Insurance Institute for Business & Home Safety • 2013 • Volume 1

Disaster Safety Review

Successful Hail Field Study Produces Valuable Data 2

IBHS Urges Congress to Fund Critical Wind Research 5

Tornadoes: Narrowing the Path of Damage 6

Table of Contents

SUCCESSFUL IBHS HAIL FIELD STUDY YIELDS VALUABLE DATAUnderstanding hail and hailstorms requires more than just developing theories about these phenomena. At some point, researchers have to go where these natural events occur to gather the evidence needed to test those hypotheses.

A pair of research teams from the Insurance Institute for Business & Home Safety did just that this spring. Carefully tracking tornadoes and violent, severe thunderstorms for many days, the teams completed a unique and highly successful hail field study as a part of the Institute’s multi-faceted hail research effort.

Dr. Tanya Brown, IBHS research engineer and occupant of the South Carolina Wind and Hail Underwriting Association Junior Chair in Research, and Dr. Ian Giammanco, IBHS research scientist, led two separate deployments to the Central Plains region of the U.S. in May and June, driving thousands of miles to measure the mass, dimensions, and compressive strength of hundreds of hailstones produced by supercell thunderstorms.

These valuable data on hailstone characteristics will be used in research projects at the IBHS Research Center, so that scientists can gain a clearer understanding of how hail damages various building materials, as well as how to significantly improve risk modeling and weather forecasts.

“We will be doing meticulous lab work to try and recreate what we found in the field,” says Giammanco. “Our current lab methods are variable in terms of hailstone hardness and it will take a lot of time to begin consistently

recreating hail with the specific characteristics we have observed in the field.”

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CHECK OUT THE VIDEO HIGHLIGHTS AT DISASTERSAFETY.ORG(or click below if you are viewing online)

DATA COLLECTIONIBHS completed its first hail field study in 2012. The findings from that research led to creation of the first-ever, full-scale indoor hailstorm in February 2013 at the IBHS Research Center. This year, the re-search team collected nearly three times as many hailstones as it did in 2012, in-cluding the largest hailstone recorded in the two-year project history, which mea-sured 4.21 inches in diameter.While finding large hailstones was impor-tant, it is the amount of data collected on smaller hailstones that could help uncov-er the answers to many unknowns.“Bigger hailstones have a bigger mass, and will cause damage at impact be-cause of that higher mass,” Brown says. “However, it’s when we get into the inch and inch-and-a-half diameter hail that we don’t know how the combination of hard-ness, size, and mass affect the amount of damage – and most storms produce hailstones that size, rather than the huge stones. The more we know about this kind of hail, the more accurately we can understand how buildings are damaged, and what can be done to prevent or re-duce that damage.”IBHS research teams also observed and cataloged the types of hailstones com-monly referred to as “slushy,” which will provide valuable data for recreating sim-ilar hailstones. This could help answer long-standing questions about the par-ticular impact of this type of hailstone.“A slushy hailstone probably wouldn’t cause significant damage, but what kind of impact does this kind of hail have on an aged roof? We just don’t know yet,” says Giammanco. “Data on this type of hailstone are just as valuable as the hard hail data. Knowing the type of hailstones that are typically associated with a certain kind of storm and its environment will al-low insurers to more accurately address claims.”In May, three staff members from State Farm joined IBHS researchers in the field, which made it possible to deploy two teams instead of one. “Having the extra

manpower enabled us to collect and mea-sure twice as many hailstones, and facili-tated getting the broad spatial coverage that we did,” said Brown.State Farm™ has a long history of hail re-search, said Rose Grant, State Farm pro-gram director. She called the IBHS re-search “critically important” and “really impressive,” adding that “the information gathered by the IBHS-led teams is data that no one has previously collected; it is providing new facts and details for us to consider.”

DUAL-POLARIZATION RADAR

The large collection of data during this field study will help create a more accu-rate picture of how hailstones vary by storm. These data will have significant and immediate impacts on the effectiveness of the National Weather Service’s (NWS) network of dual-polarization Doppler ra-dars, says Brown.Although dual-polarization can greatly improve estimates of hail size and loca-tion, the mathematical formulas used to extract this information are still not per-fect. Using data collected during IBHS’ field studies, the improved dual-polar-ization radar algorithms can narrow the range of uncertainty, which will greatly improve the weather forecast enterprise and event classification, and risk analyses conducted by the insurance industry.“The dual-pol radar can detect hail and what size it is, but that is something that you have to train the analysis computer to do,” Brown says. “The data we provide will help tune the radar algorithms for what is happening on the ground. Currently, the radar sees a value but it has little idea of what it means. You have to feed it the ground-truth data for it to provide an ac-curate representation of what is happen-ing, which is what the data we collected in the field will help do.”

