Shoppers have scurried to hardware stores to stockpile plastic sheeting and duct tape in preparation for possible terrorist attacks.
This portable, inflatable safe room is sold by Maryland-based REHCC. It's designed to block out biological or chemical agents in case of a terrorist attack.
Potential Terrorist Threats: A Primer
Biological agents are organisms or toxins that can kill or incapacitate people, livestock and crops. The three basic types likely to be weaponized are bacteria, viruses and toxins.
Chemical warfare agents are poisonous vapors, aerosols, liquids or solids with toxic effects on people, animals or plants. They can be released by bombs, sprayed from aircraft, boats or vehicles, or used as a liquid.
Dirty bombs, also known as radiological dispersion devices (RDDs), combine conventional explosives with radioactive material. Designed to scatter dangerous and sub-lethal amounts of radioactive material over a general area, dirty bombs require much less technical know-how than nuclear devices.
Source: U.S. Department of Homeland Security
Many Americans have spent the past few days preparing to combat terrorism with duct tape and plastic sheeting. On Monday, the White House suggested people purchase such supplies to seal up doors and windows in the event of an attack using a chemical or biological weapon. That government warning set off a race to hardware stores and home improvement centers but left bio-terrorism experts puzzled. As NPR's Jon Hamilton reports, many experts say most people don't need an airtight room, and those who do will probably want something safer than duct tape and plastic.
According to Randy Larsen, director of the Anser Institute for Homeland Security, duct tape, plastic sheeting and other "safe room" supplies are largely ineffectual. He says the public should focus on more important preparations, such as having a plan to reach every family member at any hour in case of emergency. Families, he adds, also need to ask questions about transportation and logistics.
"Who is going to pick up the kids from nursery school if you can't get there?" Larsen said. "Who is going to take care of your pets if you can't get home for three days? You better be coordinating that with your neighbors and relatives."
Once those issues are taken care of, Larsen says, people should put together a disaster-supply kit like the one suggested by the American Red Cross, which includes items such as sleeping bags, extra clothing, a battery-powered radio and any necessary prescription drugs.
Larsen says these issues need to be handled before consumers start thinking about creating an airtight space to seal out chemical or biological agents. But according to Cliff Enz of the Regional Environmental Hazard Containment Corporation (REHCC) in Landover, Md., creating that airtight space poses another problem.
"Duct-taping your windows and putting plastic sheeting over everything is only secure as long as your air supply lasts," Enz notes. "When your air supply goes, so do you."
REHCC sells a suitcase-sized system that turns into an airtight tent equipped with a special air pump that filters out particulate matter. Enz says it's the same one owned by more than a million families in Israel, where consumers have spent years preparing for biological and chemical attacks.
However, such safe-room systems cost upwards of $3,000 each, and Enz says their usefulness is questionable even in high-risk areas such as New York or Washington, D.C.