Sunray, Texas: July 29, 1956

At a 170,000-barrels-per-day refinery near Sunray, Texas, the newest of twofire stations is designated "Station 19." It signifies the number who died more than half a century ago in a tragedy that ranks only three places behind the World TradeCenter as killing the largest number of American firefighters in a single incident.

On a fatal Sunday morning in July 1956, a 15,000-barrel pumpkin-shaped spheroid tank containing about 500,000 gallons of mixed pentane and hexane caught fire.The plant fire brigade and volunteers from the nearby Texas panhandle communities of Sunray and Dumas responded to what evolved into a combination ground and vent fire.

"Obviously, there wasn't much or certainly not enough known about BLEVEs (boiling liquid expanding vapor explosions) back then," said refinery Fire Chief Mike Roberts in 2006. "While these gentlemen were actively fighting the groundfire and trying to control flame impingement, the spheroid BLEVEed."

At age 13, Ken Floyd witnessed the explosion from a vantage point so close he suffered severe burns. Yet, despite his vivid recollection of the actual event, the image irreparably seared into his memory was when he and the other casualties arrived at the local hospital.

"As the patients entered the hospital, they each took off their scorched shirts,"Floyd said. "They tossed them in a pile by the door."

Paying tribute did not end with the station's name. In April 2006, the refinery opened its doors to the public to dedicate the new station and commemorate the 50th anniversary of the disaster. Nearly 600 people attended the ceremonies, including four surviving spouses and other relatives of the firefighters killed. The experience was more joyous than tearful, Roberts said.

"I felt like it probably was going to be hard on the widows, but I've never seen more smiles or gotten more hugs and thanks in my life," Roberts said. "I think it actually gave them some kind of closure."

What came to be known as the Sunray disaster remains relatively unheard of today. Before the refinery ceremonies, the outstanding memorial to the event wasa monument to volunteer firefighters on the grounds of the state capitol in Austin that lists the 11 Sunray and Dumas firefighter fatalities beside those from a morefamous Texas fire disaster — Texas City in 1947.

That memorial does not list the refinery employees who were lost battling the blaze.

What we know for certain about that morning on July 29 is that theterrain and design proved to be the critical factors. First, flammable hexane and pentane vapors escaped from the spheroid designated as No. 199. An article in the Oil and Gas Journal speculated about a line break, pump leak or even the popoff vents at the top of the tank.

"The first part is pretty unclear," Roberts said. "Back then, all spheroids vented to the atmosphere. Anyway, the relief valve released and when it did it turned pentane loose to the ground."

In 1956, the refinery was only a 20,000-barrels-per-day facility, situated 11 milesfrom Dumas, population 8,000, and seven miles from Sunray, population 1,500. TheNational Fire Protection Association publication NFPA Quarterly reported thatthe tank farm was well spaced, with individual dikes for the various floating roof,cone roof, spheroid and noded spheroid tanks. Contents ranged from crude oil tofinished products. A highway bordered the tank farm on the south side. Nearly 500feet separated the highway from the refinery process area.

Unfortunately, that 500 feet separation was on a slight downhill grade.

"The vapors of both pentane and hexane are considerably heavier than air," the NFPA article states. "With air equaling one, the vapor density of pentane is 2.49 and for hexane, 2.975."

A light southwest wind, unusually mild for the region, helped the vapors along. It blew toward the process area, specifically an asphalt tank about 350 feet away under which a small fire was kept. At about 5:45 a.m. vapors ignited, then flashed Sunday starts early in most Bible Belt Texas towns. However, residents of Dumas were concerned about more than getting ready for church that morning. Sirens began wailing in the distance and smoke rose in the sky north of town in the direction of several industrial facilities.

Floyd remembers his father standing on the front lawn of their home talking with Mr. Ochs, the neighbor across the street.

"Mr. Ochs actually worked at one of the plants out that way," Floyd said. "I think they were discussing which plant might be burning."

Floyd's father and uncle owned the Piggly Wiggly grocery store in Dumas. Floyd said his father usually spent Sunday morning before church at the store checking receipts from the previous Saturday. But that morning, he and Mr. Ochs decided to climb into Floyd's Chevy Bel Air and check out the distant fire.

"Of course, I hopped in the back seat," Floyd said. "I went everywhere my dadwent. Then Mr. Ochs' son George came running out. He was about 10 years old. He jumped in the back of the car."

