The Transportation Security Administration has finished testing the device at Miami International Airport and Newark Liberty International Airport. Testing is ongoing in Los Angeles, Detroit and Las Vegas, agency spokesman Nico Melendez said Tuesday.
Testing was to begin in Boston on Wednesday.
TSA expects to deploy about 200 of the devices at a number of airports around the country by October, Melendez said.
The technology, which detects explosive material in sealed bottles of liquid, only is used on passengers selected for secondary inspections before boarding.
The device adds another layer of security to government restrictions on carry-on liquids instituted in September following revelations in August about an alleged terrorist plot.
Authorities say Britain-based terrorists were planning to construct bombs onboard aircraft from small amounts of liquids or gels carried in innocent-looking containers.
Under the government's "3-1-1 rule," passengers have been allowed to carry on bottles of liquid of three ounces or less. The liquid must be stored in a quart-size, clear, zip-top plastic bag, with no more than one plastic bag for each passenger.
The scanning device, made by Washington-based ICx Technologies, has been previously employed by the U.S. government for other uses.