Salt Lake City ? Despite an economy hammered by recession, sales have doubled every year for a tiny New Hampshire company that makes tents of all things. But these aren’t just any tents. They are for outdoor enthusiasts — not families forced out by foreclosures — and they are definitely not cheap tents.

Nashua-based NEMO Equipment Inc. makes innovative mountaineering tents that stand up on their own without poles, using inflatable air bladders instead for support against the stiffest winds.

The innovative startup with only 13 employees is but one success story in the outdoor gear market that has shown remarkable resilience against economic headwinds.

The more than 4,000 outdoor equipment manufacturers that gathered in Salt Lake City for a trade show last week weren’t just optimistic. Many sounded giddy.

“People are buying tents and sleeping bags, and they’re going camping,” said Kate Ketschek, NEMO’s marketing director. “When times get tough, people get back to their roots.”

The industry was spooked last year when the economy tanked, but it held its own and is rebounding fast. The recession hardly nicked it — sales were down 2 percent in 2009 but are rising at a rate of 6 percent, said Frank Hugelmeyer, president and CEO of the Outdoor Industry Association.

It helps that buyers of nearly $50 billion worth of outdoor gear are, by and large, discriminating, and that many brands like The North Face or Mountain Hardwear have moved into the fashion mainstream.

Many outdoor consumers will spend extra for the best products even if it means cutting back on other purchases, said Joe Mc Swiney, president of Seattle-based Cascade Designs, a diversified manufacturer of camping gear.

“We’re doing fabulously,” said Mc Swiney, who said his private company doesn’t release sales figures but is “experiencing strong growth.”

The optimism was widely shared on the aisles of the Outdoor Retailer show, held twice a year in Salt Lake City. Organizers just signed up to keep it here for several more years.

People are looking to outdoor recreation because it’s cheap, executives said. But there’s money in the business. It supports 6.5 million U.S. jobs. Together with $243 billion in recreational services and money changing hands, the industry has taken to calling itself a $730 billion enterprise — the better to sell politicians on things like the Land and Water Conservation Fund.

The industry regards the Land and Water Conservation fund as its salvation, helping keep people interested in the outdoors. It allocates offshore oil-and-gas royalties for the purchase of land and waterways for public use, with matching grants for states and communities. The big emphasis this year is on creating urban parks, to draw kids away from video games.

The House approved $900 million for the fund on July 30, leaving a final decision with the Senate.

“Our big commitment is getting youth outdoors,” said Steve Rendle, CEO of The North Face, a gorilla of the outdoor industry. “That’s the lifeblood of our industry.”