“Our products have recently begun receiving increasing recognition as a green technology, due to their ability to displace the number of disposable gas canisters.”

It’s a hand-held device now patented worldwide that makes a piercing noise audible a mile away. If you’ve been near a construction site with blasting going on, you’ve heard the signals — a series of short toots, then a long “all clear” after the detonation. People buy them for sports events, too. The noise comes from a canister air horn, a disposable item like an aerosol can with compressed freon refrigerant gas that blasting firms and contractors buy in caseloads.

Saanich inventor Dave Woods has sold hundreds to blasting and construction companies and now he is starting to make noise in the market with his own device. He has built and sold 500 of what he calls the Woodscan. A battery-powered compressor powers an airhorn sourced from an auto parts supplier. “It’s starting to blossom right now. It’s starting to take off,” says Woods, who still puts together each Woodscan himself.

In July 2008, Scott Johnson joined Woodscan Industries Inc. as CEO and has experience in early-stage startups. It’s now a “virtual company” with other specialists — an industrial designer who is working out electronics and manufacturing issues and, as chief financial officer, a former vice-president of finance at Aspreva, Victoria’s biggest tech-sector success.

Virtual doesn’t mean invisible. Orders come for dozens of Woodscan airhorns at a time, in construction, blasting, and quarrying. It’s been sold to companies in Finland, North Carolina, and Kentucky and was used on the Sea to Sky Highway project.

A Woodscan costs $500, compared to $20 to $30 apiece for the conventional horns, but the payback is fast, as even small firms spend $2,000 a year on the conventional air canisters, big ones tens of thousands. Woodscan’s batteries can be recharged a hundred-plus times and, each time, you’ll get about 700 toots instead of 30 from a canister. Advanced batteries for the next generation Woodscan, expected to be out by mid-year, should last for a decade, says Woods. It will also have microchip technology.

There are numerous applications beyond blasting, and so far there’s a list of dozens. For example, it could signal unsafe levels of toxic gases in a mine, at oil and gas wells, or in enclosed spaces that require periodic inspection.

The device is durable too. Woods says a big Komatsu tracked excavator digging rock ran over one but it popped out of the crushed rock and kept tooting. Says Johnson: “It’s fairly simple. Sometimes simple gets overlooked.”