caught in the nick of time.

Radioisotope image credit: Foro Nuclear



Maintaining Your Respiratory Reserve

The following is a reprint from InDepth: Digital Scuba Diving Magazine by Global Underwater Explorers.

Published on September 6, 2019             By InDepth

by John Clarke

JJ on his JJ.” Photo by Andreas Hagberg.

Just like skeletal muscles, respiratory muscles have a limited ability to respond to respiratory loads. An excellent example of this is a person’s inability to breathe through an overly long snorkel (Figure 1.) Our respiratory muscles simply aren’t strong enough to overcome the pressure difference between water depth and the surface.

This doesn’t work. Her respiratory muscles are not strong enough.
Illustration by Cameron Cottrill.

The primary respiratory muscle is the diaphragm, (the brown organ lying below the lungs in Figure 2.) The diaphragm is designed for low-intensity work maintained 24/7 for the entirety of your life.

Like the heart muscle, its specialty is endurance. When called upon to maximally perform,  the diaphragm needs assistance.

That assistance is provided by the accessory respiratory muscles, primarily the intercostal muscles linking the ribs within the rib cage.

The human diaphragm separating the lungs from the abdominal cavity. Graphic by John Clarke.

Unless you’re reading this while running on a treadmill, your body is probably idling. Your heart is beating rhythmically, your diaphragm is methodically contracting and relaxing. But, if some dire event were to happen, you would be primed for action. If you needed to react to an emergency, your heart and lungs would race at full speed.

The difference between idling and full-speed capability is called physiological reserve, which in turn is divided into its components; cardiac, muscular, and ventilatory reserve. As drivers, pilots, and boat captains will attest, it’s always good to have fuel reserves. Likewise, physiological reserve is good to have in abundance.

The Dive

The following is an imaginary tale of a young, blond-haired hipster drawn to the Red Sea for a deep dive. He chose to dive on the wall at Ras Mohammed on the Eastern Shore of the Sinai, which descends quickly down to a thousand feet and beyond. That was his target—1,000 feet.

The previous year he bought a rebreather so gas usage should not be a problem for his deep dive. He also sprang for the cost of helium-oxygen diluent. Trimix would have been cheaper, but he spared no expense. Nothing but the best. To that end, he used loose-fill, fine grain Sodalime in his CO2 scrubber canister.

These were his thoughts as he descended.

Free-falling at three hundred feet. Never been this deep before. The water’s getting cold, so the warm gas from the canister feels good.

800 feet. Wow, the gas is thicker now.

When he reached the bottom, he realized something wasn’t right. He sucked harder and harder, feeling his full face mask collapsing around his face with each inhalation. He was “sucking rubber,” feeling like he was running out of gas, but his diluent pressure gage still read 1800 psi.

Unconsciously, he compensated for the respiratory load by slowing his breathing—easing his discomfort. Concerned, he briefly switched to open circuit bailout gas, but that didn’t feel any better. In fact, it was worse, so he switched back to the bag.

Surprisingly, he couldn’t get off the bottom. In fact, he was slipping further downslope. He needed to drop weights, but they were integrated. He fumbled with his vest, trying to remember how to release the weights, but he couldn’t work it out.

He found the pony bottle to inflate his integrated BC, but after a second’s spit of air, it stopped filling. He would have to swim off the bottom. As he struggled to swim upwards in the darkness, and without bubbles to guide him, he wasn’t sure which way was up.

His heart was beating at its maximum rate, trying to force blood through his lungs, but he couldn’t force enough gas in and out of his lungs to clear his bloodstream of its increasingly toxic CO2 load. The build-up of CO2 in the arterial blood was clouding his thinking. The CO2 was making him want to breathe harder, but he couldn’t. The feeling of breathlessness—and impending doom—was overwhelming.

————

The accident investigation on the equipment was inconclusive. The dive computer had flooded, but that was irrelevant. Surface pre-dive checks were passed. The rebreather seemed to function normally when tested in a swimming pool. The investigators convinced a Navy laboratory to press the rebreather down to 1,000 feet, but nothing abnormal was found other than a slight elevation of controlled PO2.

The Analysis

An asthma attack can kill by narrowing the airways in the lung, making the person suffering the attack feel like they’re sucking air through a clogged straw.

A healthy diver doesn’t have airways that constrict, but gas density increases with depth, causing the same effect as a narrowed airway. It becomes increasingly difficult to breathe as depth increases. A previous InDepth blog post on gas density discusses this subject.

Normal human airways compared to airways during an asthma attack. Graphic courtesy of Asthma and Allergy Foundation of America.

If the strength of respiratory muscles is finite, just as it is for all muscles, then any load placed on those muscles will eat away a diver’s “respiratory reserve.” From the diaphragm’s perspective, the total loading it encounters is divided between that internal to the diver and that external to the diver. As gas density increases, internal loading increases. A rebreather is external to the body, so flow resistance through a rebreather adds to the total load placed on the respiratory muscles. If the internal resistance load increases a lot, as it does at great depth, there is very little reserve left for external resistance, like that of a rebreather.