SAFETY FIRSTKeeping the field teams safe during de-ployment is IBHS’ highest priority. This

year, IBHS research teams were confront-ed with dangerous weather on several oc-casions. On May 20, the day that an EF-5 tornado struck the Moore, Oklahoma area, the IBHS teams were approximate-ly 40 miles south of Moore. Just 11 days later, disaster struck again while the re-search teams were back in the field. This time, a massive EF-5 tornado struck El Reno, Oklahoma, killing 20 people, in-cluding three storm researchers from an-other organization. Despite the close calls with disaster, team members were posi-tioned well out of harm’s way as a result of constant weather radar monitoring by Giammanco.“We use radar coverage regularly and also use our eyes,” said Giammanco. “We typically position the teams south of the storm and wait for the core to move through before we proceed into the hail swath. You generally know the direction of the storm and stay out of its path. We’re never going to put the team in a vulner-able position. For this type of work, you just don’t need to do that. Equally as im-portant as vigilant weather monitoring is ensuring we have an escape route in the event the target storm behaves a bit more unexpectedly. We also avoid un-paved roads at all cost.”

SEVERE WEATHER AND ITS CONSEQUENCES

While the IBHS research teams safely and successfully completed the objectives of the last two deployments, the violent weather the teams encountered is a re-minder of how dangerous it can be in the field. Because of the deadly torna-does, the 2013 IBHS hail field study will be viewed a little bit differently.“It was a very successful year in the field, but it was also a tough year because the weather was so active and severe,” says Brown. “The fatalities of fellow research-ers in the field was very difficult from a personal perspective. We do this research, and we love what we do, but it does affect us as well.” continued on page 4

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continued from page 3

WHAT IS

Dual-Polarization Radar?

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We will be doing meticulous lab work to try and recreate what we found out here

“

“

DR. IAN GIAMMANCO

Dual-polarization radar sends and receives both horizontal and vertical pulses of energy, providing a much more informative two-dimensional picture of severe weather. Conventional Doppler radars only send out a horizontal pulse of energy that gives forecasters a one-dimensional picture of severe weather.

By providing more information about the type of precipitation in the atmosphere and its intensity, size, and location, dual-polarization radars increase the accuracy of forecasts and allow for more accurate and timely severe weather warnings. In addition, dual-polarization more clearly detects airborne tornado debris, which allows forecasters to confirm if a tornado is on the ground and causing damage.

The first operational radar upgraded to dual-polarization was at Vance Air Force Base near Enid, Okla., on March 8, 2011. All dual-polarization upgrades have been completed at every NWS-operated Doppler radar in the U.S.

(SOURCE: NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION)

NEXT STEPSBrown, Giammanco and other IBHS re-searchers will continue their work to better understand hailstones, which will help re-duce the property damage caused by hail. In addition to recreating hailstones and pro-viding valuable data for dual-polarization ra-dar, IBHS will conduct small panel tests, and work on developing platforms that could re-cord hailstone information as they fall dur-ing a passing storm.

“Overall, we are going down the correct road,” Giammanco says. “We are getting there, but it will take time to get everything correct.”

The Insurance Institute for Business & Home Safety (IBHS) is the insurance industry’s only organization dedicated entirely to property loss mitigation. As a 501(c)(3) non-profit group, the Institute does not lobby; however, IBHS provides extensive technical counsel and expertise on building science research and property mitigation issues in the public policy arena. This work advances IBHS’ ultimate goal of helping to create safer, stronger communities.

A good example of this technical work is IBHS’ support of a robust national advocacy coalition known as BuildStrong, which has been built around IBHS research; the coalition is advancing federal legislation (H.R. 1878/S. 924) providing incentives for states that enact and enforce a modern statewide building code.

