WASHINGTON — Unlike most cars on the road, the pint-sized 2008 Smart fortwo evokes a simple question at first glance: "How safe is it?"

The micro car, the smallest car for sale in the U.S. market, offers a good level of safety, according to new crash tests conducted by the insurance industry.

The 8-foot, 8-inch vehicle received the highest rating of good in front-end and side-impact testing by the Insurance Institute for Highway Safety, helping address some concerns that consumers may be more vulnerable in the tiny two-seater.

The tests, released today, show how well vehicles stack up against others of similar size and weight. The institute noted that the front-end test scores can't be compared across weight classes, meaning a small car that earns a good rating isn't considered safer than a large car that did not earn the highest rating.

Adrian Lund, the institute's president, said a small car may be more practical in congested urban areas where serious, high-speed crashes are less likely. The institute conducted the crash test to help guide consumers who want a small car that can give them good protection.

"All things being equal in safety, bigger and heavier is always better. But among the smallest cars, the engineers of the Smart did their homework and designed a high level of safety into a very small package," Lund said.

The institute's frontal crash test simulates a 40-mph crash with a similar vehicle. The side crash simulates what would happen if the vehicle was struck in the side by a sport utility vehicle at 31 mph.

In a test that assessed the vehicle's protection in rear crashes, the fortwo received the second-highest rating of acceptable.

Smart, a division of Daimler AG's Mercedes-Benz brand, has arrived in U.S. showrooms this year as consumers deal with rising fuel prices. The automaker has received more than 30,000 reservations for the vehicle — which has a base price of more than $12,000 with destination charges included and more than $17,000 for a fully loaded Smart passion convertible. Customers are putting down $99 to reserve a car.

The vehicle, which had sold 6,159 units through the end of April, gets 33 miles per gallon in the city and 41 mpg on the highway. The fortwo is more than 3 feet shorter and nearly 700 pounds lighter than a Mini Cooper.

In earlier crash tests conducted by the government, Smart received the top score of five stars in side testing but the driver door unlatched during the test and opened. While it did not affect the vehicle's test score, government regulators said the incident required them to note a safety concern for the vehicle which will appear on window stickers at dealerships.

The concern was warranted because the unlatching of the door could increase the likelihood of a driver or passenger being ejected from the vehicle, the National Highway Traffic Safety Administration said.

When the IIHS conducted its side test, the driver door also became unlatched. But the institute said the injury measurements on the test dummy were low and the opening didn't affect the dummy's movement.

The 1,800-pound car has a steel safety cage and four standard air bags, including two in front and two on the sides to protect the head and abdomen. It also has standard electronic stability control, which is designed to stop vehicles from swerving off the road.

"America has never seen a car this size before and their first question usually isn't about (fuel) economy, it's about safety," said Dave Schembri, president of Smart USA. "And that's why we think these results are so very important."