Actions

2NEWS Investigates: Which safe rooms are safest -- above ground or below ground?

Posted
and last updated

TULSA -- Following the devastating May 2013 tornadoes we heard from many of you asking how to be certain a safe room will keep your family safe through a large tornado.

Tony Conner was there when the EF-5 tornado barreled into Moore.

"When you see a tornado that is that big you have no choice. It's either find cover or die," he said.

Ricky Stover also rode out the storm. He and his family didn't have a safe room so they took to their cellar.

"We locked the cellar door when we saw it coming and it got louder and the next thing you know you see the latch coming undone and you couldn't reach for it and it ripped open the door. Glass and debris started slamming on us," Ricky said.

PHOTOS - Images of the Moore tornado destruction

The Stovers all survived but many of you turned to the 2NEWS Problem Solvers and our meteorologists in the wake of the deadly storms asking which type of safe room is best.

Amidst the debris in the path of the EF-5 tornado that tore through Moore we found safe rooms that survived; both above and below ground.

But we wanted to know whether above or below ground is safest because just as the Moore tornado began to hit, people were being told the only safe place to be is underground.

FEMA says in the right safe room your family will have near absolute protection even in storms whipping up to 250 miles per hour.

Greg Stephens and his family took to their safe room as the deadly Moore tornado descended on them.

"Usually the ones that come around here they kind of come close but never had a direct hit," said Greg.

This time it was a direct hit.    

The storm sucked the door open on the family's underground safe room.

"It was scary in respect that I thought I might lose someone in my family."

It's a worst case scenario: 250 mph wind with flying debris.

Could above ground safe rooms hold as well? 

To find out we traveled to the Texas Tech Wind Research Center. At the facility in Lubbock, Texas scientists use a wind cannon to launch wood and metal to simulate wind and damaging storm debris. It can produce EF-5 level tornado damage.

The cannon simulates wind of 250 mph. The researchers line up a safe room to take the hits with objects including 2x4's fired at the shelter's most vulnerable spots such as away from studs and into the door.  A storm shelter would be considered a failure if the steel is pushed inward more than three inches. 

Wayne Bullington, with the help of his 5-year-old son Cayden, built a safe room using his own money and brought it to the wind research center for testing. He paid $4,000 to have his above ground safe room put to the ultimate test.

"A lot of individuals couldn't go underground. They had shelters, but they weren't able to get into those shelters," said Wayne.

Tensions are high as Wayne waits to see if his safe room passes. "I spent a great deal of time trying to redesign the shelter to be an above ground shelter that was accessible and safe."

The cannon fires a series of EF-5 level shots. The safe room performs perfectly.

Barely more than one inch of impact, no holes and the door remains sealed. The shelter would also remain attached to the ground during a tornado. Huge, specially-made bolts driven into at least 4 inches of concrete prevent this one-ton shelter from being picked up or pushed over.

So now, back to our question -- which is superior?  Above or below ground?

Larry Tanner, research associate at the Wind Research Center, says most importantly your safe room must be designed and built to FEMA guidelines. 

"They're all safe if they are tested products," said Tanner.

However, in a below ground safe room you face the risk of debris blocking the exit, or flooding.

The good news: No one has ever been killed in an approved safe room whether above or below ground.

And after seeing video footage of cars picked up and tossed by tornadoes many of you asked whether above ground safe rooms will stand up to cars falling out of the sky? 

Tanner says safe rooms built to FEMA guidelines handle a 3,000 pound vehicle being dropped on them no problem.

"The 57 Cadillac draping over the sides of the shelter. That's virtually what we see all the time," Tanner said.

Click here for FEMA information on residential safe rooms. You can also call the safe room help line, 1-866-927-2104

Here is information from the Federal Alliance for Safe Homes (FLASH).   During a conference of leading experts in tornado science, meteorology and construction participants set the record straight on tornado safety and building practices dispelling myths and clarifying misinformation that emerged following the outbreak of tornadoes in Oklahoma and Texas:

Myth #1:  Attempting to drive away from a tornado is a better survival plan than sheltering in place.

Fact: Tornadoes do not follow a specific path or route and can change direction at any time, so attempting to drive away is an extremely risky choice.  Tornadoes can turn a car into a 4,000-pound flying missile and occupants can become trapped and exposed to debris, rain, hail and/or dust.  Parking on traffic lanes is dangerous and illegal, and stalled or stopped cars can block emergency vehicles. 

"A car is a more dangerous place to be than a well-constructed home in a tornado," said Greg Carbin, Meteorologist for the National Weather Service's Storm Prediction Center.

The best place to shelter in a tornado is indoors.  However, if you are already in your car and a tornado is approaching, know that there is no safe option, just slightly less-dangerous ones.  If the tornado is visible, far away, and the traffic is light, you may be able to drive out of its path by moving at right angles to the tornado.  If you are caught by extreme winds or flying debris, park the car as quickly and safely as possible -- out of the traffic lanes.  Stay in the car with the seat belt on.  Put your head down below the windows; cover your head with your hands and a blanket, coat or other cushion if possible.  If you can safely get noticeably lower than the level of the roadway, leave your car and lie in that area, covering your head with your hands.  Avoid seeking shelter under bridges, which can create deadly traffic hazards while offering little protection against flying debris.