IBHS’ work in this area also was on display during a recent congressional hearing about the need for more wind mitigation research in the U.S. IBHS General Counsel and Senior Vice President of Public Policy Debra Ballen testified in support of the National Windstorm Impact Reduction Program (NWIRP), H.R. 1786, during a June 5 joint hearing of the U.S. House Science, Space, and Technology Subcommittees on Research and Technology. IBHS and its members long have strongly supported

windstorm research and development of cost-effective mitigation measures to reduce wind-related losses; this hearing provided a high-profile opportunity to support NWIRP, and the need for coordinated, federally funded windstorm research.

In her testimony, Ballen noted that IBHS “recognizes that our research and guidance must be corroborated and expanded on by others in order to gain broader acceptance in the marketplace.” Ballen also proposed areas of research where NWIRP should focus its efforts, all of which closely mirror IBHS’ activities: better understanding of windstorm events and their effect on the built environment; improved building codes and mitigation tools to more effectively assess design and mitigation improvements; and, a review of current test methods, standards and tools to ensure that high-wind rated products perform as expected in actual events.

IBHS leveraged another occasion to advance stronger mitigation efforts at the national, state and community-level when it submitted comments June 21 to the Federal Insurance Office (FIO) in response to its call for comments as part of its “Study on National Catastrophes and Insurance” – which is part of the FIO’s upcoming Biggert-Waters Flood Insurance Reform Act Report to Congress.

In these comments, IBHS asserted that effective mitigation can be affordable and cost-effective to property owners. Several examples of research conducted by IBHS were provided, each demonstrating that relatively inexpensive improvements to a building, such as sealing the roof deck and creating a continuous load path, can greatly reduce weather-related damage.

IBHS also highlighted the importance of strong, well-enforced building codes in reducing property losses, and noted the cycle of vulnerability and destruction that is created when post-disaster construction of homes, businesses and public buildings occurs in areas where there are known natural hazards, or a pattern of historical losses. In addition, IBHS’ first-of-its-kind “Rating the States” building code report was cited, highlighting specific recommendations for coastal states that would improve their building code regimes.

Other IBHS priorities noted in the comments included the importance of validating the bases of future mitigation incentive programs, along the lines of the third-party quality control currently required by IBHS’ Fortified HomeTM program. This type of third-party validation ensures that any structural improvements are correctly completed to provide a real reduction of risk.

IBHS will continue to serve as a technical resource on building science research and property

mitigation issues in the public policy arena to advance the goal of strengthening homes, businesses and communities against natural disasters and

other causes of loss.

IBHS Helps Advance Federal Windstorm Research Funding and Property Mitigation Efforts

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CLICK TO VIEW THE TESTIMONY

This was the scene on May 20, 2013, after an EF-5 tornado ripped through Moore, Oklahoma, killing 24 people. Just 11 days later, another devastating EF-5 tor-nado struck south of Moore in El Reno, Oklahoma, leaving 20 people dead. The images of destruction reflect how violent these storms were and can be. But they also beg the question – what can be done to reduce the amount of damage torna-does cause?Although a structure is likely to suffer sub-stantial damage or be totally destroyed by an EF-5, EF-4, or even EF-3 tornado, there are ways to reduce damage caused by both lower severity tornadoes and around the periphery of powerful torna-does like those that devastated Moore and El Reno.“We can narrow the path of tornado dam-age,” says Julie Rochman, IBHS president and CEO. “We could effectively eliminate EF-0 and EF-1 damage if we made homes less brittle, tied them together properly and protected all the openings.”However, before property owners can be-gin to think about stronger, safer building choices, it is vital to address life safety is-sues. While building a storm shelter is one solution, residents without one should have an action plan for when tornadoes threaten.

LIFE SAFETY AND BUILDING SAFETY

“You need to put as many walls as possi-ble between you and the outside storm,” advises Dr. Tim Reinhold, IBHS chief en-gineer and senior vice president for re-search. “If there is a tornado watch – and

definitely when warnings are issued – seek a substantial structure, low to the ground and without windows or other openings. Unfortunately, since severe weather can form quickly, there is of-ten not a lot of time to move to the ideal location.”Dr. Ian Giammanco, IBHS research sci-entist, says that building a storm shelter should be the first priority for homeown-ers that face a high tornado risk. But if that isn’t feasible, there are ways to reduce sig-nificant damage to a home. The best ap-proach is to take steps to reduce the risk to both people and buildings, he said. “Life safety and building safety are inter-twined,” Giammanco says. “Coupled with a storm shelter, there are ways you can have a structural system that is effective for life and building safety.”