In this fictional tale of a hapless diver, he needlessly added respiratory resistance by using fine-grain Sodalime in his scrubber canister. Compared to large grain Sodalime, such as Sofnolime 408, fine-grain absorbent adds scrubber duration, but it also increases breathing resistance. It thus cut into the diver’s ventilatory reserve.

This fictional diver exceeded his physiological reserves by,

  1. not understanding the effect of dense gas on the “work of breathing,”
  2. not understanding the limitation of his respiratory muscles, and
  3. by not realizing the “best” Sodalime for dive duration was not the best for breathing resistance.

He also didn’t realize that a rebreather scrubber might remove all CO2 from the expired gas passing through it, but it is ventilation (breathing) that eliminates the body’s CO2 from the diver’s bloodstream. Once CO2 intoxication begins, cognitive and muscular ability quickly decline to the point where self-rescue may be impossible.

Lessons from The U.S. Navy

Considering the seriousness of the topic, it is worthwhile to review the following figures prepared for the U.S. Navy.

First, we define peak-to-peak mouth pressure, a measure of the pressure exerted by a working diver breathing through the external resistance of a rebreather. Total respiratory resistance for a diver comes in two parts: internal and external. In the following figures, those resistances in the upper airways are symbolized by a small opening, and in the external breathing apparatus, by a long, narrow opening representing a UBA attached to the diver’s mouth.

High external resistance. In this case, the difference between mouth pressure and ambient water pressure is called ΔP1 Credit with modifcation: “Direct measurement of pressures involved in vocal exercises using semi-occluded vocal tracts”.
Low external resistance. The difference between mouth pressure and ambient water pressure is called ΔP2. Credit with modification: “Direct measurement of pressures involved in vocal exercises using semi-occluded vocal tracts”.
Mouth pressure waveforms ΔP1 and ΔP2 during breathing with high (P1) and low (P2) external resistance.

This author reviewed over 250 dives by Navy divers at the Naval Medical Research Institute and the Navy Experimental Diving Unit. These were working dives involving strenuous exercise at simulated depths down to 1500 feet seawater, using gas mixtures ranging from air to nitrox and heliox. Gas densities ranged from about 1 gram per liter (g/L) (air at the surface) to over 8 g/L. Each dive was composed of a team of divers, so each plotted data point had more than one man-dive result included. An “eventful” dive was one where a diver stopped work due to loss of consciousness, or respiratory distress (“dyspnea” in medical terminology.) They were marked as red in the following figure. Uneventful dives were marked in black.

Using a statistical technique called maximum likelihood, the data revealed a sloping line marking a boundary between eventful and uneventful dives.

Peak-to-peak mouth pressure and gas density conspire to increase a diver’s risk of an “event” during a dive.

The fact that the zero-incidence line sloped downward illustrates the fact that the higher the gas density, the greater the respiratory load imposed on a diver by both internal and external (UBA) resistance. The higher that load, the lower the diver’s tolerance to high respiratory pressures.

By measuring peak-to-peak mouth pressures, we are witnessing the effect of UBA flow resistance at high workloads. It does not reveal the flow resistance internal to the body. However, when gas density increases, internal resistance must also increase.

The interrupted lines in the figure illustrate lines of estimated equal probability of an event. The higher the peak-to- peak pressure for a given gas density, the higher the probability of an eventful dive.

Figure 7 suggests that at a gas density of over 8 grams per liter, practical work would be impossible. The only way to make it possible would be to reduce gas density by substituting helium for nitrogen, or substituting hydrogen for helium, and then doing as little work as possible to keep ΔP low.

For our fictional 1,000 foot diver, the gas density would have been between 6 and 7 grams per L. Using a rebreather, there would be virtually no physiological reserve at the bottom. Moderate work against the high breathing resistance at depth would be very likely to result in an “eventful” dive.

Image Citation for medical graphics: Robieux C, Galant C, Lagier A, Legou T, Giovanni A. Direct measurement of pressures involved in vocal exercises using semi-occluded vocal tracts. Logoped Phoniatr Vocol. 2015 Oct;40(3):106-12. doi: 10.3109/14015439.2014.902496. Epub 2014 May 21. PMID: 24850270.

John Clarke, also known as John R. Clarke, Ph.D., is a Navy diving researcher in physiology and physical science. Clarke was an early graduate of the Navy’s Scientist in the Sea Program. During his forty-year government career, he conducted physiological research on numerous experimental saturation dives. Two dives were to a pressure equivalent to 1500 fsw.

For twenty- eight years he was the Scientific Director of the Navy Experimental Diving Unit.

Clarke has authored a technothriller-science fiction series called the Jason Parker Trilogy. All three volumes, Middle Waters, Triangle, and Atmosphere, feature saturation diving from depths of 100 feet to 2,500 feet. The deepest dives involve hydreliox, a mixture of helium, hydrogen and oxygen. UFOs, aliens, and an uncaring cosmos lay the framework for political and human intrigue both on and off-planet.

Although now retired, Clarke has worked for NEDU as a Scientist Emeritus. He now runs a consulting company, Clarke Life Support Consulting, LLC. He helps various companies, when he isn’t writing about diving, aviation, and space. His websites are www.johnclarkeonline.com and www.jasonparkertrilogy.com. His thriller series is available at Amazon and Barnes & Noble.

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