AEM adds that tariffs on the other 2% of U.S. equipment exports would end in five years. It says the current Colombian tariffs on those products range from 5% to 15%.

Panama, too, has substantial infrastructure work under way, led by the expansion of the Panama Canal, due to be complete in 2014, Lane says. He adds that Panama also is “quadrupling the size of the airport in Panama City” and has road and regional airport projects on tap.

AEM says Panama's tariffs on construction equipment average 6.5%, and range from zero to 10%. But when the new trade agreement is implemented, such equipment immediately will become duty-free.

Although South Korea has the largest economy of the three involved in the new U.S. agreements, the trade deals aren’t expected to have the same direct impact on construction equipment exports as the Colombia and Panama pacts.

Lane explains that South Koreas duties on construction equipment were eliminated in the 1994 Uruguay round of the General Agreement on Tariffs and Trade.