QUESTION: Is Hawaii the only state with safety inspections? I've driven through 41 states and never saw safety inspections there.

ANSWER: Hawaii is not the only state, but it is in the minority.

The state Department of Transportation did not have an official list of states that require cars to pass annual safety inspections, but we found information about inspection practices in the United States and elsewhere on Wikipedia, the online encyclopedia.

According to that source, 18 states have an annual or biannual safety inspection program, some requiring emissions testing as well, while Alabama and Maryland require safety inspections only prior to a sale or transfer of ownership.

In addition to Hawaii, the states requiring some kind of periodic safety inspection are Delaware, Louisiana, Maine, Massachusetts, Mississippi, Missouri, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, Texas, Utah, Vermont, Virginia and West Virginia.

Nebraska requires a safety inspection only if a vehicle is brought in from another state.

Meanwhile, the Clean Air Act requires states with metropolitan areas that do not meet federal clean air standards to have vehicle emission inspection programs. Those inspection programs may only be for a certain area or county in a state.

States that do have emissions inspections in at least some jurisdictions are Arizona, California, Colorado, Connecticut, Georgia, Illinois, Indiana, New Mexico, Nevada, Ohio, Oregon, Tennessee, Washington and Wisconsin.

States with neither a safety nor emissions inspection program are Alaska, Arkansas, Florida, Idaho, Iowa, Kansas, Kentucky, Michigan, Minnesota, Montana, North Dakota, Oklahoma, South Carolina, South Dakota and Wyoming.

Critics say safety inspections are costly and ineffective, but bills that periodically are introduced to eliminate the requirement have never made it out of the state Legislature.

QUESTION: I have seen a few cars driving on Oahu with the safety check decal applied onto the middle of the rear mounted license plate. Is this legal?

ANSWER: Sticking safety inspection decals on the license plate is not illegal—unless they obscure the license plate.

But that practice is not encouraged, and vehicle owners are told to affix the stickers to the right rear bumper.

In a previous column city Motor Vehicle and Licensing Division Administrator Dennis Kamimura pointed to Section 19-133.2-24(b) of the state Department of Transportation Administrative Rules regarding safety stickers.

That section says that safety decals “;placed on or next to the license plate 'may' be a violation if it is considered by law enforcement personnel as obscuring the license plate since safety inspection decals are not authorized to be placed on the license plate, or not in vicinity of the right rear bumper.”;

So it depends on how the sticker is placed on the license plate.

Meanwhile, it is not illegal either to place the safety decals on metal holders.

However, Kamimura told us the intent of the administrative rule is to have standardized placement of the decals on the right rear bumper, where police can clearly view the decal within 50 feet.