CREATE A CONTINUOUS LOAD PATH

Reinhold says the first step to reducing a building’s risk during high winds cre-ated by a tornado is to create a continu-ous load path throughout the home. This includes installing reinforcement straps that attach the roof to the walls, as well as installing anchor bolts that connect the walls to the foundation. Without these connections that travel from the roof to the foundation, your house is vulnerable to wind forces. Find out how vulnerable a house can be without the right connec-tions in this video of windstorm testing at the IBHS Research Center.“Creating a continuous load path will help reduce losses and increase the chances that you can go back to your home after a storm has passed,” Reinhold said.Going home could be months or even years away for the thousands of displaced residents in Moore and El Reno. Sadly, this was the experience of many Joplin,

Missouri, citizens after a massive EF-5 tor-nado struck the town in May 2011. That storm killed 161 people, left hundreds in-jured, and left thousands homeless. The Federal Emergency Management Agency (FEMA) recently announced that the last of nearly 600 mobile trailers used to house displaced residents in Joplin finally will be removed, more than two years af-ter the disaster.

STRENGTHEN OPENINGS

In addition to creating a continuous load path, strengthening a structure’s open-ings – particularly garage doors – can increase the chances of a home’s sur-vival in a severe wind storm. Dr. Tanya Brown, IBHS research engineer (and occu-pant of the South Carolina Wind and Hail Underwriting Association Junior Chair in Research), participated in the National Weather Service’s official survey of the Moore tornado damage one day after the storm. During the damage survey, Brown noted the problems associated with ga-rage door failures.“A lot of the failure points for many of the homes began at the garage door,” says Brown. “Many openings caused by a ga-rage door failure pressurized the inside of homes and pushed up on the roof sheath-ing, which caused significant damage to the garage as well as also other areas of homes. It seems to be a common problem and it shows that damage is a very pro-gressive thing. Once started, it is hard to stop its progression.”

STRENGTHEN CODES AND STANDARDS

While building codes close to the Gulf or Atlantic Coasts often have provisions re-lating to protection against high winds, that is not the case inland, where convec-tive storms, including tornadoes, often

STREETS LINED WITH DEBRIS, CARS OVERTURNED, TREES UPROOTED, AND A CITY LEFT IN RUINS.

TORNADOES:

Narrowing the Path of Damage

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wreak havoc. As Rem Brown, IBHS senior engineering manager, notes, “homes lo-cated in areas with high tornado risks generally are not constructed to with-stand severe high winds, because de-sign wind speeds which form the base of building codes and standards are usually less than 110 mph.”Fortunately, wind loss mitigation steps do not require the force of law to be imple-mented. Home and business owners can take steps any time to harden their new or existing structures, using IBHS or federal guidance (which aligns closely with IBHS). Brown says that improving building con-struction should be a priority in the cen-tral U.S.One way property owners can improve building construction is by following IBHS’ FORTIFIED HomeTM standards for the high winds and hail that are often as-sociated with tornadoes. The FORTIFIED program features practical, meaning-ful solutions for new, as well as existing homes, including creating a continuous load path and reinforcing garage doors to withstand high wind speeds.It is important to note that FORTIFIED standards are not designed to prevent damage from EF-3, EF-4 and EF-5 torna-does which pack the highest wind speeds, but they can reduce property damage caused by lower level tornadoes and near the edges of severe tornadoes.

EF-5 TORNADOES ARE VERY RARE

“At a certain point, physics will overwhelm even the best engineering,” Rochman said. “Fortunately, the vast majority of tor-nadoes in the U.S. every year are lower level EF-0, EF-1 and EF-2 storms, for which there are numerous things we can do to reduce damage.”According to the National Climatic Data Center (NCDC), 77 percent of tornadoes have wind speeds less than 110 mph, and more powerful tornadoes, such as those that devastated Moore and El Reno, ac-count for only one to two percent of tor-nadoes affecting the U.S. each year.

