As a high terror warning illuminates America's fears and the possibility of war looms, survival gear is once again a hot commodity.

Government advisories to prepare for terrorist attacks have many stocking up on a cornucopia of supplies from gas masks to biohazard suits, but experts say for the most part, safety can't be bought.

"Save your money," advised Larry Johnson, a former State Department counter-terrorism official. "The federal government really does have good capabilities."

Whether you're looking to escape from a high-rise building or prevent inhalation of deadly gases, there are products out there for the panicked or just plain cautions. And those hawking the gear say it's better to be safe than sorry.

"It's smart to be prepared," said Holly Whiting, president of Survivalgeardirect.com, adding that the site's traffic and sales have been up recently. The site sells an emergency mask that the company claims is 95 percent efficient in filtering out anthrax, small pox and sarin using an activated carbon filter.

"When the government puts out an alert you should wear it all the time," said Whiting. "It's a lot better than a regular gas mask because if a gas mask isn't custom fitted to your face there's a possibility it will leak."

However, Johnson is skeptical of safety products. Purchasing such gear may allay people's nerves, but it won't save your life, he said.

"The reality is, if a terror group uses a biological weapon, people won't know about it until they start feeling sick … most agents are colorless and odorless," he said. "A terrorist group won't announce, 'Attention, we will launch an attack in five minutes, please put on your gas masks now!'"

The proliferation of online survival gear shops, popping up as fears rise, disgusts Johnson, who calls these companies "terrorist profiteers."

"The fear mongering that is going on right now is so irresponsible," he said.

Captain Dave's Survival Shop, an online retailer, is having a "special pre-invasion sale."

"Worried about the war with Iraq? Terrorist attacks? Stock up here," the homepage beckons. Some of the site's best-selling items include a civil defense radiation meter, an Israeli gas mask for children and MREs (Meals Ready to Eat).

"These people are taking advantage of legitimate concerns of Americans and playing on those fears to profit," said Johnson. "Most of what they are selling will not be useful if there is a terror attack."

Nevertheless the shelves are being cleaned online and at retail outlets such as Safer America in New York City, where owner Fred Samama said it's been crazy with consumers.

"We've sold out on a lot of items, people are queuing just to get into the store," said Samama. "Online sales have been crazy. There's a new order placed every two minutes."

For the most part, shoppers have been disciplined and calm, said Samama. However, he added, "Some call us words because we don't have things in stock, but we are taking it well because we understand they are nervous."

Another company has created an invention that may help people escape high-rise buildings. The Advanced Modular Evacuation System resembles a long chute through which people could slide to escape from buildings up to 23 floors high.

But no matter the purchasing or planning, Johnson is blunt in assessing the effectiveness of such products in an emergency.

"If you happen to be in wrong place at wrong time, even if you've got a gas mask it won't help," said Johnson, adding that masks could be ill-fitted allowing leaks, trap inhalants in or even suffocate the wearer.

"The best security product you could buy is a nice pair of running shoes."