Once they reached the open road, it quickly became apparent that the smoke was rising from the oil refinery. Floyd's father parked the Chevy on the main roadoutside the refinery fence, about 200 to 300 yards away from the fire.

"In this particular case we should have turned right around and gone back to town as soon as we saw it was a storage tank fire," he said.

For the next hour, firefighters would be occupied with burning liquid spilling from a possible line leak near the tank pump located inside a containment dike and a fire at the gauging device and vents, the NFPA article states. Eventually, flames from the dike fire rose 40-feet high, enveloping the spheroid.

No. 199 was one of two identical tanks built in 1940 and designed for a working pressure of 15 pounds per square inch, the article said. Each of these spheroids was equipped with two six-inch pressure-vacuum vents set at 15 psi connected toan eight-inch vent and tee connection. Both vents had return bend weather hoods that effectively acted as U-joints, directing anything escaping from the vents downward.

"In case of vapor ignition at the vents, as occurred in this case, there would result a direct flame impingement onto the top of the tank in the vapor space," the article said.

Tank gauging records show that there were 28 feet, seven inches of product inthe 46-foot-high spheroid, or approximately 12,000 barrels. A decision was made to begin pumping the contents out of No. 199. David White, an consultant with Fire& Safety Specialists, said pumping out the tank proved to be a tragic mistake. "Pumping out the tank is the worst thing you can do," White said. "It increases the flammable vapor space above the contents, making the tank more vulnerable to flame impingement."

Slowly, the potential for a catastrophic explosion increased.

"The plant fire brigade was severely limited in manpower since the fire occurredearly in the morning when the number of available men for firefighting was at the minimum," the NFPA Quarterly states. For this reason assistance from the volunteerfire departments of Dumas and Sunray was requested.

Bob Hamilton, a reporter for the Moore County News, entered the refinery againstadvice from the sheriff and plant guard. He reported that two groups of firefighters were attempting to approach the spheroid from opposite sides while a third group cooled nearby exposures. Three fire trucks were present.

"I was standing about 200 yards from the tank and took pictures but it was too hot to talk to people," Hamilton said. "It felt like my face was up against an open oven."

Smoke from the refinery drew spectators. The explosion came soon after.The NFPA Quarterly states the refinery brigade laid a hose line from a firehydrant in the process area to their foam truck.

"They attempted to use foam to extinguish the ground fire but experienced considerable difficulty due to the intense radiated heat," the magazine states. "It was reported that they were attempting to lay in longer foam lines prior to the rupture of the spheroid. The Sunray Fire Department laid in a water line on the downhill side of the tank farm and the Dumas Fire Department laid in a line from the upper side. All hose lines were approximately 900 feet in length."

Dumas and Sunray firefighters used the water available to them to keep adjacent tanks cool. Observers noted that hose streams were placed on a cone roof tank about 150 feet away from the burning spheroid. Another hose line was seen being used to protect a floating roof tank containing gasoline also about 150 feet awayfrom the fire. It was also reported that a water line was used at least once on No.199. Seal fires on adjacent floating roof tanks were promptly extinguished.

Hamilton wrote that a loud, roaring flame about 50 feet high spouted from a vent atop the burning spheroid. Flames from the ground fire were also intense. Firefighters were preparing to move closer with additional equipment when the alarm was sounded to evacuate. The rising heat had become too much, forcingfirefighters to even abandon cooling the other tanks.

From Floyd's vantage point, the layout of the tank farm made it difficult to seethe actual firefighting. Responders appeared to be occupied with a fire in the dikebeneath the spheriod storage tank and soon began throwing water on some of thesurrounding tanks. In the meantime, two or three other cars pulled up, bringingmore spectators.

"This one gentleman stopped and said 'You know, that looks like a pressurized pentane tank,'" Floyd said. "'If it is, we'd better be getting out of here.' No sooner had he said that you could hear this sort of whistling noise. It was venting from the top and there was a plume of flame that looked like it was shooting up from the ground to high above the tank."

The experts will tell you that the whistling Floyd describes is exactly the way an overpressure escaping through a relief valve sounds. That, together with the flames, made it a good time to start running, Floyd said.

"At 6:53 a.m., or slightly over an hour after the original fire was reported, the top of the spheroid ruptured violently," states NFPA Quarterly. That the spheroid lasted an hour surprised some, since LPG vessels exposed in a similar manner had ruptured in as little as 15 minutes.

BLEVE is a phenomenon often misunderstood, even by experienced firefighters.The textbook definition refers to a condition in which a chemical stored as liquid develops a gaseous vapor above it. Any rupture releases an overpressure of vapor inside. A sudden drop in pressure causes violent boiling of the liquid, refilling the vacant space with a terrific new overpressure of vapor. Such a significant overpressure destroys the vessel containing it.

At Sunray, as the tank metal heated by the flame jetting from the vent lost its tensile strength, a outward bulge probably developed. Even with the relief valve open, the building pressure inside would have eventually been sufficient to causea rupture or BLEVE.

"The flame impingement on the exterior tank surface from the burning vaporsissuing from the vent discharge points and possibly from the ground fire caused the metal shell of the spheroid to stretch and eventually fail due to the internal pressure in the tank," the NFPA Quarterly states. "The metal thinned out near theweld on the top (head-plate) over a distance of about one-third the circumference of the spheroid at this point."

Had flame impingement been below the vapor space, the liquid contents of thetank might have cooled the surface metal sufficiently to prevent failure.The top of No. 199 was sheared away by the force of the internal pressure release but landed within the tank dike.

"The remaining sections of the spheroid were also completely destroyed but likewise remained within the diked tank area," NFPA Quarterly states. "The entireventing assembly landed outside the dike." Investigators found the eight-foot-high gauging device about 700 feet away.

Hamilton's boss, news editor Bill Lask told the Associated Press he heard multiple explosions that were not sharp, but more like the big thud of a fireworks rocket.This was soon followed by an ear-numbing concussion of the BLEVE.

"I watched in disbelief as a bright orange mushroom of flame boiled up, floating in heavy black smoke, and I prayed that the firefighters would get out alive," Lask said.

Across the road, the fleeing spectators, Floyd included, jumped a barbed wirefence and ran across a freshly plowed field.

"I remember taking about three plowed rows in one step," he said. "Coming in behind us, there were refinery employees and firefighters running from the bulk station. I don't know how many seconds we ran before I looked back. I saw theperfect shape of an atomic bomb blast. A shadow passed over the ground in frontof me and I looked up again. I saw the mushroom cloud high above was overtakingus."

Then there was a blast of radiant heat that left everyone on the ground andstunned, Floyd said.

"Dad and I both had on short-sleeved shirts, and our arms were burned alongwith our ears," he said. "George didn't have a shirt on and he was burned worse.They rolled him in the dirt to try to keep him from burning more. That didn't help him much because it was hard to clean later."

Floyd's father got his son back to his feet and sent him running again. The nearest cover was a small metal structure about 200 yards away."Dad said 'Run to that shed and stay there until I come for you,'" Floyd said."' Don't come back no matter what happens. I am going to help Mr. Ochs with George and I will come and get you when it is safe.' He was afraid another tankwould go up."

At the refinery, people raced out of the billowing smoke in all directions, Lask wrote. Some were human torches. Others did not get the chance to run. They simply crumpled where they stood, their lives snuffed out by the initial blast. All ofthe immediate dead were found within 400 feet of the spheroid. Sixteen firefighters died at the scene with another three dying later from burns. Thirty-two others not so close, including many of the spectators on the highway nearly a quarter mile away, escaped with injuries.

Many of the dead and injured were personal friends, Lask said.

The fireball from the ruptured spheroid wreaked havoc throughout the tankfarm. It ignited a 20,000-barrel diesel oil tank 200 feet away that contained 6,500gallons at the time. Also ignited were two 10,000-barrel tanks of crude oil, onecontaining 6,000 to 8,000 barrels and, in the other, 2,000 barrels. These tanks were 450 and 550 feet from No. 199, respectively. All three tanks were cone roofed with flame arresters on the vents, NFPA Quarterly reports. Yet other tanks that werecloser did not ignite and suffered relatively little damage. The Oil and Gas Journalidentified these tanks as having floating roofs.

Industrial Fire World publisher David White said the coned roof tanks presented a danger in that they permitted vapor space above the product. By comparison, floating roof tanks allow no vapor space.

About 225 feet away from No. 199, two seal fires ignited on an 80,000 barrel floating roof tank. Responders subsequently extinguished both fires. A sixth tank smoldered but was also later extinguished. The heat blistered the paint on companyhouses 3,000 feet away. A workman protected in a shack 300 yards from the first explosion still suffered burns. Two bulldozers almost 1,200 feet away were destroyed by fire. The blast also ignited a railroad trestle 1,250 feet away and small piles of lumber along the railroad tracks in the refinery area. Leaves on trees a mile away showed damage.

Hamilton compared the heat to someone trying to burn your face off with a blowtorch. Flames were everywhere. He started running and did not stop to take another photograph until he reached the highway. For others, that wasn't far enough.

"Everyone around me was running into a plowed field to get farther away from that inferno," Hamilton said. "One was a boy about 11 (actually 13). He didn't have a shirt on and his back was burning. He was in terrific pain and was almost hysterical."

Another man's hair was smoldering, Hamilton said. Then the reporter realized his own hair was on fire. He later filed his story with the AP from the hospital. One source estimated that the contents of the spheroid dispersed to such adegree that it burned out within 10 minutes. Trying to reach the scene, Lask pushed to within an eighth of a mile before the heat forced him back. He met survivors stumbling in the opposite direction.

"Some were sobbing with the pain of burns," Lask reported. "I remember two men, moaning in smoldering shreds. They crawled into the bed of a pickup truckand were taken to a hospital."

While the written record is spotty, an excellent photographic record of the disaster exists. Judging from aerial photographs of the disaster, an area almost three-quarters of a mile had burned inside the refinery, Roberts said.

"A gentleman from Sunray who was a photo buff drove out that morning andsat on the highway taking pictures," he said. "His son gave me the originals. Among them is a sequence of three shots — one of the fire before the explosion,then a perfect picture of the explosion itself followed by a shot about 10 or 12 seconds after the blast. The fireball is the biggest I've ever seen in my life. "Neither Dumas nor tiny Sunray was geared for the aftermath of a disaster this size, the Dallas Morning News reported.

"But (Dumas) is a country town, and everybody helps everybody else," the newspaper said, "and by 11 a.m. — less than four hours after the disaster, all of the 32 burned had been taken care of in the previously quiet and calm 40-bed red brick Moore County Memorial Hospital."

A Moore County Sheriff's Office patrol car carried the Floyds and the Ochs tothe hospital. The injured were arriving by any means possible, including the rear ofpickup trucks.

He was assigned a bed but did not keep it very long.

"Later in the day, my dad came to me and said 'Junior, you need to grab your IV bag and come with me — they don't have enough room for the people who are dying,'" Floyd said. "'We're going home.'"

Both he and his father knew many of the 19 volunteer firefighters and refinery employees who died that day.

"It was a tough situation," Floyd said. "You've got to remember that there werepeople at this small hospital sitting with their backs to the wall who were dying. "About midnight the family doctor dropped by the hours to see that Floyd and his father were free of infection. For the rest of their lives, father and son would share the same set of distinctive scars from their experience.

"It almost looks like genetic birth marks," Floyd said.

Strangely enough, the family Chevy survived the withering heat without a scratch.

"If we had stayed in the car, we would have been okay."

Later that day, outside assistance began pouring into the area. National Guard personnel carriers and ambulances arrived on the scene. An airport crash truck responding from Amarillo Air Force Base was used to protect the floating rooftanks, extinguishing at least one seal fire. Emergency responders arrived from Amarillo and Dalhart. Little could be done except protect the remaining exposures.

"They controlled the ground fire as best they could, but basically they let thefire burn itself out," Roberts said. "That was about the only option at that point. "In the early evening, a high wind from the south blew flames from two large tanks still burning away from the tank farm. Amarillo Fire Chief Roy Hill, quoted inthe Dallas Morning News, noted that a wind shift to the north could create adangerous situation. Fortunately, the remaining tanks burned out the next day with no further incidents. The refinery was back in operation that same day.

Then came the funerals.

"I have a neighbor who was alive at the time," Roberts said. "She talks about how groups like the women's auxiliaries set up at the local churches and spent nearly two weeks doing nothing but getting the families to the funerals and cookingthem three meals a day."

In 2006, Floyd, a retired executive with Ryder Trucks, lived in Arlington, Texas.His father, 88, lives in Baytown, Texas. As for George Ochs, he survived his burns and is now a retired middle school principal in Hereford, Texas.

"It's amazing when a tragedy like that happens in a small town because peopleare able to start supporting each other immediately," Floyd said. "It doesn't do away with the private grief, but it helps the families of the fallen men from feeling so isolated."

The NFPA Quarterly article published several months after the fire cited theSunray disaster as "another case which condemns the widely accepted practice of locating tank vents on pressure tanks in such a manner as to permit flame impingement on a tank's vapor space." It also made note of the following:

• Installation of a fixed water spray system on all pressure storage tanks would have eliminated most of the hazard of a tank rupture by keeping the metal cool.
• If for any reason it is impossible to apply cooling water, all personnel should be removed at least 1,000 feet from the fire and, even at that distance, should wear protective clothing.
• Locating direct-fired heaters downhill from a volatile flammable liquid storage tank places an ignition source within the possible path of vapor travel.
• Cast iron should not be permitted in any flammable liquid piping, valves or connections.
• Pumps should be placed outside of a diked area to avoid exposure to fire.
• Adequate fire mains in tank farms need to be installed for firefighting operations. With the dead buried, life in Dumas and Sunray went on. With each passing year, the memory of the steep price paid at the refinery faded into history a bit more. Then, half a century later, somebody asked Mike Roberts what he was going to name his new fire station.

Today, the refinery has a throughput capacity almost 90 percent greater than in 1956. It produces conventional gasoline, RFG (reformulated gasoline), CBG (cleaner burning gasoline) and low-sulfur diesel. The refinery has access to crudeoil from northern Texas, Oklahoma, southwestern Kansas and eastern Coloradovia a 1,083-mile network of crude oil pipelines.

Expanding along with the refinery is the fire brigade. The new station is 175 feetby 150 feet with room for three drive-through fire truck bays. the refinery's brigade of 63 firefighters — all volunteers — operate with a fleet that includes a 5,000 gpm Pierce industrial foam pumper, a Mack 1,250 gpm pumper and a Mack 1,250 gpm foam tender.

When it came time to name the station, Roberts consulted some of his fellow fire chiefs as to any guidelines or protocol involved.

"One of them replied in a way that got my wheels turning," Roberts said. "I went to my plant manager and told him what I wanted to do and why. I didn't want to give the company a black eye, but history is history. I told him that I wasn't doing this for the company or for me, but for the survivors of the firefighters who died."

The manager, Bill Wuensche, supported the idea. He contacted corporate headquarters, which gave him and Roberts permission to run with it. Station 19 was born. But the idea didn't end there.

Entering Station 19, the first impression is that it is a museum. The entrance opens into a small area reserved as a memorial to the Sunray disaster. Nineteen plaques, each bearing the name of a fallen firefighter, adorn the wall. A glass case contains photographs of the fire and explosion, together with faded newspaper accounts. Also included is a group photo from the dedication ceremony in April 2006 showing 21 relatives of the 1956 fatalities.

Addressing the crowd, Wuensche gave a broad summary of the events thatoccurred 50 years earlier. History had been slipping away, he said, so the refinery believed it was only fitting that there be a permanent memorial at the refinery.The refinery presented the relatives with duplicates of the individual plaques honoring the firefighters. Atop each was the Maltese Cross, a firefighter's badge of honor. Roberts read aloud a history of the cross and then closed the ceremony with the Fireman's Prayer:

When I am called to duty, God

Wherever flames may rage

Give me the strength to save some life

Whatever be its age

Help me embrace a little child

Before it is too late

Or save an older person from

The horror of that fate

Enable me to be alert and

Hear the weakest shout

And quickly and efficiently

To put the fire out

I want to fill my calling and

Monument on the grounds of the Texas capital listing those killed at Sunray.

To give the best in me

To guard my every neighbor

And protect their property

And if according to your willI have to lose my life

Please bless with your protecting handMy children and my wife

"After that there wasn't a dry eye in the house," Roberts said.

The refinery then treated the visitors to dinner. Gifts honoring the relatives didnot end there. Each family received an eight-inch by 10-inch copy of the groupphotograph and an album with 50 other shots taken during the ceremonies. A copyof the album is included with the permanent memorial.

Working together, Gov. Rick Perry, State Rep. David Swinford and State Sen. KelSeliger added the crowning touch to the ceremonies. A resolution honoring the50th anniversary of the Sunray disaster and the dedication of the new fire stationwas introduced and passed by the Texas Legislature. Accompanying the resolutionwas a Texas flag flown over the state capitol building on April 19, and sent byairplane to the refinery for the ceremonies that same day.

The original plan was to place the flag directly into the glass enclosed memorialat the fire station. But one of the widows made a special request.

"She asked if I planned to ever fly the flag over the new station," Roberts said."I made a deal with her. On July 29, the official 50th anniversary of the disaster, Iran the flag up to full staff, then lowered it to half-staff for the rest of the day. Thenit went straight into the glass box on the wall.

Editor's note: This after-action review appeared in "Disasters Man-Made" by David White and Anton Riecher that was published in 2011.