In addition, Dr. Tanya Brown notes that dam-age documented after the Moore tornado re-vealed that only one single point of the tor-nado’s path showed EF-5 damage. “Even in violent tornadoes, there is not a mile wide swath of EF-5 damage,” says Brown. “During the biggest event, the damage is confined to a narrow path. If you are on the edges of a tornado’s path, en-hanced construction will definitely help you.”A recent report on the 2011 Joplin tornado by the American Society of Civil Engineers shows that more than 83 percent of damage during the pow-erful EF-5 tornado was caused by wind speeds of 135 mph or less, the equivalent of an EF-2 tornado. In addition, only four percent of damage from the storm could be linked to an EF-4 tornado, while inves-tigators found no EF-5 level damage at all. The study concluded that because poor-ly built structures were not able to with-stand high winds, flying debris from de-stroyed buildings increased the amount of property damage caused by the tor-nado. The study suggests that had homes been built with a continuous load path, some of the damage could have been avoided.

NEW REQUIREMENTS IN JOPLIN

The Joplin City Council has approved a re-quirement that all new construction must include hurricane clips on every rafter and truss. In addition, the council also ap-proved a requirement that the spacing of anchor bolts attaching a building’s wood frame to the foundation must be four feet apart, rather than six feet apart. Whether

Oklahoma will follow Joplin’s lead and improve building standards to reduce damage from storms remains to be seen.“It would be very beneficial to have a strong statewide building code in states that are prone to tornadoes. The goal is to reduce the amount of damage that occurs as much as possible, and stronger mini-mum standards would help,” Rochman stated. In the meantime, she notes, IBHS will continue advocating for stronger, safer building construction practices to reduce high wind property damage by “forcefully pushing science-based guid-ance in areas with high wind risks.”“We know from a building science per-spective how to narrow the path of dam-age that occurs during a tornado,” says Rochman. “We just need the will to make that happen.”

Narrowing the Path of DamageHOW IS

A Tornado Rated?

EF-0

EF-1

EF-2

EF-3

EF-4

EF-5

65-85 mph

86-110 mph

111-135 mph

136-165 mph

166-200 mph

>200 mph

EF Rating Wind Speeds3-Second Gust (mph)

The Enhanced Fujita (EF) Scale is a set of wind estimates (not measurements) based on damage. The EF Scale is used to assign a tornado a ‘rating’ based on estimated wind speeds and related damage. Tornado-related damage is surveyed after the storm and is compared to a list of Damage Indicators (DIs) and Degrees of Damage (DoD) which help estimate the range of wind speeds the tornado likely produced and it is from this information that a tornado is given an EF rating.(Source: National Weather Service)

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WHAT TO DO DURING A TORNADO

WHAT TO DO DURING A HAILSTORM

• Tune in to your radio to stay informed of approaching storms.

• Immediately go to the closest sturdy shelter. However, never try to outrun a tornado. Instead, leave your vehicle immediately for safe shelter.

• If your vehicle is hit by flying debris while you are driving, pull over and park. Stay in the vehicle with your seat belt fastened. 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.

• Do not stay under an overpass or bridge. You are safer in a low, flat location.

• Avoid downed power lines.

• Approach intersections with caution. Treat traffic lights at intersections as stop signs both during and after a storm.

• Go to a pre-designated shelter area such as a safe room, basement, storm cellar, or the lowest level in the building.

• If there is no basement, go to the center of an interior room (closet, interior hallway) on the lowest level away from corners, windows, doors, and outside walls.

• Put as many walls as possible between you and the outside. Get under a sturdy table and use your arms to protect your head and neck.

• In a highrise building, go to a small interior room or hallway on the lowest floor possible.

• Do not open windows.

• Tune in to your radio to stay informed of approaching storms.

• Do not drive unless absolutely necessary.

• If you see a tornado or hear a tornado warning, don’t try to outrun it.

• Pull safely onto the shoulder of the road away from any trees that could fall on the vehicle.

• If at all possible, pull into a sturdy garage, parking garage, or under a shelter to minimize hail damage.

• Stay in the vehicle and turn on the emergency flashers until the heavy rains subside.

• Avoid downed power lines.

• Approach intersections with caution. Treat traffic lights at intersections as stop signs both during and after a storm.

• After the storm, thoroughly evaluate your vehicle for damage.

• If you find glass damage, carefully remove any glass from the interior of your vehicle, and cover the damaged area to prevent further water damage to the interior.

IF YOU ARE OUTSIDE: (NO SHELTER) IF YOU ARE INSIDE: