Adding to a growing list of accolades, Tesla Motors' Model S has secured the title of safest car on the road.
In its first model year, the premium electric sport sedan is one of just seven cars since 2011 — among hundreds — to receive a five-star rating in each of three federal crash-test categories and overall.
Administered by the National Highway Traffic Safety Administration, the tests also give a separate combined safety score, on which the Model S ranked better than any other U.S. vehicle, according to Clarence Ditlow, director of the Center for Auto Safety, an independent advocacy organization.
"Tesla has thrown down the challenge to the industry as a whole. We are a new company and we beat everybody," Ditlow said. "All the other automakers need to accept Tesla's challenge and do as well or better as Tesla in NHTSA's crash test ratings."
The NHTSA did not respond calls seeking comment.
The Palo Alto automaker trumpeted the results, the latest in a string of critical victories that most notably includes a tie for the highest overall rating ever given out by Consumer Reports, the trusted product-testing magazine. In May, the magazine gave the Tesla a score of 99 out of 100, a high reached previously only by the Lexus LS.
"The Model S set a new record for the lowest likelihood of injury to occupants," the Palo Alto automaker said in a statement.
Investors reacted by pushing Tesla's stock up $4.68, or 3%, to $146.58 in Tuesday's trading. Year to date, the stock is up almost 310%.
Federal regulators measure the severity of injuries that occupants of a vehicle would receive in a rollover, side and frontal crashes. The agency awards star ratings for each of those tests and an overall rating. In each case, five stars is the highest rating, one is the lowest.
Other vehicles also got five-star overall ratings, including the 2014 Chevrolet Silverado 1500, GMC Sierra and Sierra Denali 1500 — the first pickups to do so. But the trucks only received four stars on the rollover tests.
The NHTSA test data also provide a combined vehicle safety score that's not typically released to the public. The lower the score, the better, said Ditlow, who analyzed the ratings data for the Los Angeles Times. The Model S scored lower than any other car, he said, posted a .42. The next best vehicle was the Chevrolet Camaro, at .47.
"There are individual tests where another car has done better than a Tesla," Ditlow said. "But if you combine all the separate tests into one score, then the Tesla does have the best score."
The results also show just how hard it is to win the top rankings.
Honda, for example, has a goal of achieving five star ratings, but only the two-door model its 2013 Accord met that standard, Ditlow said.
By designing its car from scratch, it was probably easier for Tesla to get the top scores, he said. But that fact that so few cars get the top rating indicates that automakers need to commit more money and staff to safety improvements, Ditlow said.
"If you want to engineer a safer vehicle, you can do it," Ditlow said. "The other automakers have decided to spread their engineering talent over other areas."
Tesla said the car's electric drive train - the lack of a gasoline engine - creates a safer design.
The car has "a much longer crumple zone to absorb a high-speed impact," Tesla's statement said. "This is fundamentally a force-over-distance problem -- the longer the crumple zone, the more time there is to slow down occupants at g loads that do not cause injuries."
The architecture of an electric car also helped in the rollover test, the company said. Tesla tucks its large and heavy battery pack below the floor of the car, a factor that adds stability and also improves handling, it said.
Co-founded by tech entrepreneur Elon Musk, Tesla is attempting to become the first successful U.S. automotive startup in nearly a century. It started selling the Model S about a year ago.
The price starts at $63,570 and climbs to more than $100,000 if a customer springs for a larger battery, which extends the vehicle's range to over 200 miles on one charge, more than double most electric cars. The Model S has received a strong reception from the automotive press.
"Slipping behind the wheel of the Tesla Model S is like crossing into a promising zero-emissions future," Consumer Reports said in its review.
The car is "brimming with innovation, delivers world-class performance and is interwoven throughout with impressive attention to detail. It's what Marty McFly might have brought back in place of his DeLorean in 'Back to the Future,' " the magazine said.
The top safety rating further adds to Tesla's reputation as a legitimate contender, said Alec Gutierrez, senior analyst at Kelley Blue Book.
"This paves the way for Tesla to gain more acceptance among mainstream buyers in the years to come," he said, "provided that they are able to maintain the features, style and driving dynamics of the Model S in a more affordable package."
Already, brisk sales of the Model S helped Tesla earn its first profit, an $11.2-million gain, in the first quarter of this year. Tesla expects to sell about 20,000 — every car it can turn out — of the sport sedans this year.
Tesla's finances also are being helped by special California and other environmental credits it collects every time it sells a Model S. It has sold about $150 million of such credits to other automakers so far this year.
It builds the car at a factory in Fremont, Calif., where it also plans to make the Model X — an electric SUV built on the same platform as the Model S and sharing much of its technology — starting next year.