Tropical cyclone preparedness

"be... hurricane prepared" (HHS).

Hurricane preparedness includes actions taken before a tropical cyclone strikes to mitigate the damage and personal danger such storms can cause. Personal preparedness consists of actions that individuals can take, anywhere from hours to months before a storm may strike, that minimizes the damage a cyclone can do to their possessions and improves their chances of coming through the storm safely. Hurricane mitigation uses policy adherence and enforcement to make buildings and other property more resistant to the effects of tropical cyclones.

Hurricane mitigation

Evacuation route sign on Tulane Avenue in New Orleans shows lines from long standing floodwaters after Hurricane Katrina

Hurricane or Tropical cyclone Mitigation concerns measures taken and products designed to lower the likelihood of damage from hurricanes and tropical storms. All buildings, whether residential or commercial, are vulnerable to damage from storms. In addition to the facilities themselves being at risk, the internal contents of the structures can be damaged as result of exposure to water if the building envelope is breached, usually as a result of the strong winds associated with hurricanes and tropical storms. Although the negative pressure caused by high velocity wind flowing over a building roof can cause the roof to fail with the building envelope intact, broken windows allow the air pressure to rise inside a building, creating an even greater pressure difference, and increasing the likelihood of roof failure. This pressure increase results after an opening, that is, a window or door, is breached after being struck and broken by wind blown debris.

For people who live in a hurricane-prone area, the major decision that must be made when a hurricane approaches is whether to stay or go. Regardless of that decision, however, it is in their best interest to have the home prepared to the maximum extent possible, well in advance of the annual hurricane season.

The whole idea behind these mitigation measures and products is to increase the likelihood of having a home to come back to after the storm. There is no iron-clad guarantee that these measures will safeguard any home against any kind of storm and the projectiles that may come with a storm, but a well-protected home is far more likely to come through a hurricane in better shape than a home that has little or no protection.

There are many options open to the homeowner looking to protect their property. They range from simple and affordable steps that can be taken to strengthen and fortify a residential home's resistance to a hurricane's impending high winds, to more elaborate and expensive systems.

The most important decision is to locate the building outside of range from the coast that is exposed to storm surge. Regardless of protection from the effects of wind, a building can be flooded or destroyed by storm surge.

To mitigate the effects of high winds and associated debris impact, a good first step is to have the home checked out by an experienced hurricane mitigation professional. Many hurricane protection companies offer free consultations as part of their marketing strategy. The State of Florida has taken steps to help its homeowners in the area of hurricane preparedness through its My Safe Florida Home grant program. Qualified homeowners receive a free in-home assessment of their home's hurricane readiness. A report is issued identifying vulnerable areas of the home and recommending various options for upgrading the home's safety. The homeowner can then contract with a hurricane protection company for the improvements, and the state matches funds spent by the homeowner, up to a $5,000 limit.

When making these types of home improvements, there are two major areas of focus: the roof and the openings. Over the roof hurricane harness straps protect the structure's roof from lifting off and can be installed well in advance of the impending storm. There are other methods of strengthening a structure's roof, such as strengthening the building internal structure and adding nails to the roof.

Protecting the openings in the home is very important. Window and door coverage provides protection from both high winds and airborne projectiles. Both of these conditions are capable of causing a breach to the building's envelope, putting the roof at risk of blowing off. The garage door should be protected, either by bracing it or by installing other protection, such as hurricane fabric screens. These screens, made of a strong woven fabric, are capable of covering and protecting garage doors, as well as windows, doors, and lanais.

History

Evacuation during Hurricane Rita in 2005.

Recent windstorm activity, in the United States in particular, has focused interest in measures that can be used to lower the likelihood of damage to structures. Billions of dollars of damages have resulted from such strong winds and the manner in which structures have been built in the affected areas in the United States.

Building codes are beginning to address mitigation measures, particularly in the State of Florida. The work that has led to the changes in the Florida Building Code [7] was influenced by scientific observations and lessons learned by an Institute of the Florida International University [8] called International Hurricane Research Center [9].

Product certification

Few codes make the use of hurricane mitigation products mandatory. As the field is rather new to construction, few standards exist to address uniform testing or product certification of product installations.

One regional effort is in Miami-Dade County in the State of Florida in the USA. The county's Building Code Compliance Office, certifies hurricane mitigation building products, such as window shutters. The construction methods incorporated into the Florida Building Code are reported to have stood up fairly well to Hurricane Katrina. The majority of houses now have not been built to the new code. Miami-Dade County's jurisdiction does not exceed its boundaries and no building code or fire code forces homeowners to retrofit existing buildings with any hurricane mitigation measures.

Test facilities

There is no single test standard or facility capable of qualifying the protection of an entire building. The Cyclone Testing Station in Australia can test building systems (e.g., roofs, exterior cladding), and indirectly test entire small buildings with structural loading to simulate wind pressures. In the United States, the test facilities at the FM Global Research Campus includes both direct wind testing of roof components to speeds up to 160 mph, and roof uplift simulation using suction tables per industry standards.

Hurricane simulator

University of Florida’s team led by Forrest Masters developed “the world's most powerful portable hurricane simulator, a giant machine capable of reproducing winds in excess of 120mph (193kph) and recreating rain.” They strapped together 8 industrial sized fans and rigged them up to 4 marine diesel engines, hooked up to a 5,000-gallon (19,000 litre) water tank to keep the engines cooled. The university is currently designing water-resistant windows, wind-proof tiles and altogether stronger structures.

See also

• Emergency preparedness
• Hurricane proof building
• Tropical cyclone
• Wind
• Storm
• Product certification
• Hurricane shutters
• Kinetic energy
• Insurance

External links

• Article from FEMA about Hurricane preparedness
• Article from NOAA about Hurricane preparedness
• Article from HurricaneProtectionGuidance.com about Hurricane preparedness
• Hurricane Mitigation Article
• Hurricane Insurance Information Center
• International Hurricane Protection Association
• International Hurricane Research Center
• Social & Economic Costs of Hurricane & Tropical Storms from "NOAA Socioeconomics" website initiative
• Hurricane Hollow Weather - Atlantic Hurricane Basin News and Information