Bottom Line:  Develop a personal plan for safety well ahead of tornadoes and identify your safe place options at home, school and work.  Start with certified shelters and safe rooms, safe spaces above or below ground, or community shelters in public spaces that are labeled as official tornado shelters like stores, malls, churches or even airports. 

Myth #2:  Not everyone can receive tornado watches and warnings.

Fact:  Using a combination of NOAA weather radio and new smartphone weather alerting apps all but assures that you will receive lifesaving severe weather alert information and other emergency messages on a timely basis.  NOAA Weather Radio has delivered reliable watches and warning for more than 50 years and the advent of new, smartphone GPS, precision weather notifications have added enhanced mobility, speed and accuracy for families in harm's way.

Bottom Line:  A Tornado Warning is issued when a tornado is imminent and the average lead time for tornado warnings is 13 minutes, so swift and accurate alerting is necessary. "Approximately 97 percent of Americans are within range of a NOAA weather radio broadcast," said Walt Zaleski, Warning and Coordination Meteorologist, Southern Region, National Weather Service.

Myth #3:  Nothing above ground can withstand an EF-4 or EF-5 tornado.

Fact:  It is entirely possible to harden and stiffen a room to withstand extreme winds, i.e. a small room, steel or concrete, or timber box equipped with a door that has been tested for pressure resistance and debris impact resistance.  The National Storm Shelter Association/ICC 500 standard and FEMA guidelines provide details on how to fabricate shelters or construct safe rooms that provide near absolute life protection, even in an EF-4 or EF-5.   

Bottom line:  Expert forensic engineering examination of above-ground shelter and safe room performance during the 2011 Tuscaloosa and Joplin outbreaks as well as the May 20, 2013 Moore, Oklahoma tornadoes documented that properly constructed shelters and safe rooms consistently survive super tornadoes.  "In my 15 years of doing storm damage research and storm shelter research, we have never documented any deaths or injuries in above ground tested safe-rooms or failures of tested safe-rooms.  This includes the storms of Joplin 2011 and Moore 2013," Larry Tanner, Texas Tech University Department of Construction Engineering and Engineering Technology.

Myth #4:  Building codes cannot make a difference in tornado outbreaks.

Fact:  Even if the tornado is EF-4 or EF-5, 95 percent of the damage occurs at EF-3 and below.  What this means is that the minimal construction standards required by building codes can make a meaningful difference if they are adopted and enforced.  Moreover, since 90 percent of all tornadoes never exceed EF-2, wind resistant building practices like those included in the 2012 International Residential Code can dramatically improve building performance in tornado outbreaks.

Bottom Line: Homes built to modern, model codes will have the advantage of better wall bracing, improved roof tie-downs and overall stronger connections.  "If we can put a man on the moon, we can keep a roof on a house," said Dr. David Prevatt, Assistant Professor University of Florida Wind Department of Civil and Coastal Engineering.

Myth #5:   We cannot affordably build to withstand tornadoes.

Fact:  The National Climatic Data Center estimates that 77 percent of U.S. tornadoes are in the EF-0 to EF-1 range and 95 percent have wind speeds less than EF-3 intensity.   A recent cost study revealed that using an average of $0.50 per square foot or $1,000 in metal connectors installed from a home's roof to its foundation could upgrade a home's ability to withstand wind uplift from an EF-0 to an EF-2 tornado.  

Bottom Line:  Approximately 90 percent of tornadoes are at the EF-2 level or lower. "An increase in baseline construction costs of just $.50 per square foot can boost a structure's wind resistance from EF-0 to EF-2 levels," said Randy Shackelford Research Engineer/Code Specialist Simpson Strong-Tie.  A minimal investment of $.50 per square foot or $1,000 for a 2,000 square foot home will help save lives and minimize property damage.

Panelists for the event included:
 

·        Greg CarbinWarning Coordination Meteorologist, National Weather Service/NCEP Storm Prediction Center

·        Leslie Chapman-HendersonPresident and CEO, Federal Alliance for Safe Homes (FLASH)

·        Dr. David PrevattAssistant Professor, University of Florida Wind Department of Civil and Coastal Engineering

·        Randy ShackelfordResearch Engineer/Code Specialist, Simpson Strong-Tie

·        Larry TannerTexas Tech University Department of Construction Engineering and Engineering Technology

·        Walt ZaleskiWarning and Coordination Meteorologist, Southern Region, National Weather Service

To download the event presentation, visit www.flash.org.

About FLASH
Federal Alliance for Safe Homes (FLASH)®, a 501(c)3 nonprofit organization, is the country's leading consumer advocate for strengthening homes and safeguarding families from natural and manmade disasters. FLASH collaborates with more than 100 innovative and diverse partners that share its vision of making America a moredisasterresistant nation including: BASF, Federal Emergency Management Agency, Florida Division of Emergency Management, The Home Depot®, International Code Council, Kohler® Generators, National Weather Service, Portland Cement Association, RenaissanceRe, Simpson Strong-Tie®, State Farm™, USAA® and WeatherPredict Consulting Inc. In 2008, FLASH opened the interactive weather experience StormStruck: A Tale of Two Homes® in Lake Buena Vista, FL. Learn more about FLASH and gain access to its free consumer resources by visiting www.flash.org or calling (877) 221- SAFE (7233). Also, get timely safety tips to ensure that you and your family are protected from natural and manmade disasters by subscribing to the FLASH blog – Protect Your Home in a FLASH.