SAN FRANCISCO — The president of Building Protection Systems talks about the scenario as if it were the description of a scene from the television show "24."

A terrorist wheels up canisters filled with deadly gases to a buildings ventilation system. He turns the nozzle and walks away. Minutes later, everybody is dead.

But to Greg Eiler, founder of this San Francisco-based company, this is neither Hollywood nor a joke.

"It would be easy to do," Eiler said. "So really it's not a matter of if, but a matter of when it might happen."

Some industries, such as semiconductor and jewelry, have access to some of these deadly chemicals making the potential threat more serious, Eiler said.

And this is the reason the company, known as BPSI, was created. The startup company has designed a system that utilizes a sensor that can detect when one of 38 potentially deadly chemicals are exposed to it. Within seconds, an entire ventilation system can be blocked off and lives saved, Eiler said.

The biggest plus for BPSI is that it has the endorsement and senior advisory of Tom Ridge, the first U.S. Secretary of Homeland Security and former governor of Pennsylvania.

"Forever more, in a post-911 world, weapons of mass effect like chemical should be on our minds forever more," Ridge said. "What we're going to do with BPSI is introduce them to companies that I think would have a responsibility or liability out there to protect some of these major public and private buildings out there."

There has never been an intentional targeted terrorist attack of this kind in the U.S.

There are other companies that make sensors on the market, but many of them have a problem with false positives. For example, if non-toxic molecules of ammonia from a window washer gets into the ventilation system, it would be a huge problem if the sensors are triggers.

"It has to run perfectly, because if entire buildings are evacuated from a false positive, by the second or third time it will be unplugged," Eiler said.

The company has done at least 65,000 runs on the system and has never had one, Eiler said.

Opponents to their solution come in "three buckets," Eiler says. Ones that have no idea of the seriousness of chemical or radiological threats, and those that feel there's nothing out there that can address it are the easiest to sway belief.

"The hardest ones are those that no matter how important they realize it to be, they're not interested because of the costs to the bottom line," Eiler said.

From signed contract to installation, the process of putting the necessary equipment in a building generally takes about 8 weeks. The equipment costs about 40 cents to a dollar per square foot. A site such as the Transamerica Pyramid in San Francisco might cost about $500,000, Eiler estimates.

Not only does BPSI's system block the ventilation system, but it notifies law enforcement of the threat and the precise chemicals so they're prepared upon arrival.

Not only for protection against security threats, the system can also be used to protect against accidental threats. For example, if a building is near a chemical plant, it can be set up to secure the building if levels rise to dangerous levels.

Ridge says he believes President Barack Obama currently doesn't know about BPSI, and that the company will not lobby the government.

The company was initially incorporated in 2005, but officially launched last May with its first installation in the Prudential World Headquarters Building in Newark, N.J.

It was initially funded through money from friends and families, and now through angel investors. It's total funding thus far is about $3 million. It conducts its research and development in Concord at Detroit Avenue near Costco.

In a perfect world, both the company and Ridge would love to see a system such as this to one day be required in building code such just as fire sprinklers are. But for now, they just hope there "true thought leaders" that will see the importance of it now.

"The only time people feel security has value is when they don't have it," Ridge said. "In time I think people will think of security in the process of building.