Tesla tested Model X's bioweapon defense mode, and it performed admirably.

One of the most surprising features of Tesla's crazy-expensive, crazy-fast electric SUV, the Model X, was its bioweapon defense mode — an air filter so powerful it can save you from a biological attack.

On Monday, Tesla published a blog post detailing a test the company had performed to show how well the bioweapon defense mode works in extreme conditions.

The test was simple: a Model X was placed in a sealed plastic bubble, which was contaminated with what Tesla calls extreme levels of pollution or 1,000 µg/m3 of PM2.5. That's a very large concentration of tiny particles, 2.5 micrometers in diameter, which are particularly dangerous for human health. For comparison, WHO lists average annual PM2.5 levels at 16 µg/m3 in London and 56 µg/m3 in Beijing.

The doors of the Model X were then closed, and the air filtration system, which Tesla says is HEPA-certified, was turned on. The results are shown in the graph below — within a couple of minutes, the system improved the air quality to a level where pollution was undetectable. The system also improves the quality of the air outside the car somewhat. 

"Bioweapon Defense Mode is not a marketing statement, it is real. You can literally survive a military grade bio attack by sitting in your car," Tesla says in the post. 

Of course, the entire test was performed by Tesla, so we'll reserve judgement until a third party performs a similar test. But it's comforting to know that, if you're rich enough to own a Tesla Model X (and soon, the Model S, which will be getting the bioweapon defense mode as well), even very high levels of pollution won't harm you.