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.


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.


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.


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.


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.

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,

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.


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.


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.